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Szczepanska-Sadowska E. Interplay of Angiotensin Peptides, Vasopressin, and Insulin in the Heart: Experimental and Clinical Evidence of Altered Interactions in Obesity and Diabetes Mellitus. Int J Mol Sci 2024; 25:1310. [PMID: 38279313 PMCID: PMC10816525 DOI: 10.3390/ijms25021310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/18/2024] [Accepted: 01/18/2024] [Indexed: 01/28/2024] Open
Abstract
The present review draws attention to the specific role of angiotensin peptides [angiotensin II (Ang II), angiotensin-(1-7) (Ang-(1-7)], vasopressin (AVP), and insulin in the regulation of the coronary blood flow and cardiac contractions. The interactions of angiotensin peptides, AVP, and insulin in the heart and in the brain are also discussed. The intracardiac production and the supply of angiotensin peptides and AVP from the systemic circulation enable their easy access to the coronary vessels and the cardiomyocytes. Coronary vessels and cardiomyocytes are furnished with AT1 receptors, AT2 receptors, Ang (1-7) receptors, vasopressin V1 receptors, and insulin receptor substrates. The presence of some of these molecules in the same cells creates good conditions for their interaction at the signaling level. The broad spectrum of actions allows for the engagement of angiotensin peptides, AVP, and insulin in the regulation of the most vital cardiac processes, including (1) cardiac tissue oxygenation, energy production, and metabolism; (2) the generation of the other cardiovascular compounds, such as nitric oxide, bradykinin (Bk), and endothelin; and (3) the regulation of cardiac work by the autonomic nervous system and the cardiovascular neurons of the brain. Multiple experimental studies and clinical observations show that the interactions of Ang II, Ang(1-7), AVP, and insulin in the heart and in the brain are markedly altered during heart failure, hypertension, obesity, and diabetes mellitus, especially when these diseases coexist. A survey of the literature presented in the review provides evidence for the belief that very individualized treatment, including interactions of angiotensins and vasopressin with insulin, should be applied in patients suffering from both the cardiovascular and metabolic diseases.
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Affiliation(s)
- Ewa Szczepanska-Sadowska
- Department of Experimental and Clinical Physiology, Laboratory of Centre for Preclinical Research, Medical University of Warsaw, 02-097 Warsaw, Poland
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2
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Provitera L, Amelio GS, Tripodi M, Raffaeli G, Macchini F, Amodeo I, Gulden S, Cortesi V, Manzoni F, Cervellini G, Tomaselli A, Zuanetti G, Lonati C, Battistin M, Kamel S, Parente V, Pravatà V, Villa S, Villamor E, Mosca F, Cavallaro G. Veno-Arterial Extracorporeal Membrane Oxygenation (ECMO) Impairs Bradykinin-Induced Relaxation in Neonatal Porcine Coronary Arteries. Biomedicines 2022; 10:biomedicines10092083. [PMID: 36140183 PMCID: PMC9495700 DOI: 10.3390/biomedicines10092083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/18/2022] [Accepted: 08/19/2022] [Indexed: 11/26/2022] Open
Abstract
Extracorporeal membrane oxygenation (ECMO) is a lifesaving support for respiratory and cardiovascular failure. However, ECMO induces a systemic inflammatory response syndrome that can lead to various complications, including endothelial dysfunction in the cerebral circulation. We aimed to investigate whether ECMO-associated endothelial dysfunction also affected coronary circulation. Ten-day-old piglets were randomized to undergo either 8 h of veno-arterial ECMO (n = 5) or no treatment (Control, n = 5). Hearts were harvested and coronary arteries were dissected and mounted as 3 mm rings in organ baths for isometric force measurement. Following precontraction with the thromboxane prostanoid (TP) receptor agonist U46619, concentration−response curves to the endothelium-dependent vasodilator bradykinin (BK) and the nitric oxide (NO) donor (endothelium-independent vasodilator) sodium nitroprusside (SNP) were performed. Relaxation to BK was studied in the absence or presence of the NO synthase inhibitor Nω-nitro-L-arginine methyl ester HCl (L-NAME). U46619-induced contraction and SNP-induced relaxation were similar in control and ECMO coronary arteries. However, BK-induced relaxation was significantly impaired in the ECMO group (30.4 ± 2.2% vs. 59.2 ± 2.1%; p < 0.0001). When L-NAME was present, no differences in BK-mediated relaxation were observed between the control and ECMO groups. Taken together, our data suggest that ECMO exposure impairs endothelium-derived NO-mediated coronary relaxation. However, there is a NO-independent component in BK-induced relaxation that remains unaffected by ECMO. In addition, the smooth muscle cell response to exogenous NO is not altered by ECMO exposure.
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Affiliation(s)
- Livia Provitera
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Giacomo S. Amelio
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Matteo Tripodi
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Genny Raffaeli
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milan, Italy
- Correspondence:
| | - Francesco Macchini
- Department of Pediatric Surgery, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Pediatric Surgery, ASST Grande Ospedale Metropolitano (GOM) Niguarda, 20162 Milan, Italy
| | - Ilaria Amodeo
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Silvia Gulden
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Valeria Cortesi
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milan, Italy
| | - Francesca Manzoni
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milan, Italy
| | - Gaia Cervellini
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milan, Italy
| | - Andrea Tomaselli
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milan, Italy
| | - Gabriele Zuanetti
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy
| | - Caterina Lonati
- Center for Preclinical Investigation, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Michele Battistin
- Center for Preclinical Investigation, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Shady Kamel
- Betamed Perfusion Service, 00192 Rome, Italy
| | | | - Valentina Pravatà
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Stefania Villa
- Transfusion Center and Blood Component Bank of Rare Groups, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Eduardo Villamor
- Department of Pediatrics, Maastricht University Medical Center (MUMC+), School for Oncology and Reproduction (GROW), University of Maastricht, 6229 Maastricht, The Netherlands
| | - Fabio Mosca
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milan, Italy
| | - Giacomo Cavallaro
- Neonatal Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
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3
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Liu T, Schroeder H, Power GG, Blood AB. A physiologically relevant role for NO stored in vascular smooth muscle cells: A novel theory of vascular NO signaling. Redox Biol 2022; 53:102327. [PMID: 35605454 PMCID: PMC9126848 DOI: 10.1016/j.redox.2022.102327] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 04/16/2022] [Accepted: 04/29/2022] [Indexed: 01/16/2023] Open
Abstract
S-nitrosothiols (SNO), dinitrosyl iron complexes (DNIC), and nitroglycerine (NTG) dilate vessels via activation of soluble guanylyl cyclase (sGC) in vascular smooth muscle cells. Although these compounds are often considered to be nitric oxide (NO) donors, attempts to ascribe their vasodilatory activity to NO-donating properties have failed. Even more puzzling, many of these compounds have vasodilatory potency comparable to or even greater than that of NO itself, despite low membrane permeability. This raises the question: How do these NO adducts activate cytosolic sGC when their NO moiety is still outside the cell? In this review, we classify these compounds as ‘nitrodilators’, defined by their potent NO-mimetic vasoactivities despite not releasing requisite amounts of free NO. We propose that nitrodilators activate sGC via a preformed nitrodilator-activated NO store (NANOS) found within the vascular smooth muscle cell. We reinterpret vascular NO handling in the framework of this NANOS paradigm, and describe the knowledge gaps and perspectives of this novel model.
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4
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Seckler JM, Shen J, Lewis THJ, Abdulameer MA, Zaman K, Palmer LA, Bates JN, Jenkins MW, Lewis SJ. NADPH diaphorase detects S-nitrosylated proteins in aldehyde-treated biological tissues. Sci Rep 2020; 10:21088. [PMID: 33273578 PMCID: PMC7713249 DOI: 10.1038/s41598-020-78107-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/19/2020] [Indexed: 11/25/2022] Open
Abstract
NADPH diaphorase is used as a histochemical marker of nitric oxide synthase (NOS) in aldehyde-treated tissues. It is thought that the catalytic activity of NOS promotes NADPH-dependent reduction of nitro-blue tetrazolium (NBT) to diformazan. However, it has been argued that a proteinaceous factor other than NOS is responsible for producing diformazan in aldehyde-treated tissues. We propose this is a NO-containing factor such as an S-nitrosothiol and/or a dinitrosyl-iron (II) cysteine complex or nitrosated proteins including NOS. We now report that (1) S-nitrosothiols covalently modify both NBT and TNBT, but only change the reduction potential of NBT after modification, (2) addition of S-nitrosothiols or β- or α-NADPH to solutions of NBT did not elicit diformazan, (3) addition of S-nitrosothiols to solutions of NBT plus β- or α-NADPH elicited rapid formation of diformazan in the absence or presence of paraformaldehyde, (4) addition of S-nitrosothiols to solutions of NBT plus β- or α-NADP did not produce diformazan, (5) S-nitrosothiols did not promote NADPH-dependent reduction of tetra-nitro-blue tetrazolium (TNBT) in which all four phenolic rings are nitrated, (6) cytoplasmic vesicles in vascular endothelial cells known to stain for NADPH diaphorase were rich in S-nitrosothiols, and (7) procedures that accelerate decomposition of S-nitrosothiols, markedly reduced NADPH diaphorase staining in tissue sections subsequently subjected to paraformaldehyde fixation. Our results suggest that NADPH diaphorase in aldehyde-fixed tissues is not enzymatic but is due to the presence of NO-containing factors (free SNOs or nitrosated proteins such as NOS), which promote NADPH-dependent reduction of NBT to diformazan.
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Affiliation(s)
- James M Seckler
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Jinshan Shen
- Department of Pharmacology, University of Iowa, Iowa City, IA, 52242, USA
| | - Tristan H J Lewis
- Department of Pharmacology and Physiology, University of Georgia, Athens, GA, 30602, USA
| | - Mohammed A Abdulameer
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Khalequz Zaman
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Lisa A Palmer
- Department of Pediatrics, University of Virginia, Charlottesville, VA, 801366, USA
| | - James N Bates
- Department of Anesthesia, University of Iowa, Iowa City, IA, 52242, USA
| | - Michael W Jenkins
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, 44106, USA.,Department of Bioengineering, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Stephen J Lewis
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, 44106, USA. .,Department of Pharmacology, Case Western Reserve University, Cleveland, OH, 44106, USA.
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5
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Emami B, Shakeri F, Gholamnezhad Z, Saadat S, Boskabady M, Azmounfar V, Sadatfaraji H, Boskabady MH. Calcium and potassium channels are involved in curcumin relaxant effect on tracheal smooth muscles. PHARMACEUTICAL BIOLOGY 2020; 58:257-264. [PMID: 32208946 PMCID: PMC7170316 DOI: 10.1080/13880209.2020.1723647] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Context: Curcumin, the active component of Curcuma longa L. (Zingiberaceae), exhibits a wide variety of biological activities including vasodilation and anti-inflammation.Objective: The relaxant effect of curcumin in tracheal smooth muscle (TSM) was not examined so far, thus, this study was designed to assess the relaxant effect of curcumin on rat TSM and examine the underlying mechanism(s) responsible for this effect.Materials and methods: TSM was contracted by KCl (60 mM) or methacholine (10 μM), and cumulative concentrations of curcumin (12.5, 25, 50, and 100 mg/mL) or theophylline (0.2, 0.4, 0.6, and 0.8 mM, as positive control) were added to organ bath. The relaxant effect of curcumin was examined in non-incubated or incubated tissues with atropine (1 μM), chlorpheniramine (1 μM), indomethacin (1 μM), and papaverine (100 μM).Results: In non-incubated TSM, curcumin showed significant relaxant effects on KCl-induced contraction in a concentration-dependent manner (p < 0.001 for all concentrations). The relaxant effects of curcumin 12.5, 25, and 50 mg/mL were significantly lower in atropine-incubated tissue compared to non-incubated TSM (p < 0.05 to p < 0.001). A significant difference was observed in EC50 between atropine-incubated (48.10 ± 2.55) and non-incubated (41.65 ± 1.81) tissues (p < 0.05). Theophylline showed a significant relaxant effect on both KCl and methacholine-induced contraction in a concentration-dependent manner (p < 0.001 for all cases).Conclusions: The results indicated a relatively potent relaxant effect of curcumin on TSM, which was less marked than the effect of theophylline. Calcium channel blocking and/or potassium channel opening properties of curcumin may be responsible for TSM relaxation.
