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The mKATP Channels and protein-kinase C Are Involved in the Cardioprotective Effects of Genistein on Estrogen-Deficient Rat Hearts Exposed to Ischemia/Reperfusion: Energetic Study. J Cardiovasc Pharmacol 2020; 75:460-474. [PMID: 32195757 DOI: 10.1097/fjc.0000000000000816] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Estrogenic deficiency is considered a risk of coronary disease in women. The phytoestrogen genistein could be a safe preventive strategy. The first aim of this work was to validate a model of cardiac stunning in which natural estrogenic deficiency rats, ie, adult young male (YM) and aged female (AgF), are compared with young female rats (YF). The second aim was to study whether the in vivo administration of genistein prevents the stunning in estrogenic deficiency rats. The third aim was to evaluate whether in our estrogenic deficiency model exists a synergy between genistein and estradiol. The fourth aim was to characterize the underlying mechanisms of genistein. Stunning was induced by ischemia/reperfusion (I/R) in isolated hearts inside a calorimeter. The left ventricular pressure (P) and total heat rate (Ht) were simultaneously measured, while diastolic contracture and muscle economy (P/Ht) were calculated. During R, P/Ht and P recovered less in AgF and YM than in YF rat hearts. Genistein through i.p. (GST-ip) improved P and P/Ht in AgF and YM, but not in YF. In YM, the cardioprotections of GST-ip and estradiol were synergistic. After ischemia, GST-ip increased SR Ca leak causing diastolic contracture. The GST-ip cardioprotection neither was affected by blockade of PI3K-Akt, NO synthases, or phosphatases, but it was sensitive to blockade of protein-kinase C and mKATP channels. Results suggest that (1) estrogenic deficiency worsens cardiac stunning, (2) GST-ip was more cardioprotective in estrogenic deficiency and synergistic with estradiol, and (3) cardioprotection of GST-ip depends on the protein-kinase C and mKATP channel pathway activation.
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2
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Knock GA. NADPH oxidase in the vasculature: Expression, regulation and signalling pathways; role in normal cardiovascular physiology and its dysregulation in hypertension. Free Radic Biol Med 2019; 145:385-427. [PMID: 31585207 DOI: 10.1016/j.freeradbiomed.2019.09.029] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/29/2019] [Accepted: 09/23/2019] [Indexed: 02/06/2023]
Abstract
The last 20-25 years have seen an explosion of interest in the role of NADPH oxidase (NOX) in cardiovascular function and disease. In vascular smooth muscle and endothelium, NOX generates reactive oxygen species (ROS) that act as second messengers, contributing to the control of normal vascular function. NOX activity is altered in response to a variety of stimuli, including G-protein coupled receptor agonists, growth-factors, perfusion pressure, flow and hypoxia. NOX-derived ROS are involved in smooth muscle constriction, endothelium-dependent relaxation and smooth muscle growth, proliferation and migration, thus contributing to the fine-tuning of blood flow, arterial wall thickness and vascular resistance. Through reversible oxidative modification of target proteins, ROS regulate the activity of protein tyrosine phosphatases, kinases, G proteins, ion channels, cytoskeletal proteins and transcription factors. There is now considerable, but somewhat contradictory evidence that NOX contributes to the pathogenesis of hypertension through oxidative stress. Specific NOX isoforms have been implicated in endothelial dysfunction, hyper-contractility and vascular remodelling in various animal models of hypertension, pulmonary hypertension and pulmonary arterial hypertension, but also have potential protective effects, particularly NOX4. This review explores the multiplicity of NOX function in the healthy vasculature and the evidence for and against targeting NOX for antihypertensive therapy.
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Affiliation(s)
- Greg A Knock
- Dpt. of Inflammation Biology, School of Immunology & Microbial Sciences, Faculty of Life Sciences & Medicine, King's College London, UK.
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Terada Y, Higashi N, Hidaka Y, Isomoto Y, Yayama K. Protein Tyrosine Phosphatase Inhibitor, Orthovanadate, Induces Contraction via Rho Kinase Activation in Mouse Thoracic Aortas. Biol Pharm Bull 2019; 42:877-885. [PMID: 31155587 DOI: 10.1248/bpb.b18-00708] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Orthovanadate (OVA), a protein tyrosine phosphatase inhibitor, induces contraction in endothelium-denuded mouse thoracic aortas. OVA-induced contraction was significantly (vs. control rings) suppressed by Rho kinase (Y-27632, 10 µM), extracellular signal-regulated kinase 1 and 2 (Erk1/2, FR180204, 10 µM), Erk1/2 kinase (MEK, PD98059, 10 µM), epidermal growth factor receptor (EGFR, AG1478, 10 µM), and Src inhibitors, and was partially suppressed by c-Jun N-terminal kinase (JNK, AS601245, 10 µM) and p38 (SB203580, 10 µM) inhibitors. However, a myosin light chain kinase inhibitor (ML-7, 10 µM) and a metalloproteinase inhibitor (TAPI-0, 10 µM) had no effect on OVA-induced contraction in mouse thoracic aortas. Phosphorylation of myosin phosphatase target subunit 1 (MYPT1) was abolished by inhibitors of Src, EGFR, MEK, Erk1/2, and Rho kinase, but not by inhibitors of JNK and p38. Erk1/2 phosphorylation by OVA was blocked by inhibitors of EGFR, Src, MEK, and Erk1/2, but not by Rho kinase inhibition. Src phosphorylation at Tyr-416 was abrogated by only Src inhibitor. EGFR phosphorylation at Tyr-1173 was suppressed by a Src inhibitor. These findings suggest that OVA induces contraction via activation of Src, EGFR, MEK, Erk1/2, and Rho kinase, leading to inactivation of myosin light chain phosphatase via MYPT1 phosphorylation.
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Affiliation(s)
- Yuka Terada
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
| | - Naoki Higashi
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
| | - Yuki Hidaka
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
| | - Yasumasa Isomoto
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
| | - Katsutoshi Yayama
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
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4