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Affiliation(s)
- Bahman Emami
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Farzaneh Shakeri
- Natural Products and Medicinal Plants Research Center, North Khorasan University of Medical Sciences, Bojnurd, Iran
| | - Zahra Gholamnezhad
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Saeideh Saadat
- Department of Physiology, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Marzie Boskabady
- Dental Materials Research Center and Department of Pediatric Dentistry, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Vahab Azmounfar
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hamed Sadatfaraji
- Department of Pharmacognosy, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad Hossein Boskabady
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- CONTACT Mohammad Hossein Boskabady Neurogenic Inflammation Research Center and Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
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6
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Increased Mortality and Vascular Phenotype in a Knock-In Mouse Model of Retinal Vasculopathy With Cerebral Leukoencephalopathy and Systemic Manifestations. Stroke 2020; 51:300-307. [DOI: 10.1161/strokeaha.119.025176] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Background and Purpose—
Retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S) is an autosomal dominant small vessel disease caused by C-terminal frameshift mutations in the
TREX1
gene that encodes the major mammalian 3′ to 5′ DNA exonuclease. RVCL-S is characterized by vasculopathy, especially in densely vascularized organs, progressive retinopathy, cerebral microvascular disease, white matter lesions, and migraine, but the underlying mechanisms are unknown.
Methods—
Homozygous transgenic RVCL-S knock-in mice expressing a truncated Trex1 (three prime repair exonuclease 1) protein (similar to what is seen in patients) and wild-type littermates, of various age groups, were subjected to (1) a survival analysis, (2) in vivo postocclusive reactive hyperemia and ex vivo Mulvany myograph studies to characterize the microvascular and macrovascular reactivity, and (3) experimental stroke after transient middle cerebral artery occlusion with neurological deficit assessment.
Results—
The mutant mice show increased mortality starting at midlife (
P
=0.03 with hazard ratio, 3.14 [95% CI, 1.05–9.39]). The mutants also show a vascular phenotype as evidenced by attenuated postocclusive reactive hyperemia responses (across all age groups; F[1, 65]=5.7,
P
=0.02) and lower acetylcholine-induced relaxations in aortae (in 20- to 24-month-old mice; RVCL-S knock-in: E
max
: 37±8% versus WT: E
max
: 65±6%,
P
=0.01). A vascular phenotype is also suggested by the increased infarct volume seen in 12- to 14-month-old mutant mice at 24 hours after infarct onset (RVCL-S knock-in: 75.4±2.7 mm
3
versus WT: 52.9±5.6 mm
3
,
P
=0.01).
Conclusions—
Homozygous RVCL-S knock-in mice show increased mortality, signs of abnormal vascular function, and increased sensitivity to experimental stroke and can be instrumental to investigate the pathology seen in patients with RVCL-S.
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7
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Emami B, Shakeri F, Ghorani V, Boskabady MH. Relaxant effect of Curcuma longa on rat tracheal smooth muscle and its possible mechanisms. PHARMACEUTICAL BIOLOGY 2017; 55:2248-2258. [PMID: 29169285 PMCID: PMC6130477 DOI: 10.1080/13880209.2017.1400079] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Revised: 06/25/2017] [Accepted: 10/30/2017] [Indexed: 05/22/2023]
Abstract
CONTEXT Turmeric is a spice obtained from the root of Curcuma longa L. (Zingiberaceae) with anti-aging, anticancer, anti-Alzheimer's disease, antioxidant and other medicinal properties. OBJECTIVE The relaxant effect of C. longa on rat tracheal smooth muscle and its possible mechanisms were investigated in this study. MATERIALS AND METHODS The relaxant effects of four cumulative concentrations of hydro-ethanol extract of C. longa (6.25, 12.5, 25, 50 mg/mL) were studied on tracheal smooth muscle precontracted by methacholine or KCl in non-incubated or incubated with different substances including propranolol, diltiazem, L-NAME, glibenclamide, atropine, chlorpheniramine, indomethacin and papaverine. The duration of the study was 84 days. RESULTS In non-incubated tracheal smooth muscle, the extract of C. longa showed significant concentration-dependent relaxant effects (p < 0.001 for all concentrations on both KCl and methacholine-induced contraction). There was no significant difference in the relaxant effects between C. longa and theophylline in both methacholine and KCl-induced contraction conditions. In tissues incubated with propranolol, diltiazem, L-NAME and glibenclamide on methacholine-induced contraction and in tissues incubated with atropine, chlorpheniramine, indomethacin and papaverine on KCl-induced contraction, the extract also showed significant concentration-dependent relaxant effects (p < 0.001). EC50 values of C. longa between non-incubated (16.22 ± 0.62) and incubated tissues (atropine: 13.03 ± 0.55, chlorpheniramine: 12.94 ± 0.68, indomethacin: 14.80 ± 0.57 and papaverine: 16.16 ± 1.42) were not significantly different. CONCLUSIONS Tracheal smooth muscle relaxant effects of C. longa, were comparable to those of theophylline, which could be due to the presence of methylxanthines or its possible interaction with non-adrenergic non-cholinergic nervous system.
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Affiliation(s)
- Bahman Emami
- Neurogenic Inflammation Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Farzaneh Shakeri
- Neurogenic Inflammation Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Vahideh Ghorani
- Neurogenic Inflammation Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad Hossein Boskabady
- Neurogenic Inflammation Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- CONTACT Mohammad Hossein Boskabady , Neurogenic Inflammation Research Center and Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad9177948564, Iran
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8
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Kıroğlu OE, Özü ÖY, Emre M, Bayel İ, Kumcu EK, Seçilmiş MA. Residual NO modulates contractile responses and membrane potential in isolated rat mesenteric arteries. Nitric Oxide 2017; 71:21-26. [DOI: 10.1016/j.niox.2017.10.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/28/2017] [Accepted: 10/11/2017] [Indexed: 12/17/2022]
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9
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Edward JA, Pankey EA, Jupiter RC, Lasker GF, Yoo D, Reddy VG, Peak TC, Chong I, Jones MR, Feintech SV, Lindsey SH, Kadowitz PJ. Analysis of erectile responses to bradykinin in the anesthetized rat. Am J Physiol Heart Circ Physiol 2015; 309:H499-511. [PMID: 26055796 DOI: 10.1152/ajpheart.00765.2014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 05/28/2015] [Indexed: 12/31/2022]
Abstract
The kallikrein-kinin system is expressed in the corpus cavernosa, and bradykinin (BK) relaxes isolated corpora cavernosal strips. However, erectile responses to BK in the rat have not been investigated in vivo. In the present study, responses to intracorporal (ic) injections of BK were investigated in the anesthetized rat. BK, in doses of 1-100 μg/kg ic, produced dose-related increases in intracavernosal pressure (ICP) and dose-related deceases in mean arterial pressure (MAP). When decreases in MAP were prevented by intravenous injections of angiotensin II (Ang II), increases in ICP, in response to BK, were enhanced. Increases in ICP, ICP/MAP ratio, and area under the curve and decreases in MAP in response to BK were inhibited by the kinin B2 receptor antagonist HOE-140 and enhanced by the angiotensin-converting enzyme (ACE) inhibitor captopril and by Ang-(1-7). Increases in ICP, in response to BK, were not attenuated by the nitric oxide (NO) synthase inhibitor (N(ω)-nitro-L-arginine methyl ester) or the soluble guanylate cyclase inhibitor (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one) but were attenuated by the cyclooxygenase inhibitor, sodium meclofenamate. Decreases in MAP were not attenuated by either inhibitor. These data suggest that erectile responses are mediated by kinin B2 receptors and modulated by decreases in MAP. These data indicate that ACE is important in the inactivation of BK and that erectile and hypotensive responses are independent of NO in the penis or the systemic vascular bed. Erectile responses to cavernosal nerve stimulation are not altered by BK or HOE-140, suggesting that BK and B2 receptors do not modulate nerve-mediated erectile responses under physiologic conditions. These data suggest that erectile responses to BK are mediated, in part, by the release of cyclooxygenase products.
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Affiliation(s)
- Justin A Edward
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Edward A Pankey
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Ryan C Jupiter
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - George F Lasker
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Daniel Yoo
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Vishwaradh G Reddy
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Taylor C Peak
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Insun Chong
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Mark R Jones
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Samuel V Feintech
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Sarah H Lindsey
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Philip J Kadowitz
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
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10
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Climent B, Moreno L, Martínez P, Contreras C, Sánchez A, Pérez-Vizcaíno F, García-Sacristán A, Rivera L, Prieto D. Upregulation of SK3 and IK1 channels contributes to the enhanced endothelial calcium signaling and the preserved coronary relaxation in obese Zucker rats. PLoS One 2014; 9:e109432. [PMID: 25302606 PMCID: PMC4193814 DOI: 10.1371/journal.pone.0109432] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 09/01/2014] [Indexed: 12/19/2022] Open
Abstract
Background and Aims Endothelial small- and intermediate-conductance KCa channels, SK3 and IK1, are key mediators in the endothelium-derived hyperpolarization and relaxation of vascular smooth muscle and also in the modulation of endothelial Ca2+ signaling and nitric oxide (NO) release. Obesity is associated with endothelial dysfunction and impaired relaxation, although how obesity influences endothelial SK3/IK1 function is unclear. Therefore we assessed whether the role of these channels in the coronary circulation is altered in obese animals. Methods and Results In coronary arteries mounted in microvascular myographs, selective blockade of SK3/IK1 channels unmasked an increased contribution of these channels to the ACh- and to the exogenous NO- induced relaxations in arteries of Obese Zucker Rats (OZR) compared to Lean Zucker Rats (LZR). Relaxant responses induced by the SK3/IK1 channel activator NS309 were enhanced in OZR and NO- endothelium-dependent in LZR, whereas an additional endothelium-independent relaxant component was found in OZR. Fura2-AM fluorescence revealed a larger ACh-induced intracellular Ca2+ mobilization in the endothelium of coronary arteries from OZR, which was inhibited by blockade of SK3/IK1 channels in both LZR and OZR. Western blot analysis showed an increased expression of SK3/IK1 channels in coronary arteries of OZR and immunohistochemistry suggested that it takes place predominantly in the endothelial layer. Conclusions Obesity may induce activation of adaptive vascular mechanisms to preserve the dilator function in coronary arteries. Increased function and expression of SK3/IK1 channels by influencing endothelial Ca2+ dynamics might contribute to the unaltered endothelium-dependent coronary relaxation in the early stages of obesity.
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Affiliation(s)
- Belén Climent
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
- * E-mail: (BC); (DP)
| | - Laura Moreno
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain
| | - Pilar Martínez
- Departamento de Anatomía y Anatomía Patológica Comparadas, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain
| | - Cristina Contreras
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Ana Sánchez
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | | | | | - Luis Rivera
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Dolores Prieto
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
- * E-mail: (BC); (DP)
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11
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Seçilmiş MA, Özü ÖY, Kıroğlu OE, Şingirik E, Büyükafşar K. The production of vasoconstriction-induced residual NO modulates perfusion pressure in rat mesenteric vascular bed. Perfusion 2014; 29:488-95. [DOI: 10.1177/0267659114524263] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In the presence of nitric oxide synthase (NOS) inhibitors, the contribution of residual NO to endothelium-dependent relaxation induced by chemical agonists acetylcholine and bradykinin has been documented in resistance vessels. However, the contribution of residual NO to the vasodilatation in response to pressure and fluid shear stress is not well understood. In this study, to demonstrate the activity of residual NO, we applied a NO scavenger, hydroxocobalamin (HCX), on the phenylephrine-induced increase in perfusion pressure in the presence of NOS inhibitors, Nω-nitro-L-arginine (L-NA) or Nω-nitro-L-arginine methyl ester (L-NAME) in the rat perfused mesenteric bed. The perfusion pressure was increased by phenylephrine (1-2 µM), an α1-adrenoceptor agonist. This increase was augmented by the addition of L-NA or L-NAME. In the presence of any NOS inhibitors, the application of hydroxocobalamin (100 µM) further increased the perfusion pressure. The removal of endothelium by saponin (50 mg/L) and the use of a non-selective protein kinase inhibitor, staurosporine (5 nM), and a tyrosine kinase inhibitor, erbstatin A (30 µM), but not a calmodulin inhibitor, calmidazolium (0.5 µM), inhibited the additional pressor responses induced by L-NA or L-NAME and a combination of either of them with hydroxocobalamine. These findings show that there could be a NOS inhibitor-resistant residual NO production in response to pressure in the rat mesenteric vascular bed. This residual NO production may be associated with the activation of tyrosine kinase and protein kinases, but not calmodulin. Finally, this pressure-induced residual NO exerts a modulatory role against vasoconstriction induced by phenylephrine.
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Affiliation(s)
- MA Seçilmiş
- Department of Pharmacology, Çukurova University, Medical School, Adana, Turkey
| | - ÖY Özü
- Department of Pharmacology, Çukurova University, Medical School, Adana, Turkey
| | - OE Kıroğlu
- Department of Pharmacology, Çukurova University, Medical School, Adana, Turkey
| | - E Şingirik
- Department of Pharmacology, Çukurova University, Medical School, Adana, Turkey
| | - K Büyükafşar
- Department of Pharmacology, Medical Faculty Mersin University, Campus Yenişehir, Mersin, Turkey
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12
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Chan E, Chan JYY, Wu JH, Wan CW, Leung GPH, Lee SMY, Kwan YW, Chan SW. Serum nitric oxide synthase activity is a novel predictor of impaired vasorelaxation in rats. Clin Exp Pharmacol Physiol 2012; 39:894-6. [DOI: 10.1111/j.1440-1681.2012.05748.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Enoch Chan
- State Key Laboratory of Chinese Medicine and Molecular Pharmacology; Department of Applied Biology and Chemical Technology; The Hong Kong Polytechnic University; Hong Kong; China
| | - Janet Yuen-Yan Chan
- State Key Laboratory of Chinese Medicine and Molecular Pharmacology; Department of Applied Biology and Chemical Technology; The Hong Kong Polytechnic University; Hong Kong; China
| | - Jian-Hong Wu
- State Key Laboratory of Chinese Medicine and Molecular Pharmacology; Department of Applied Biology and Chemical Technology; The Hong Kong Polytechnic University; Hong Kong; China
| | - Chun-Wai Wan
- State Key Laboratory of Chinese Medicine and Molecular Pharmacology; Department of Applied Biology and Chemical Technology; The Hong Kong Polytechnic University; Hong Kong; China
| | - George Pak-Heng Leung
- Department of Pharmacology and Pharmacy; Faculty of Medicine; The University of Hong Kong; Hong Kong; China
| | - Simon Ming-Yuen Lee
- State Key Laboratory of Quality Research in Chinese Medicine; University of Macau; Macao; China
| | - Yiu-Wa Kwan
- School of Biomedical Sciences; Faculty of Medicine; The Chinese University of Hong Kong; Hong Kong; China
| | - Shun-Wan Chan
- State Key Laboratory of Chinese Medicine and Molecular Pharmacology; Department of Applied Biology and Chemical Technology; The Hong Kong Polytechnic University; Hong Kong; China
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13
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Botden IPG, Batenburg WW, de Vries R, Langendonk JG, Sijbrands EJG, Danser AHJ. Nitrite- and nitroxyl-induced relaxation in porcine coronary (micro-) arteries: underlying mechanisms and role as endothelium-derived hyperpolarizing factor(s). Pharmacol Res 2012; 66:409-18. [PMID: 22902525 DOI: 10.1016/j.phrs.2012.07.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 07/30/2012] [Accepted: 07/30/2012] [Indexed: 11/15/2022]
Abstract
To investigate the vasorelaxant efficacy of nitrite and nitroxyl (HNO) in porcine coronary (micro)arteries (PC(M)As), evaluating their role as endothelium-derived hyperpolarizing factors (EDHFs), preconstricted PCAs and PCMAs were exposed to UV light (a well-known inductor of nitrite; wave-length: 350-370nm), nitrite, the HNO donor Angeli's salt, or bradykinin. UV light-induced relaxation of PCAs increased identically after endothelium removal and endothelial nitric oxide (NO) synthase (eNOS) blockade. UV light-induced relaxation diminished during Na(+)-K(+)-ATPase inhibition and S-nitrosothiol-depletion, and disappeared during NO scavenging with hydroxocobalamin or soluble guanylyl cyclase (sGC) inhibition with ODQ. Nitrite-induced relaxation of PCAs required millimolar levels, i.e., >1000 times endogenous vascular nitrite. Angeli's salt relaxed PCMAs more potently than PCAs, and this was due to the fact that HNO directly activated sGC in PCMAs, whereas in PCAs this occurred following its conversion to NO only. sGC activation by NO/HNO resulted in Na(+)-K(+)-ATPase stimulation and K(v) channel activation. The HNO scavenger l-cysteine blocked bradykinin-induced relaxation in PCAs, and potentiated it in PCMAs. The latter did not occur in the presence of hydroxocobalamin, suggesting that it depended on l-cysteine-induced generation of vasorelaxant S-nitrosothiols. In all experimental setups, incubation with red wine extract mimicked the effects of ODQ. In conclusion, nitrite, via its conversion to NO and S-nitrosothiols, and HNO, either directly, or via its conversion to NO, mediate relaxant effects involving the sGC-cGMP pathway, Na(+)-K(+)-ATPase and/or K(v) channels. Red wine extract counteracts these beneficial effects. NO blocks nitrite activation, and HNO, but not nitrite, may act as EDHF in the coronary vascular bed.
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Affiliation(s)
- Ilse P G Botden
- Division of Pharmacology and Vascular Medicine, Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
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14
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Leo CH, Joshi A, Hart JL, Woodman OL. Endothelium-dependent nitroxyl-mediated relaxation is resistant to superoxide anion scavenging and preserved in diabetic rat aorta. Pharmacol Res 2012; 66:383-91. [PMID: 22898326 DOI: 10.1016/j.phrs.2012.07.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 07/30/2012] [Accepted: 07/30/2012] [Indexed: 10/28/2022]
Abstract
The aim of the study was to investigate whether diabetes-induced oxidant stress affects the contribution of nitroxyl (HNO) to endothelium-dependent relaxation in the rat aorta. Organ bath techniques were employed to determine vascular function of rat aorta. Pharmacological tools (3mM l-cysteine, 5mM 4-aminopyridine (4-AP), 200μM carboxy-PTIO and 100μM hydroxocobalamin, HXC) were used to distinguish between NO and HNO-mediated relaxation. Superoxide anion levels were determined by lucigenin-enhanced chemiluminescence. In the diabetic aorta, where there is increased superoxide anion production, responses to the endothelium-dependent relaxant ACh were not affected when the contribution of NO to relaxation was abolished by either HXC or carboxy-PTIO, indicating a preserved HNO-mediated relaxation. Conversely, when the contribution of HNO was inhibited with l-cysteine or 4-AP, the sensitivity and maximum relaxation to ACh was significantly decreased, suggesting that the contribution of NO was impaired by diabetes. Furthermore, whereas HNO appears to be derived from eNOS in normal aorta, in the diabetic aorta it may also arise from an eNOS-independent source, perhaps derived from nitrosothiol stores. Similarly, exposure to the superoxide anion generator, pyrogallol (100μM) significantly reduced the sensitivity to the NO donor, DEANONOate and ACh-induced NO-mediated relaxation but had no effect on responses to the HNO donor, Angeli's salt and ACh-induced HNO-mediated relaxation in the rat aorta. These findings demonstrate that NO-mediated relaxation is impaired during oxidative stress but the HNO component of relaxation is preserved under those conditions.
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Affiliation(s)
- C H Leo
- School of Medical Sciences, Health Innovations Research Institute, RMIT University, Bundoora, Victoria, Australia
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15
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Zhou Z, Hemradj V, de Beer VJ, Gao F, Hoekstra M, Merkus D, Duncker DJ. Cytochrome P-450 2C9 exerts a vasoconstrictor influence on coronary resistance vessels in swine at rest and during exercise. Am J Physiol Heart Circ Physiol 2012; 302:H1747-55. [PMID: 22307673 DOI: 10.1152/ajpheart.00648.2011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A significant endothelium-dependent vasodilation persists after inhibition of nitric oxide synthase (NOS) and cyclooxygenase (COX) in the coronary vasculature, which has been linked to the activation of cytochrome P-450 (CYP) epoxygenases expressed in endothelial cells and subsequent generation of vasodilator epoxyeicosatrienoic acids. Here, we investigated the contribution of CYP 2C9 metabolites to regulation of porcine coronary vasomotor tone in vivo and in vitro. Twenty-six swine were chronically instrumented. Inhibition of CYP 2C9 with sulfaphenazole (5 mg/kg iv) alone had no effect on bradykinin-induced endothelium-dependent coronary vasodilation in vivo but slightly attenuated bradykinin-induced vasodilation in the presence of combined NOS/COX blockade with N(ω)-nitro-L-arginine (20 mg/kg iv) and indomethacin (10 mg/kg iv). Sulfaphenazole had minimal effects on coronary resistance vessel tone at rest or during exercise. Surprisingly, in the presence of combined NOS/COX blockade, a significant coronary vasodilator response to sulfaphenzole became apparent, both at rest and during exercise. Subsequently, we investigated in isolated porcine coronary small arteries (∼250 μm) the possible involvement of reactive oxygen species (ROS) in the paradoxical vasoconstrictor influence of CYP 2C9 activity. The vasodilation by bradykinin in vitro in the presence of NOS/COX blockade was markedly potentiated by sulfaphenazole under control conditions but not in the presence of the ROS scavenger N-(2-mercaptoproprionyl)-glycine. In conclusion, CYP 2C9 can produce both vasoconstrictor and vasodilator metabolites. Production of these metabolites is enhanced by combined NOS/COX blockade and is critically dependent on the experimental conditions. Thus production of vasoconstrictors slightly outweighed the production of vasodilators at rest and during exercise. Pharmacological stimulation with bradykinin resulted in vasodilator CYP 2C9 metabolite production when administered in vivo, whereas vasoconstrictor CYP 2C9 metabolites, most likely ROS, were dominant when administered in vitro.
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Affiliation(s)
- Zhichao Zhou
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Cardiovascular Research School Erasmus University Rotterdam, Erasmus Medical Center, University Medical Center Rotterdam, Rotterdam, The Netherlands
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16
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Deniset JF, Hedley TE, Dibrov E, Pierce GN. Chlamydophila pneumoniae infection induces alterations in vascular contractile responses. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 180:1264-1272. [PMID: 22214836 DOI: 10.1016/j.ajpath.2011.11.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 10/11/2011] [Accepted: 11/11/2011] [Indexed: 11/29/2022]
Abstract
Chlamydophila pneumoniae infection has been associated in previous studies with coronary artery disease. The live bacterium has been detected within atherosclerotic plaques and can induce the structural remodeling of the vessel wall. However, the direct effects of infection on the contractile characteristics of the arteries remain unknown. Left anterior descending coronary arteries isolated from porcine hearts were dissected and placed in culture medium for 72 hours before infection with C. pneumoniae. Contractile responses to high molar KCl and u46619 levels and relaxation responses to bradykinin and sodium nitroprusside were assessed at days 5 and 10 postinfection. C. pneumoniae induced decreases in both KCl- and u46619-induced contractile responses at both time points. The altered contractile responses coincided with a down-regulation of L-type Ca(2+) channels at both time points and inositol 1,4,5-triphosphate receptor (IP3R) levels at day 10 postinfection. Infection also induced attenuation of the endothelial-dependent relaxation response to bradykinin at day 10 postinfection. A decrease in endothelial nitric oxide synthase expression levels was noted at day 10 postinfection. Furthermore, an increase in superoxide production combined with an increase in p22phox expression levels was also observed at this time point. These findings indicate that C. pneumoniae infection can directly alter the vascular contractile responses in porcine coronary arteries, providing additional evidence for the role of C. pneumoniae infection in cardiovascular disease.
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Affiliation(s)
- Justin F Deniset
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, Department of Physiology, Faculties of Medicine and Pharmacy, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Thomas E Hedley
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, Department of Physiology, Faculties of Medicine and Pharmacy, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Elena Dibrov
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, Department of Physiology, Faculties of Medicine and Pharmacy, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Grant N Pierce
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, Department of Physiology, Faculties of Medicine and Pharmacy, University of Manitoba, Winnipeg, Manitoba, Canada.
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17
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Erdös EG, Tan F, Skidgel RA. Angiotensin I-converting enzyme inhibitors are allosteric enhancers of kinin B1 and B2 receptor function. Hypertension 2010; 55:214-20. [PMID: 20065150 DOI: 10.1161/hypertensionaha.109.144600] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The beneficial effects of angiotensin I-converting enzyme (ACE) inhibitors go beyond the inhibition of ACE to decrease angiotensin (Ang) II or increase kinin levels. ACE inhibitors also affect kinin B1 and B2 receptor (B1R and B2R) signaling, which may underlie some of their therapeutic usefulness. They can indirectly potentiate the actions of bradykinin (BK) and ACE-resistant BK analogs on B2Rs to elevate arachidonic acid and NO release in laboratory experiments. Studies indicate that ACE inhibitors and some Ang metabolites increase B2R functions as allosteric enhancers by inducing a conformational change in ACE. This is transmitted to B2Rs via heterodimerization with ACE on the plasma membrane of cells. ACE inhibitors are also agonists of the B1R, at a Zn-binding sequence on the second extracellular loop that differs from the orthosteric binding site of the des-Arg-kinin peptide ligands. Thus, ACE inhibitors act as direct allosteric B1R agonists. When ACE inhibitors enhance B2R and B1R signaling, they augment NO production. Enhancement of B2R signaling activates endothelial NO synthase, yielding a short burst of NO; activation of B1Rs results in a prolonged high output of NO by inducible NO synthase. These actions, outside inhibiting peptide hydrolysis, may contribute to the pleiotropic therapeutic effects of ACE inhibitors in various cardiovascular disorders.
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Affiliation(s)
- Ervin G Erdös
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Ill 60612, USA.
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18
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Light-induced vs. bradykinin-induced relaxation of coronary arteries: do S-nitrosothiols act as endothelium-derived hyperpolarizing factors? J Hypertens 2009; 27:1631-40. [PMID: 19421072 DOI: 10.1097/hjh.0b013e32832bff54] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Light-induced relaxation depends on S-nitrosothiols. S-Nitrosothiols may also serve as endothelium-derived hyperpolarizing factors, mediating the relaxant response of porcine coronary arteries (PCAs) to bradykinin. Here we compared the mechanism of light-induced and bradykinin-induced PCA relaxation. METHODS PCAs were mounted in organ baths in the dark, preconstricted and exposed to polychromatic light (5 min) or 100 nmol/l bradykinin. RESULTS Light relaxed PCAs by maximally 71 +/- 1%. S-Nitrosothiol depletion abolished this relaxation. Relaxations diminished following repetitive light exposures, particularly if the dark periods between the light exposures were less than 10 min, and increased following endothelium removal or nitric oxide synthase blockade with N(omega)-nitro-L-arginine methyl ester (L-NAME), despite the prevention of guanosine-3',5'-cyclic monophosphate generation by the latter two procedures. Thus, reloading of the storage pools occurs in the dark, endothelial nitric oxide inhibits this process and photorelaxation does not depend on guanosine-3',5'-cyclic monophosphate. Bradykinin relaxed PCAs by 69 +/- 3%. The nitric oxide scavenger hydroxocobalamin and the Na+-K+ ATPase inhibitor ouabain abolished the responses to bradykinin and light. The guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one abolished the response to light, and, like L-NAME, blocked the response to bradykinin by more than 50%. On top of L-NAME, intermediate and small conductance Ca2+-dependent K+ channel (IKCa/SKCa) blockade further reduced the response to bradykinin and enhanced photorelaxation. CONCLUSION Photorelaxation depends on stored S-nitrosothiols and their release/synthesis is negatively affected by endothelial nitric oxide and IKCa/SKCa. S-Nitrosothiols activate endothelial IKCa/SKCa and, via guanylyl cyclase, smooth muscle Na+-K+ ATPase. Thus, they possess all properties of a bradykinin-induced endothelium-derived hyperpolarizing factor.
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Devil and angel in the renin-angiotensin system: ACE-angiotensin II-AT1 receptor axis vs. ACE2-angiotensin-(1-7)-Mas receptor axis. Hypertens Res 2009; 32:533-6. [PMID: 19461648 PMCID: PMC7091931 DOI: 10.1038/hr.2009.74] [Citation(s) in RCA: 216] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recent studies have established a new regulatory axis in the renin–angiotensin system (RAS). In this axis, angiotensin (Ang)-(1–7) is finally produced from Ang I or Ang II by the catalytic activity of angiotensin-converting enzyme 2 (ACE2). Ang-(1–7) shows actions different from those of AT1 receptor stimulation, such as vasodilatation, natriuresis, anti-proliferation and an increase in the bradykinin–NO (nitric oxide) system. As the catalytic efficiency of ACE2 is approximately 400-fold higher with Ang II as a substrate than with Ang I, this axis is possibly acting as a counter-regulatory system against the ACE/Ang II/AT1 receptor axis. The signaling pathway of the ACE2–Ang-(1–7) axis has not yet been totally and clearly understood. However, a recent report suggests that the Mas oncogene acts as a receptor for Ang-(1–7). Intracellular signaling through Mas is not clear yet. Several factors such as Akt phosphorylation, protein kinase C activation and mitogen-activated protein (MAP) kinase inhibition seem to be involved in this signaling pathway. Further investigations are needed to clarify the regulation and mechanism of action of ACE2 and Ang-(1–7). However, this second axis through ACE2 and Ang-(1–7) in RAS can be an important target for the therapy of cardiovascular and metabolic disorders.
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McKenzie C, MacDonald A, Shaw AM. Mechanisms of U46619-induced contraction of rat pulmonary arteries in the presence and absence of the endothelium. Br J Pharmacol 2009; 157:581-96. [PMID: 19389160 DOI: 10.1111/j.1476-5381.2008.00084.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND AND PURPOSE Thromboxane A(2) and endothelial dysfunction are implicated in the development of pulmonary hypertension. The receptor-transduction pathway for U46619 (9,11-dideoxy-9 alpha, 11 alpha-methanoepoxy prostaglandin F(2 alpha))-induced contraction was examined in endothelium-intact (E+) and denuded (E-) rat pulmonary artery rings. EXPERIMENTAL APPROACH Artery rings were mounted on a wire myograph under a tension of 7-7.5 mN at 37 degrees C and gassed with 95% O(2)/5% CO(2). Isometric recording was made by using Powerlab data collection and Chart 5 software. KEY RESULTS Both E+ and E- contractile responses were sensitive to Rho-kinase inhibition and the chloride channel blocker NPPB [5-nitro-2-(3-phenylpropylamino)benzoic acid]. The E+ response was sensitive to the store-operated calcium channel blockers SKF-96365 {1-[B-[3-(4-methoxyphenyl)propoxy]-4-methoxy-phenethyl]-1H-imidazole hydrochloride} and 2-APB (2-amino ethoxy diphenylborate) (75-100 micromol x L(-1)). The E- response was sensitive to 2-APB (10-30 micromol x L(-1)), a putative IP(3) receptor antagonist, and the calcium and chloride channel blockers nifedipine, DIDS (4,4'-diisothiocyanostilbene-2,2'-disulphonic acid) and niflumic acid but was insensitive to SKF-96365. Inhibiting K(V) with 4-AP in E+ rings exposed a contraction sensitive to nifedipine, DIDS and niflumic acid, whereas inhibiting BK(Ca) exposed a contraction sensitive to mibefradil, DIDS and niflumic acid. This indicates that removal of the endothelium allows the TP receptor to inhibit K(V), which may involve coupling to phospholipase C, because inhibition of phospholipase C with U73122 (1-[6-[[(17beta)-3-methoxyestra-1,3,5(10)-trien-17-y]amino]hexyl]- 1H-pyrrole-2,5-dione) switched the E- pathway to the E+ pathway. CONCLUSIONS AND IMPLICATIONS The results from this study indicate that distinct transduction pathways can be employed by the TP receptor to produce contraction and that the endothelium is able to influence the coupling of the TP receptor.
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Affiliation(s)
- C McKenzie
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, UK
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21
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Leo MDM, Siddegowda YKB, Kumar D, Tandan SK, Sastry KVH, Prakash VR, Mishra SK. Role of nitric oxide and carbon monoxide in N(omega)-Nitro-L-arginine methyl ester-resistant acetylcholine-induced relaxation in chicken carotid artery. Eur J Pharmacol 2008; 596:111-7. [PMID: 18713623 DOI: 10.1016/j.ejphar.2008.07.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 07/22/2008] [Accepted: 07/24/2008] [Indexed: 10/21/2022]
Abstract
The current study examined the hypothesis that acetylcholine-induced N(omega)-Nitro-L-arginine methyl ester (L-NAME)-resistant endothelium-dependent relaxations in the chicken carotid artery are mediated by nitric oxide and carbon monoxide. Acetylcholine (1 nM-3 microM) caused a concentration-dependent relaxation (pD(2) 6.81+/-0.05, R(max) 115+/-3%) of the artery segments precontracted with phenylephrine (3 microM). L-NAME (1 mM) decreased the sensitivity (pD(2) 6.44+/-0.06), but not the efficacy (R(max) 108+/-3%) of acetylcholine. It also partially decreased the acetylcholine (3 microM)-stimulated nitrite release. While treatment with N(omega)-Nitro-L-arginine (l-NNA; 1 mM) plus L-NAME (1 mM) decreased the acetylcholine-stimulated nitrite release to the basal level, it moderately inhibited (R(max) 77+/-3%) the maximal relaxation elicited with the muscarinic agonist. 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO; 100 microM) a specific scavenger of nitric oxide (NO) plus the two NOS inhibitors further decreased the acetylcholine-evoked relaxation (R(max) 34+/-2%). Although soluble guanylyl cyclase (sGC) inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; 10 microM) markedly inhibited the acetylcholine-stimulated increase in tissue cGMP to less than the basal levels, it only decreased the sensitivity, but not the efficacy of the agonist either in the presence or absence of L-NAME (1 mM). Zinc Protoporphyrin-IX (ZnPP; 10 microM), a hemeoxygenase (HO) inhibitor, partially inhibited (R(max) 72+/-3%) the L-NAME-resistant acetylcholine-induced relaxations. A combined treatment of the arterial rings with L-NAME, l-NNA, PTIO and ZnPP nearly abolished (R(max) 7+/-0.9%) the vasodilator responses to acetylcholine. Endothelium removal abolished the relaxation response to acetylcholine. In conclusion, it is suggested that the acetylcholine-induced L-NAME-resistant relaxation is primarily, mediated by NO with a small but significant contribution from endothelium-derived carbon monoxide in the chicken carotid artery.
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Affiliation(s)
- Marie Dennis Marcus Leo
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India
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Castro-Chaves P, Soares S, Fontes-Carvalho R, Leite-Moreira AF. Negative inotropic effect of selective AT2 receptor stimulation and its modulation by the endocardial endothelium. Eur J Pharmacol 2008; 578:261-9. [DOI: 10.1016/j.ejphar.2007.09.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Revised: 09/17/2007] [Accepted: 09/18/2007] [Indexed: 10/22/2022]
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Pasgaard T, Stankevicius E, Jørgensen MM, Ostergaard L, Simonsen U, Frøbert O. Hyperoxia reduces basal release of nitric oxide and contracts porcine coronary arteries. Acta Physiol (Oxf) 2007; 191:285-96. [PMID: 17784906 DOI: 10.1111/j.1748-1716.2007.01745.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM The purpose of the present study was to investigate whether changes in nitric oxide (NO) concentration is involved in hyperoxia-induced vasoconstriction in porcine conduit coronary arteries. METHODS The effect of hyperoxia on NO release and vasoconstriction was evaluated by tension recording, microsensor measurements, and immunoblotting in porcine conduit coronary arteries contracted with U46619 or 5-hydroxytryptamine. RESULTS In endothelium-intact segments exchanging 20% O2, 5% CO2, 75% N2 (normoxia) for 95% O2, 5% CO2 (hyperoxia) increased contraction. In segments without endothelium hyperoxia-evoked contraction was abolished, but restored by an encircling donor segment with endothelium. An inhibitor of NOS, asymmetric dimethylarginine (ADMA, 300 mum), reduced hyperoxic contraction and basal NO concentration by, respectively, 38 +/- 12% and 46 +/- 3% (P < 0.05, n = 9). A NO donor, S-nitroso-N-acetylpenicillamine (SNAP), increased NO concentration and evoked relaxation to the same levels in normoxic and hyperoxic conditions. beta-actin and endothelial NO synthase (eNOS) protein expression was similar in normoxic and hyperoxic arterial segments. Phosphorylation of eNOS was unaltered in normoxia vs. hyperoxia, but phosphorylation of eNOS-Ser(1177) was increased and phosphorylation of eNOS-Thr(495) decreased by U46619. Blockers of ATP-sensitive, voltage-dependent and calcium-activated K+ channels did not change hyperoxic contraction. However, high extracellular K+ concentration or a second and third exposure to hyperoxia decreased contraction. CONCLUSION The present study provides direct evidence that hyperoxia reduces basal release of NO leading to depletable endothelium-dependent vasoconstriction in porcine coronary arteries independent of changes in eNOS phosphorylation.
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Affiliation(s)
- T Pasgaard
- Department of Pharmacology, University of Aarhus, Aarhus C, Denmark
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Hashmi-Hill MP, Sandock K, Bates JN, Robertson TP, Lewis SJ. Flavin adenine dinucleotide may release preformed stores of nitrosyl factors from the vascular endothelium of conscious rats. J Cardiovasc Pharmacol 2007; 50:142-54. [PMID: 17703130 DOI: 10.1097/fjc.0b013e31805c1646] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
This study determined whether flavin adenine dinucleotide (FAD) may elicit vasodilation in conscious rats via release of preformed endothelium-derived nitrosyl factors. Injections 1-6 (inj(1-6)) of FAD (2.5 micromol/kg, IV) elicited pronounced and equivalent vasodilator responses in saline-treated rats. Inj(1) of FAD elicited pronounced vasodilation in L-NAME-treated rats pretreated with the nitric oxide (NO) synthesis inhibitor, NG-nitro-L-arginine (L-NAME; 50 micromol/kg, IV), whereas Inj(2-6) elicited progressively smaller responses such that inj(6) elicited minor responses. The vasodilator responses elicited by the endothelium-dependent agonist, acetylcholine, were markedly attenuated in L-NAME-treated rats that had received inj(1-6) of FAD but not in saline-treated rats that had received inj(1-6) of FAD. The vasodilator actions of L-S-nitrosocysteine and the NO donor, sodium nitroprusside, were not diminished after the injections of FAD in saline- or in L-NAME-treated rats. Binding studies demonstrated that the densities of muscarinic M3 receptors were increased in thoracic aorta endothelium of rats treated with L-NAME + inj(1-6) of saline or L-NAME + inj(1-6) of FAD as compared to rats treated with saline + inj(1-6) of saline or saline + inj(1-6) of FAD. The progressive loss of response to injections of FAD in L-NAME-treated rats coupled with the loss of response to acetylcholine suggests that FAD elicits the use-dependent depletion of vesicular pools of nitrosyl factors in endothelial cells that cannot be replenished in the absence of NO synthesis.
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Affiliation(s)
- Maleka P Hashmi-Hill
- Department of Physiology and Pharmacology, University of Georgia, Athens, Georgia 30602-7389, USA
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Agata J, Ura N, Yoshida H, Shinshi Y, Sasaki H, Hyakkoku M, Taniguchi S, Shimamoto K. Olmesartan is an angiotensin II receptor blocker with an inhibitory effect on angiotensin-converting enzyme. Hypertens Res 2007; 29:865-74. [PMID: 17345786 DOI: 10.1291/hypres.29.865] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Angiotensin II receptor blockers (ARBs) are widely used for the treatment of hypertension. It is believed that treatment with an ARB increases the level of plasma angiotensin II (Ang II) because of a lack of negative feedback on renin activity. However, Ichikawa (Hypertens Res 2001; 24: 641-646) reported that long-term treatment of hypertensive patients with olmesartan resulted in a reduction in plasma Ang II level, though the mechanism was not determined. It has been reported that angiotensin 1-7 (Ang-(1-7)) potentiates the effect of bradykinin and acts as an angiotensin-converting enzyme (ACE) inhibitor. It is known that ACE2, which was discovered as a novel ACE-related carboxypeptidase in 2000, hydrolyzes Ang I to Ang-(1-9) and also Ang II to Ang-(1-7). It has recently been reported that olmesartan increases plasma Ang-(1-7) through an increase in ACE2 expression in rats with myocardial infarction. We hypothesized that over-expression of ACE2 may be related to a reduction in Ang II level and the cardioprotective effect of olmesartan. Administration of 0.5 mg/kg/day of olmesartan for 4 weeks to 12-week-old stroke-prone spontaneously hypertensive rats (SHRSP) significantly reduced blood pressure and left ventricular weight compared to those in SHRSP given a vehicle. Co-administration of olmesartan and (D-Ala7)-Ang-(1-7), a selective Ang-(1-7) antagonist, partially inhibited the effect of olmesartan on blood pressure and left ventricular weight. Interestingly, co-administration of (D-Ala7)-Ang-(1-7) with olmesartan significantly increased the plasma Ang II level (453.2+/-113.8 pg/ml) compared to olmesartan alone (144.9+/-27.0 pg/ml, p<0.05). Moreover, olmesartan significantly increased the cardiac ACE2 expression level compared to that in Wistar Kyoto rats and SHRSP treated with a vehicle. Olmesartan significantly improved cardiovascular remodeling and cardiac nitrite/ nitrate content, but co-administration of olmesartan and (D-Ala7)-Ang-(1-7) partially reversed this anti-remodeling effect and the increase in nitrite/nitrate. These findings suggest that olmesartan may exhibit an ACE inhibitory action in addition to an Ang II receptor blocking action, prevent an increase in Ang II level, and protect cardiovascular remodeling through an increase in cardiac nitric oxide production and endogenous Ang-(1-7) via over-expression of ACE2.
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Affiliation(s)
- Jun Agata
- Second Department of Internal Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan.
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Greco AJ, Master RG, Fokin A, Baber SR, Kadowitz PJ. Angiotensin-(1-7) potentiates responses to bradykinin but does not change responses to angiotensin I. Can J Physiol Pharmacol 2007; 84:1163-75. [PMID: 17218981 DOI: 10.1139/y06-053] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Angiotensin-(1-7) (Ang-(1-7)), a bioactive peptide in the renin-angiotensin system, has counterregulatory actions to angiotensin II (Ang II). However, the mechanism by which Ang-(1-7) enhances vasodepressor responses to bradykinin (BK) is not well understood. In the present study, the effects of Ang-(1-7) on responses to BK, BK analogs, angiotensin I (Ang I), and Ang II were investigated in the anesthetized rat. The infusion of Ang-(1-7) (55 pmol/min i.v.) enhanced decreases in systemic arterial pressure in response to i.v. injections of BK and the BK analogs [Hyp3, Tyr(Me)8]-bradykinin (HT-BK) and [Phe8psi (CH2-NH) Arg9]-bradykinin (PA-BK) without altering pressor responses to Ang I or II, or depressor responses to acetylcholine and sodium nitroprusside. The angiotensin-converting enzyme (ACE) inhibitor enalaprilat enhanced responses to BK and the BK analog HT-BK without altering responses to PA-BK and inhibited responses to Ang I. The potentiating effects of Ang-(1-7) and enalaprilat on responses to BK were not attenuated by the Ang-(1-7) receptor antagonist A-779. Ang-(1-7)- and ACE inhibitor-potentiated responses to BK were attenuated by the BK B2 receptor antagonist Hoe 140. The cyclooxygenase inhibitor sodium meclofenamate had no significant effect on responses to BK or Ang-(1-7)-potentiated BK responses. These results suggest that Ang-(1-7) potentiates responses to BK by a selective B2 receptor mechanism that is independent of an effect on Ang-(1-7) receptors, ACE, or cyclooxygenase product formation. These data suggest that ACE inhibitor-potentiated responses to BK are not mediated by an A-779-sensitive mechanism and are consistent with the hypothesis that enalaprilat-induced BK potentiation is due to decreased BK inactivation.
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Affiliation(s)
- A Joel Greco
- Department of Pharmacology, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
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Abstract
Inhibition of the angiotensin-converting enzyme (ACE) protects against the progression of several cardiovascular diseases. Because of its dual role in regulating angiotensin II and bradykinin levels, the positive clinical effects of ACE inhibitors were thought to be the consequence of concomitant reductions in the production of angiotensin II and the degradation of bradykinin. Recent evidence suggests that some of the beneficial effects of ACE inhibitors on cardiovascular function and homeostasis can be attributed to novel mechanisms. These include the accumulation of the ACE substrate N-acetyl-seryl-aspartyl-lysyl-proline, which blocks collagen deposition in the injured heart, as well as the activation of an ACE signaling cascade that involves the activation of the kinase CK2 and the c-Jun N-terminal kinase in endothelial cells and leads to changes in gene expression. Moreover, at least one other ACE homologue (ACE2) is proposed to counteract the detrimental effects associated with the activation of the classical renin-angiotensin system. These data reveal hitherto unexpected levels of internal regulation of the renin-angiotensin system.
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Affiliation(s)
- Ingrid Fleming
- Vascular Signalling Group, Institut für Kardiovaskuläre Physiologie, Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany.
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Abstract
The main aim of this study was to determine the effects of the lipophobic electron acceptor, nitroblue tetrazolium (NBT), on the vasodilator responses elicited by femoral vein injections of L- and D-S-nitrosocysteine (L- and D-SNC), L- and D-S-nitroso-beta,beta-dimethylcysteine (L- and D-SNPEN) and the nitric oxide (NO) donor, MAHMA NONOate, in pentobarbital-anesthetized rats. L- and D-SNC, L- and D-SNPEN, and MAHMA NONOate elicited dose-dependent falls in mean arterial blood pressure (MAP), and hindquarter (HQR), renal (RR), and mesenteric (MR) vascular resistances. The L-SNC- and L-SNPEN-induced depressor and vasodilator responses were markedly attenuated after injection of NBT. The D-SNC- and D-SNPEN-induced falls in mean arterial pressure, hindquarter, and mesenteric vascular resistances were also reduced after injection of nitroblue tetrazolium whereas the falls in renal resistances were not affected. However, nitroblue tetrazolium inhibited the L-SNC and L-SNPEN responses much more profoundly than the D-SNC and D-SNPEN responses in each vascular bed. In contrast, the MAHMA NONOate-induced responses were not attenuated by nitroblue tetrazolium. This study demonstrates that nitroblue tetrazolium attenuates L- and D-SNC-and L- and D-SNPEN- mediated but not NO-mediated vasodilation. The lack of effects of NBT on the NO responses suggests that NBT does not interfere with the intracellular mechanisms by which NO relaxes vascular smooth muscle. The more pronounced effects of NBT on the vasodilator effects of L-SNC and L-SNPEN than D-SNC and D-SNPEN suggests that these stereoisomers differentially interact with stereoselective S-nitrosothiol recognition sites in the vasculature and that these sites (or their signaling elements) contain thiol residues that may be susceptible to occupation and/or oxidation (ie, disulfide-bond formation) by nitroblue tetrazolium.
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Affiliation(s)
- Stephen J Lewis
- Department of Physiology and Pharmacology, University of Georgia, Athens, GA 30602, USA.
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Ansar MM, Ansari M. Nitric oxide involvement in pancreatic beta cell apoptosis by glibenclamide. Nitric Oxide 2005; 14:39-44. [PMID: 16256381 DOI: 10.1016/j.niox.2005.09.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 09/04/2005] [Accepted: 09/09/2005] [Indexed: 01/09/2023]
Abstract
Glibenclamide as a second-generation compound of sulfonylurea has widely been used in the treatment of type 2 diabetes patients. It has been shown that it induces apoptosis in beta cells, which is partially mediated by Ca(2+) influx. Here, we investigated the role of nitric oxide (NO) and nitric oxide synthase (NOS) isoforms on glibenclamide-induced apoptosis in rat insulinoma cells. Our results showed that glibenclamide induces NO generation (measured as nitrite) that is accompanied with decrease of cell viability in a defined concentration of glibenclamide. The effects of glibenclamide on cell viability were partially inhibited after treatment with N(G)-nitro-L-arginine methyl ester (L-NAME), inhibitor more selective for constitutive nitric oxide synthase, and in the presence of D600--a blocker of voltage-gated L-type Ca(2+) channels inhibited Ca(2+) influx into beta cells, whereas aminoguanidine (AG), a preferential inhibitor of inducible NOS, was significantly less effective. Analysis of DNA fragmentation by electrophoresis and staining with Hoechest 33342 and propidium iodide showed that L-NAME, but not AG, prevented DNA fragmentation and decreased the number of cells with condensed and fragmented nuclei. It revealed that the effects of glibenclamide on apoptosis were partially inhibited by treatment with L-NAME. In conclusion, we have shown that NO production in glibenclamide treated cells may be involved in the induction of apoptotic cell death in pure beta cell line and it may be due to Ca(2+) dependent activation of constitutive NOS isoforms.
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Affiliation(s)
- Malek Moien Ansar
- Department of Clinical Biochemistry, Faculty of Medicine, Tehran University of Medical Sciences, Iran.
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Batenburg WW, Tom B, Schuijt MP, Danser AHJ. Angiotensin II type 2 receptor-mediated vasodilation. Focus on bradykinin, NO and endothelium-derived hyperpolarizing factor(s). Vascul Pharmacol 2005; 42:109-18. [PMID: 15792928 DOI: 10.1016/j.vph.2005.01.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Angiotensin (Ang) II type 1 (AT(1)) receptors account for the majority of the cardiovascular effects Ang II, including vasoconstriction and growth stimulation. Recent evidence, mainly obtained in animals, suggests that Ang II type 2 (AT(2)) receptors counteract some or all of these effects. This review summarizes the current knowledge on the vasodilator effects induced by AT(2) receptors in humans and animals, focussing not only on the mediators of this effect, but also on the modulatory role of age, gender, and endothelial function. It is concluded that AT(2) receptor-mediated vasodilation most likely depends on the bradykinin-bradykinin type 2 (B(2)) receptor-NO-cGMP pathway, although evidence for a direct link between AT(2) and B(2) receptors is currently lacking. If indeed B(2) receptors are involved, this would imply that, in addition to NO, also the wide range of non-NO 'endothelium-derived hyperpolarizing factors' (EDHFs) that is released following B(2) receptor activation (e.g., K(+), cytochrome P450 products from arachidonic acid, H(2)O(2) and S-nitrososothiols), could contribute to AT(2) receptor-induced vasodilation.
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Affiliation(s)
- Wendy W Batenburg
- Department of Pharmacology, room EE1418b, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
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Batenburg WW, de Vries R, Saxena PR, Danser AHJ. L-S-nitrosothiols: endothelium-derived hyperpolarizing factors in porcine coronary arteries? J Hypertens 2005; 22:1927-36. [PMID: 15361764 DOI: 10.1097/00004872-200410000-00015] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Bradykinin-induced, endothelium-derived hyperpolarizing factor (EDHF)-mediated responses depend on Ca-dependent K-channels (KCa) of small (SKCa) and intermediate (IKCa) conductance, inwardly rectifying K (KIR) channels and/or Na-K-ATPase. Here we investigated in porcine coronary arteries (PCAs) whether S-nitrosothiols can act as EDHF. METHODS Preconstricted PCAs were exposed to bradykinin, the NO donor S-nitroso-N-penicillamine (SNAP), or the S-nitrosothiols L-S-nitrosocysteine (L-SNC), D-SNC and L-S-nitrosoglutathione (L-SNG), with or without KCl, the NO scavenger hydroxocobalamin, the S-nitrosothiol-depleting agent p-hydroxymercurobenzoic acid (PHMBA) and/or inhibitors of NO synthase (L-NAME), guanylyl cyclase (ODQ), SKCa channels (apamin), KCa channels of large conductance (BKCa) (iberiotoxin), IKCa + BKCa channels (charybdotoxin), KIR channels (BaCl2) or Na-K-ATPase (ouabain). RESULTS All agonists concentration-dependently relaxed PCAs. L-NAME, charybdotoxin + apamin, KCl, and ouabain shifted the bradykinin concentration-response curve (CRC) approximately 10-fold to the right. BaCl2 did not exert additional effects on top of ouabain. Full blockade of bradykinin was obtained when combining L-NAME with charybdotoxin + apamin, KCl or ouabain + BaCl2. PHMBA reduced the maximum effect of bradykinin. Iberiotoxin + apamin, alone or on top of L-NAME, did not affect bradykinin, SNAP or L-SNC. ODQ and hydroxocobalamin shifted the SNAP, L-SNC, D-SNC, and L-SNG CRCs approximately 10-fold to the right, and, in combination, fully blocked SNAP-induced effects. Charybdotoxin + apamin shifted the L-SNC and L-SNG CRCs, but not the D-SNC or SNAP CRCs, approximately 5-fold to the right. KCl and ouabain (but not BaCl2) shifted the SNAP, L-SNC and L-SNG CRCs 5-10 fold to the right. CONCLUSIONS L-S-nitrosothiols activate SKCa + IKCa channels in a stereoselective manner, whereas NO activates Na-K-ATPase. Since S-nitrosothiols decompose to NO, stored L-S-nitrosothiols may mediate bradykinin-induced, EDHF-dependent relaxation.
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Schuijt MP, Tom B, de Vries R, Saxena PR, Sluiter W, van Kats JP, Danser AH. Superoxide does not mediate the acute vasoconstrictor effects of angiotensin II: a study in human and porcine arteries. J Hypertens 2004; 21:2335-44. [PMID: 14654755 DOI: 10.1097/00004872-200312000-00023] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To investigate whether superoxide mediates angiotensin (Ang) II-induced vasoconstriction. METHODS Human coronary arteries (HCAs), porcine femoral arteries (PFA) and porcine coronary arteries (PCAs) were mounted in organ baths and concentration-response curves to Ang II, the nitric oxide (NO) donor S-nitroso-N-acetylpenicillamine (SNAP) and the NAD(P)H oxidase substrate NADH were constructed in the absence and presence of superoxide inhibiting and activating drugs. Extracellular superoxide was measured using cytochrome c reduction. RESULTS Ang II constricted both HCAs and PFAs. In HCAs, the NAD(P)H inhibitors diphenyleneiodonium (DPI) and apocynin, and the xanthine oxidase (XO) inhibitor allopurinol, but not the superoxide dismutase (SOD) mimetic tempol or the SOD inhibitor diethyldithiocarbamate (DETCA), reduced this constriction. Catalase potentiated Ang II in HCAs, indicating a vasodilator role for H2O2. DPI, tempol and SOD did not affect Ang II in PFAs. DPI, apocynin and allopurinol relaxed preconstricted HCAs. Although the relaxant effects of the NO donor SNAP in PCAs was reduced by DETCA, indicating that superoxide-induced constrictions depend on NO inactivation, the apocynin-induced relaxations were NO independent. Moreover, NADH relaxed all vessels, and this effect was blocked by KCl but not DPI or NO removal. Xanthine plus XO also relaxed HCAs and PCAs. Incubation of human or porcine arteries with Ang II or NADH did not result in detectable increases of extracellular superoxide within 1 h. CONCLUSIONS Acute vasoconstriction by Ang II is not mediated via superoxide generated through NAD(P)H oxidase and/or XO activation. Such activation, if occurring, rather results in the generation of the vasodilator H2O2.
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Affiliation(s)
- Martin P Schuijt
- Department of Pharmacology, Erasmus MC, Rotterdam, The Netherlands
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Batenburg WW, Garrelds IM, Bernasconi CC, Juillerat-Jeanneret L, van Kats JP, Saxena PR, Danser AHJ. Angiotensin II type 2 receptor-mediated vasodilation in human coronary microarteries. Circulation 2004; 109:2296-301. [PMID: 15117835 DOI: 10.1161/01.cir.0000128696.12245.57] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Angiotensin (Ang) II type 2 (AT2) receptor stimulation results in coronary vasodilation in the rat heart. In contrast, AT2 receptor-mediated vasodilation could not be observed in large human coronary arteries. We studied Ang II-induced vasodilation of human coronary microarteries (HCMAs). METHODS AND RESULTS HCMAs (diameter, 160 to 500 microm) were obtained from 49 heart valve donors (age, 3 to 65 years). Ang II constricted HCMAs, mounted in Mulvany myographs, in a concentration-dependent manner (pEC50, 8.6+/-0.2; maximal effect [E(max)], 79+/-13% of the contraction to 100 mmol/L K+). The Ang II type 1 receptor antagonist irbesartan prevented this vasoconstriction, whereas the AT2 receptor antagonist PD123319 increased E(max) to 97+/-14% (P<0.05). The increase in E(max) was larger in older donors (correlation DeltaE(max) versus age, r=0.47, P<0.05). The PD123319-induced potentiation was not observed in the presence of the NO synthase inhibitor L-NAME, the bradykinin type 2 (B2) receptor antagonist Hoe140, or after removal of the endothelium. Ang II relaxed U46619-preconstricted HCMAs in the presence of irbesartan by maximally 49+/-16%, and PD123319 prevented this relaxation. Finally, radioligand binding studies and reverse transcription-polymerase chain reaction confirmed the expression of AT2 receptors in HCMAs. CONCLUSIONS AT2 receptor-mediated vasodilation in the human heart appears to be limited to coronary microarteries and is mediated by B2 receptors and NO. Most likely, AT2 receptors are located on endothelial cells, and their contribution increases with age.
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MESH Headings
- Adolescent
- Adult
- Aged
- Angiotensin II/pharmacology
- Angiotensin II Type 2 Receptor Blockers
- Biphenyl Compounds/pharmacology
- Child
- Child, Preschool
- Coronary Circulation/drug effects
- Coronary Vessels/drug effects
- Coronary Vessels/physiology
- Cyclic GMP/metabolism
- Female
- Humans
- Imidazoles/pharmacology
- Irbesartan
- Male
- Microcirculation/drug effects
- Middle Aged
- NG-Nitroarginine Methyl Ester/pharmacology
- Nitric Oxide/physiology
- Pyridines/pharmacology
- RNA, Messenger/biosynthesis
- Radioligand Assay
- Receptor, Angiotensin, Type 1/biosynthesis
- Receptor, Angiotensin, Type 1/drug effects
- Receptor, Angiotensin, Type 1/genetics
- Receptor, Angiotensin, Type 2/drug effects
- Receptor, Angiotensin, Type 2/genetics
- Receptor, Angiotensin, Type 2/physiology
- Receptor, Bradykinin B2/physiology
- Tetrazoles/pharmacology
- Vasodilation/drug effects
- Vasodilation/physiology
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Batenburg WW, Popp R, Fleming I, Vries RD, Garrelds IM, Saxena PR, Danser AHJ. Bradykinin-induced relaxation of coronary microarteries: S-nitrosothiols as EDHF? Br J Pharmacol 2004; 142:125-35. [PMID: 15066907 PMCID: PMC1574930 DOI: 10.1038/sj.bjp.0705747] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
1. To investigate whether S-nitrosothiols, in addition to NO, mediate bradykinin-induced vasorelaxation, porcine coronary microarteries (PCMAs) were mounted in myographs. 2. Following preconstriction, concentration-response curves (CRCs) were constructed to bradykinin, the NO donors S-nitroso-N-penicillamine (SNAP) and diethylamine NONOate (DEA-NONOate) and the S-nitrosothiols L-S-nitrosocysteine (L-SNC) and D-SNC. All agonists relaxed PCMAs. L-SNC was approximately 5-fold more potent than D-SNC. 3. The guanylyl cyclase inhibitor ODQ and the NO scavenger hydroxocobalamin induced a larger shift of the bradykinin CRC than the NO synthase inhibitor L-NAME, although all three inhibitors equally suppressed bradykinin-induced cGMP responses. 4. Complete blockade of bradykinin-induced relaxation was obtained with L-NAME in the presence of the large- and intermediate-conductance Ca(2+)-activated K(+)-channel (BK(Ca), IK(Ca)) blocker charybdotoxin and the small-conductance Ca(2+)-activated K(+)-channel (SK(Ca)) channel blocker apamin, but not in the presence of L-NAME, apamin and the BK(Ca) channel blocker iberiotoxin. 5. Inhibitors of cytochrome P450 epoxygenase, cyclooxygenase, voltage-dependent K(+) channels and ATP-sensitive K(+) channels did not affect bradykinin-induced relaxation. 6. SNAP-, DEA-NONOate- and D-SNC-induced relaxations were mediated entirely by the NO-guanylyl cyclase pathway. L-SNC-induced relaxations were partially blocked by charybdotoxin+apamin, but not by iberiotoxin+apamin, and this blockade was abolished following endothelium removal. ODQ, but not hydroxocobalamin, prevented L-SNC-induced increases in cGMP, and both drugs shifted the L-SNC CRC 5-10-fold to the right. 7. L-SNC hyperpolarized intact and endothelium-denuded coronary arteries. 8. Our results support the concept that bradykinin-induced relaxation is mediated via de novo synthesized NO and a non-NO, endothelium-derived hyperpolarizing factor (EDHF). S-nitrosothiols, via stereoselective activation of endothelial IK(Ca) and SK(Ca) channels, and through direct effects on smooth muscle cells, may function as an EDHF in porcine coronary microarteries.
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Affiliation(s)
| | - Rüdiger Popp
- Institut für Kardiovaskuläre Physiologie, Klinikum der J.W. Goethe-Universität, Frankfurt am Main, Germany
| | - Ingrid Fleming
- Institut für Kardiovaskuläre Physiologie, Klinikum der J.W. Goethe-Universität, Frankfurt am Main, Germany
| | - René de Vries
- Department of Pharmacology, Erasmus MC, Rotterdam, The Netherlands
| | | | - Pramod R Saxena
- Department of Pharmacology, Erasmus MC, Rotterdam, The Netherlands
| | - A H Jan Danser
- Department of Pharmacology, Erasmus MC, Rotterdam, The Netherlands
- Author for correspondence:
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Batenburg WW, Garrelds IM, van Kats JP, Saxena PR, Danser AHJ. Mediators of bradykinin-induced vasorelaxation in human coronary microarteries. Hypertension 2003; 43:488-92. [PMID: 14691197 DOI: 10.1161/01.hyp.0000110904.95771.26] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To investigate the mediators of bradykinin-induced vasorelaxation in human coronary microarteries (HCMAs), HCMAs (diameter approximately 300 microm) obtained from 42 heart valve donors (20 men and 22 women; age range, 3 to 65 years; mean age, 46 years) were mounted in Mulvany myographs. In the presence of the cyclooxygenase inhibitor indomethacin, bradykinin relaxed preconstricted HCMAs in a concentration-dependent manner. N(G)-nitro-L-arginine methyl ester and ODQ (inhibitors of nitric oxide [NO] synthase and guanylyl cyclase, respectively) and the NO scavenger hydroxocobalamin, either alone or in combination, shifted the bradykinin concentration-response curve to the right. Removal of H2O2 (with catalase), inhibition of cytochrome P450 epoxygenase (with sulfaphenazole or clotrimazole) or gap junctions (with 18alpha-glycyrrhetinic acid or carbenoxolone), and blockade of large- (BK(Ca)) and small- (SK(Ca)) conductance Ca2+-dependent K+ channels (with iberiotoxin and apamin), either alone or in addition to hydroxocobalamin, did not affect bradykinin. In contrast, complete blockade of bradykinin-induced relaxation was obtained when we combined the nonselective BK(Ca) and intermediate-conductance (IK(Ca)) Ca2+-dependent K+ channel blocker charybdotoxin and apamin with hydroxocobalamin. Charybdotoxin plus apamin alone were without effect. Inhibition of inwardly rectifying K+ channels (K(IR)) and Na+/K+-ATPase (with BaCl2 and ouabain, respectively) shifted the bradykinin concentration-response curve 10-fold to the right but did not exert an additional effect in the presence of hydroxocobalamin. In conclusion, bradykinin-induced relaxation in HCMAs depends on (1) the activation of guanylyl cyclase, K(IR), and Na(+)/K(+)-ATPase by NO and (2) IK(Ca) and SK(Ca) channels. The latter are activated by a factor other than NO. This factor is not a cytochrome P450 epoxygenase product or H2O2, nor does it depend on gap junctions or BK(Ca) channels.
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Affiliation(s)
- Wendy W Batenburg
- Department of Pharmacology, Erasmus Medical Center, Rotterdam, The Netherlands
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Tom B, Dendorfer A, Danser AHJ. Bradykinin, angiotensin-(1-7), and ACE inhibitors: how do they interact? Int J Biochem Cell Biol 2003; 35:792-801. [PMID: 12676166 DOI: 10.1016/s1357-2725(02)00273-x] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The beneficial effect of ACE inhibitors in hypertension and heart failure may relate, at least in part, to their capacity to interfere with bradykinin metabolism. In addition, recent studies have provided evidence for bradykinin-potentiating effects of ACE inhibitors that are independent of bradykinin hydrolysis, i.e. ACE-bradykinin type 2 (B(2)) receptor 'cross-talk', resulting in B(2) receptor upregulation and/or more efficient activation of signal transduction pathways, as well as direct activation of bradykinin type 1 receptors by ACE inhibitors. This review critically reviews the current evidence for hydrolysis-independent bradykinin potentiation by ACE inhibitors, evaluating not only the many studies that have been performed with ACE-resistant bradykinin analogues, but also paying attention to angiotensin-(1-7), a metabolite of both angiotensin I and II, that could act as an endogenous ACE inhibitor. The levels of angiotensin-(1-7) are increased during ACE inhibition, and most studies suggest that its hypotensive effects are mediated in a bradykinin-dependent manner.
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Affiliation(s)
- Beril Tom
- Department of Pharmacology, Room EE1418b, Erasmus Medical Centre, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
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Abstract
The concept of local renin-angiotensin systems has been introduced almost 20 years ago to explain the beneficial blood pressure-independent effects of ACE inhibitors and AT(1) receptor antagonists in cardiovascular diseases. In the past decade, research has focussed on the local effects of angiotensin II rather than on the mechanism(s) of its local generation. This review addresses several of the unanswered questions with regard to tissue angiotensin II generation, focussing in particular on the heart and vascular wall: (1) what is the origin of the renin that is required to generate angiotensin II locally, (2) where does tissue angiotensin generation occur (intra- versus extracellular), (3) what is the importance of alternative (non-renin, non-ACE) angiotensin-generating enzymes, (4) do ACE inhibitors and AT(1) receptor antagonists exert local effects that are renin-angiotensin system independent (thereby incorrectly leading to the conclusion that they interfere with the local generation or effects of angiotensin II), and (5) to what degree do differences in tissue angiotensin generation underlie the association between cardiovascular diseases and renin-angiotensin system gene polymorphisms?
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Affiliation(s)
- A H Jan Danser
- Department of Pharmacology, room EE1418b, Erasmus Medical Centre, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands.
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Thorsgaard M, Lopez V, Buus NH, Simonsen U. Different modulation by Ca2+-activated K+ channel blockers and herbimycin of acetylcholine- and flow-evoked vasodilatation in rat mesenteric small arteries. Br J Pharmacol 2003; 138:1562-70. [PMID: 12721112 PMCID: PMC1573811 DOI: 10.1038/sj.bjp.0705214] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. The present study addressed whether endothelium-dependent vasodilatation evoked by acetylcholine and flow are mediated by the same mechanisms in isolated rat mesenteric small arteries, suspended in a pressure myograph for the measurement of internal diameter. 2. In pressurized arterial segments contracted with U46619 in the presence of indomethacin, shear stress generated by the flow evoked relaxation. Thus, in endothelium-intact segments low (5.1+/-0.6 dyn cm(-2)) and high (19+/-2 dyn cm(-2)) shear stress evoked vasodilatations that were reduced by, respectively, 68+/-11 and 68+/-8% (P<0.05, n=7) by endothelial cell removal. Acetylcholine (0.01-1 microM) evoked concentration-dependent vasodilatation that was abolished by endothelial cell removal. 3. Incubation with indomethacin alone did not change acetylcholine and shear stress-evoked vasodilatation, while the combination of indomethacin with the nitric oxide (NO) synthase inhibitor, N(G),N(G)-asymmetric dimethyl-L-arginine (ADMA 1 mM), reduced low and high shear stress-evoked vasodilatation with, respectively, 52+/-15 and 58+/-10% (P<0.05, n=9), but it did not change acetylcholine-evoked vasodilatation. 4. Inhibition of Ca(2+)-activated K(+) channels with a combination of apamin (0.5 microM) and charybdotoxin (ChTX) (0.1 microM) did not change shear stress- and acetylcholine-evoked vasodilatation. In the presence of indomethacin and ADMA, the combination of apamin (0.5 microM) and ChTx (0.1 microM) increased contraction induced by U46619, but these blockers did not change the vasodilatation evoked by shear stress. In contrast, acetylcholine-evoked vasodilatation was abolished by the combination of apamin and charybdotoxin. 5. In the presence of indomethacin, the tyrosine kinase inhibitor, herbimycin A (1 microM), inhibited low and high shear stress-evoked vasodilatation with, respectively, 32+/-12 and 68+/-14% (P<0.05, n=8), but it did not change vasodilatation induced by acetylcholine. In the presence of indomethacin and ADMA, herbimycin A neither changed shear stress nor acetylcholine-evoked vasodilatation. 6. The present study suggests that Ca(2+)-activated K(+) channels sensitive for the combination of apamin and ChTx are involved in acetylcholine-evoked, mainly non-NO nonprostanoid factor-mediated, vasodilatation, while an Src tyrosine kinase plays a role for flow-evoked NO-mediated vasodilatation in rat mesenteric small arteries.
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Affiliation(s)
- Michael Thorsgaard
- Department of Pharmacology, University of Aarhus, 8000 Aarhus C, Denmark
| | - Vanesa Lopez
- Department of Pharmacology, University of Aarhus, 8000 Aarhus C, Denmark
| | - Niels H Buus
- Department of Pharmacology, University of Aarhus, 8000 Aarhus C, Denmark
| | - Ulf Simonsen
- Department of Pharmacology, University of Aarhus, 8000 Aarhus C, Denmark
- Author for correspondence:
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Liuba P, Pesonen E, Paakkari I, Batra S, Forslid A, Kovanen P, Pentikäinen M, Persson K, Sandström S. Acute Chlamydia pneumoniae infection causes coronary endothelial dysfunction in pigs. Atherosclerosis 2003; 167:215-22. [PMID: 12818403 DOI: 10.1016/s0021-9150(03)00019-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Coronary endothelial dysfunction contributes to the pathogenesis of acute coronary syndromes (ACSs). Acute Chlamydia pneumoniae infection has been epidemiologically associated with ACS. In this study, we investigated whether acute C. pneumoniae infection could alter the endothelial vasomotor function of porcine coronary vessels. METHODS AND RESULTS Twenty pigs, 7-9 kg in weight, were inoculated intratracheally with C. pneumoniae (n=12) or saline (n=8), and investigated at 3 days (five infected/four non-infected) and 2 weeks (5+2 infected/four non-infected) after inoculation. The endothelium-dependent reactivity of coronary microcirculation was assessed at both time points by measuring peak coronary flow velocity (CFV) in response to bradykinin, before and after infusions with glutathione, an antioxidant, and L-arginine, a substrate for nitric oxide synthase (NOS). CFV after bradykinin was significantly decreased in infected animals at both time points. At 2 weeks, both glutathione and L-arginine significantly improved CFV after bradykinin. CFV after sodium nitroprusside (SNP) was similar in both groups. At 3 days, the relaxation responses of bradykinin-induced pre-contracted left anterior descending (LAD) coronary rings to bradykinin were significantly less in infected animals. N(G)-nitro-L-arginine-methyl-ester, an NOS inhibitor, had significantly greater inhibitory effect on bradykinin-induced relaxation in infected animals. Plasma nitrate-nitrite and fibrinogen, and NOS activity from LAD coronary samples were significantly increased in infected animals. CONCLUSION Acute C. pneumoniae infection causes endothelial dysfunction of both resistance and epicardial coronary vessels, and favours a pro-coagulant status. These effects could in part account for the epidemiologically suggested association between acute infection and ACS.
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Affiliation(s)
- Petru Liuba
- Department of Pediatric Cardiology, Lund University Hospital, Lund 22185, Sweden.
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Abstract
Nitric oxide (NO) is involved in a large number of cellular processes and dysfunctions in NO production have been implicated in many different disease states. In the vasculature NO is released by endothelial cells where it modulates the underlying smooth muscle to regulate vascular tone. Due to the unique chemistry of NO, such as its reactive and free radical nature, it can interact with many different cellular constituents such as thiols and transition metal ions, which determine its cellular actions. In this review we also discuss many of the useful pharmacological tools that have been developed and used extensively to establish the involvement of NO in endothelium-derived relaxations. In addition, the recent literature identifying a potential source of NO in endothelial cells, which is not directly derived from endothelial nitric oxide synthase is examined. Finally, the photorelaxation phenomena, which mediates the release of NO from a vascular smooth muscle NO store, is discussed.
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Affiliation(s)
- Karen L Andrews
- Smooth Muscle Research Group, Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Calgary, Hospital Drive NW, Calgary, AB, Canada
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Tracey A, Bunton D, Irvine J, MacDonald A, Shaw AM. Relaxation to bradykinin in bovine pulmonary supernumerary arteries can be mediated by both a nitric oxide-dependent and -independent mechanism. Br J Pharmacol 2002; 137:538-44. [PMID: 12359636 PMCID: PMC1573515 DOI: 10.1038/sj.bjp.0704890] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
1. The aim of the present study was to determine the relative contribution of prostanoids, nitric oxide and K(+) channels in the bradykinin-induced relaxation of bovine pulmonary supernumerary arteries. 2. In endothelium-intact, but not denuded rings, bradykinin produced a concentration-dependent relaxation (pEC(50), 9.6+/-0.1), which was unaffected by the cyclo-oxygenase inhibitor indomethacin. The nitric oxide scavenger hydroxocobalamin (200 micro M, pEC(50), 8.5+/-0.2) and the nitric oxide synthase inhibitor L-NAME (100 micro M, pEC(50), 8.9+/-0.1) and the combination of L-NAME and hydroxocobalamin (pEC(50), 8.1+/-0.2) produced rightward shifts in the bradykinin concentration response curve. 3. The guanylyl cyclase inhibitor ODQ (10 micro M, pEC(50), 9.6+/-0.4) did not affect the response to bradykinin. 4. Elevating the extracellular [K(+)] to 30 mM did not affect the response to bradykinin but abolished the response when ODQ or L-NAME was present. 5. The K(+) channel blocker apamin (100 nM), combined with charybdotoxin (100 nM), produced a small reduction in the maximum response to bradykinin but they abolished the response to bradykinin when ODQ, L-NAME or hydroxocobalamin were present. Apamin (100 nM) combined with iberiotoxin (100 nM) also reduced the response to bradykinin in the presence of hydroxocobalamin or L-NAME. 6. The concentration response curve for sodium nitroprusside-induced relaxation was abolished by ODQ (10 micro M) and shifted to the right by apamin and charybdotoxin. 7. These studies suggest that in bovine pulmonary supernumerary arteries bradykinin can stimulate the formation of nitric oxide and activate an EDHF-like mechanism and that either of these pathways alone can mediate the bradykinin-induced relaxation. In addition nitric oxide, acting through guanylyl cyclase, can activate an apamin/charbydotoxin-sensitive K(+) channel in this tissue.
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Affiliation(s)
- A Tracey
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
| | - D Bunton
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
| | - J Irvine
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
| | - A MacDonald
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
| | - A M Shaw
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
- Author for correspondence:
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Tom B, Dendorfer A, Vries RD, Saxena PR, Jan Danser AH. Bradykinin potentiation by ACE inhibitors: a matter of metabolism. Br J Pharmacol 2002; 137:276-84. [PMID: 12208785 PMCID: PMC1573486 DOI: 10.1038/sj.bjp.0704862] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Studies in isolated cells overexpressing ACE and bradykinin type 2 (B(2)) receptors suggest that ACE inhibitors potentiate bradykinin by inhibiting B(2) receptor desensitization, via a mechanism involving protein kinase C (PKC) and phosphatases. Here we investigated, in intact porcine coronary arteries, endothelial ACE/B(2) receptor 'crosstalk' as well as bradykinin potentiation through neutral endopeptidase (NEP) inhibition. 2. NEP inhibition with phosphoramidon did not affect the bradykinin concentration-response curve (CRC), nor did combined NEP/ACE inhibition with omapatrilat exert a further leftward shift on top of the approximately 10 fold leftward shift of the bradykinin CRC observed with ACE inhibition alone. 3. In arteries that, following repeated exposure to 0.1 microM bradykinin, no longer responded to bradykinin ('desensitized' arteries), the ACE inhibitors quinaprilat and angiotensin-(1-7) both induced complete relaxation, without affecting the organ bath fluid levels of bradykinin. This phenomenon was unaffected by inhibition of PKC or phosphatases (with calphostin C and okadaic acid, respectively). 4. When using bradykinin analogues that were either completely or largely ACE-resistant ([Phe(8)psi(CH(2)-NH)Arg(9)]-bradykinin and [deltaPhe(5)]-bradykinin, respectively), the ACE inhibitor-induced shift of the bradykinin CRC was absent, and its ability to reverse desensitization was absent or significantly reduced, respectively. Caveolar disruption with filipin did not affect the quinaprilat-induced effects. Filipin did however reduce the bradykinin-induced relaxation by approximately 25-30%, thereby confirming that B(2) receptor-endothelial NO synthase (eNOS) interaction occurs in caveolae. 5. In conclusion, in porcine arteries, in contrast to transfected cells, bradykinin potentiation by ACE inhibitors is a metabolic process, that can only be explained on the basis of ACE-B(2) receptor co-localization on the endothelial cell membrane. NEP does not appear to affect the bradykinin levels in close proximity to B(2) receptors, and the ACE inhibitor-induced bradykinin potentiation precedes B(2) receptor coupling to eNOS in caveolae.
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Affiliation(s)
- Beril Tom
- Department of Pharmacology, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Andreas Dendorfer
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - René de Vries
- Department of Pharmacology, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Pramod R Saxena
- Department of Pharmacology, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - A H Jan Danser
- Department of Pharmacology, Erasmus Medical Centre, Rotterdam, The Netherlands
- Author for correspondence:
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Kimura S, Tsuji H, Nishimura H, Kato H, Ukimura N, Yano S, Kunieda Y, Kawano H, Nakagawa K, Nakagawa M. Bradykinin enhances in vitro procoagulant and antifibrinolytic properties of rat vascular endothelial cells. Thromb Res 2002; 106:41-50. [PMID: 12165288 DOI: 10.1016/s0049-3848(02)00070-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Bradykinin (BK) is a biologically active peptides that exerts a broad spectrum of pathophysiological effects mainly by producing nitric oxide (NO) and prostacyclin from vascular endothelial cells. A direct effect of BK on vascular endothelial cells regarding the expression of the regulatory proteins of coagulation and fibrinolysis has not been fully elucidated. MATERIALS AND METHODS The effects of BK on the expression of tissue factor (TF), tissue factor pathway inhibitor (TFPI), plasminogen activator inhibitor-1 (PAI-1), and tissue-type plasminogen activator (TPA) in cultured rat aortic endothelial cells (RAECs) were respectively evaluated by Northern blot and chromogenic assay or enzyme-linked immunosorbent assay (ELISA). RESULTS BK significantly increased the expression of TF and PAI-1 in both mRNA and protein levels, but it did not affect the expression of TFPI. Although BK tended to increase TPA mRNA expression, the observed increase was not statistically significant. Those effects are considered to be mediated by B(2) receptor, because B(2) receptor antagonist (Hoe 140) suppressed those mRNA inductions by BK. Furthermore, since those mRNA inductions by BK were enhanced by nitro-L-arginine-methyl ester (L-NAME) and attenuated by L-arginine (L-Arg), NO was speculated to negatively contribute to the expressions of TF and PAI-1. CONCLUSION BK was indicated to modify the property of vascular endothelial cells to be procoagulant and antifibrinolytic. Those effects of BK were considered to be the net of its direct effect and the effect negatively mediated by NO.
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Affiliation(s)
- Shinzo Kimura
- Second Department of Medicine, Kyoto Prefectural University of Medicine, 465 Kawaramachi-Hirokoji, Kamigyo-ku, 602-8566, Kyoto, Japan
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Fulep EE, Vedernikov YP, Saade GR, Garfield RE. The role of endothelium-derived hyperpolarizing factor in the regulation of the uterine circulation in pregnant rats. Am J Obstet Gynecol 2001; 185:638-42. [PMID: 11568792 DOI: 10.1067/mob.2001.117665] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The purpose of this study was to determine whether endothelium-derived hyperpolarizing factor regulates rat uterine circulation in pregnant rats. STUDY DESIGN Intact isolated uterine vascular beds from late pregnant rats were perfused in situ with Krebs buffer that contained dextran, indomethacin, N-nitro-L-arginine methyl ester, and phenylephrine. Endothelium-derived hyperpolarizing factor-induced decreases in perfusion pressure in response to acetylcholine were analyzed. RESULTS The decrease in perfusion pressure induced by endothelium-derived hyperpolarizing factor was significantly attenuated by 4-aminopyridine and was abolished by a combination of 4-aminopyridine and tetraethylammonium. Endothelium-derived hyperpolarizing factor-induced decrease in perfusion pressure was abolished by potassium chloride and attenuated by miconazole, but not linoleyl hydroxamic acid. Endothelium-derived hyperpolarizing factor-induced decrease in perfusion pressure persisted after perfusion with solutions that contained 2 inhibitors of nitric oxide synthase and a scavenger of nitric oxide. Nitric oxide exerted negative feedback on the endothelium-derived hyperpolarizing factor effects. CONCLUSION In the pregnant rat uterine vascular beds, endothelium-derived hyperpolarizing factor release is activated by a delayed rectifier type of voltage-sensitive potassium channel. Endothelium-derived hyperpolarizing factor does not seem to be related to nitric oxide or to products of lipoxygenase or cytochrome p450 mono-oxygenase pathways of arachidonic acid metabolism.
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Affiliation(s)
- E E Fulep
- Department of Obstetrics and Gynecology, Reproductive Sciences, University of Texas Medical Branch, Galveston, USA
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Tom B, de Vries R, Saxena PR, Danser AH. Negative inotropic effect of bradykinin in porcine isolated atrial trabeculae: role of nitric oxide. J Hypertens 2001; 19:1289-93. [PMID: 11446719 DOI: 10.1097/00004872-200107000-00014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To investigate whether bradykinin affects cardiac contractility independently of its effects on coronary flow and noradrenaline release, and whether such inotropic effects, if present, are mediated via nitric oxide (NO). METHODS Right atrial trabeculae were obtained from 35 pigs, suspended in organ baths and attached to isometric transducers. Resting tension was set at approximately 750 mg and tissues were paced at 1.5 Hz. Tissue viability was checked by constructing a concentration response curve (CRC) to noradrenaline. Next, CRCs were constructed to bradykinin, either under baseline conditions or after pre-stimulation with the positive inotropic agent forskolin (1 or 10 micromol/l), in the absence or presence of the bradykinin type 2 (B2) receptor antagonist D-Arg [Hyp3-Thi5, d-Tic7, Oic8]-bradykinin (Hoe 140) (1 micromol/l), the NO synthase inhibitor Nomega-nitro-L-arginine methyl ester (L-NAME) (100 micromol/l) and/or the NO scavenger hydroxocobalamin (200 micromol/l). RESULTS Bradykinin exerted a negative inotropic effect, both with and without forskolin pre-stimulation, reducing contractility by maximally 22 +/- 3.6% (mean +/- SEM) and 23 +/- 3.6%, respectively (pEC50 8.37 +/- 0.23 and 8.62 +/- 0.22, respectively). L-NAME reduced this effect in pre-stimulated, but not in unstimulated, trabeculae. Hoe 140 and hydroxocobalamin fully blocked the inotropic effect of bradykinin. CONCLUSIONS Bradykinin induces a modest negative inotropic effect in porcine atrial trabeculae that is mediated via B2 receptors and NO. The inconsistent results obtained with L-NAME suggest that it depends on NO synthesized de novo and/or NO from storage sites.
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Affiliation(s)
- B Tom
- Department of Pharmacology, Erasmus University Rotterdam, The Netherlands
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Tom B, de Vries R, Saxena PR, Danser AH. Bradykinin potentiation by angiotensin-(1-7) and ACE inhibitors correlates with ACE C- and N-domain blockade. Hypertension 2001; 38:95-9. [PMID: 11463767 DOI: 10.1161/01.hyp.38.1.95] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
ACE inhibitors block B(2) receptor desensitization, thereby potentiating bradykinin beyond blocking its hydrolysis. Angiotensin (Ang)-(1-7) also acts as an ACE inhibitor and, in addition, may stimulate bradykinin release via angiotensin II type 2 receptors. In this study we compared the bradykinin-potentiating effects of Ang-(1-7), quinaprilat, and captopril. Porcine coronary arteries, obtained from 32 pigs, were mounted in organ baths, preconstricted with prostaglandin F(2alpha), and exposed to quinaprilat, captopril, Ang-(1-7), and/or bradykinin. Bradykinin induced complete relaxation (pEC(50)=8.11+/-0.07, mean+/-SEM), whereas quinaprilat, captopril, and Ang-(1-7) alone were without effect. Quinaprilat shifted the bradykinin curve to the left in a biphasic manner: a 5-fold shift at concentrations that specifically block the C-domain (0.1 to 1 nmol/L) and a 10-fold shift at concentrations that block both domains. Captopril and Ang-(1-7) monophasically shifted the bradykinin curve to the left, by a factor of 10 and 5, respectively. A 5-fold shift was also observed when Ang-(1-7) was combined with 0.1 nmol/L quinaprilat. Repeated exposure of porcine coronary arteries to 0.1 micromol/L bradykinin induced B(2) receptor desensitization. The addition of 10 micromol/L quinaprilat or Ang-(1-7) to the bath, at a time when bradykinin alone was no longer able to induce relaxation, fully restored the relaxant effects of bradykinin. Angiotensin II type 1 or 2 receptor blockade did not affect any of the observed effects of Ang-(1-7). In conclusion, Ang-(1-7), like quinaprilat and captopril, potentiates bradykinin by acting as an ACE inhibitor. Bradykinin potentiation is maximal when both the ACE C- and N-terminal domains are inhibited. The inhibitory effects of Ang-(1-7) are limited to the ACE C-domain, raising the possibility that Ang-(1-7) synergistically increases the blood pressure-lowering effects of N-domain-specific ACE inhibitors.
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Affiliation(s)
- B Tom
- Department of Pharmacology, Erasmus University Rotterdam, The Netherlands
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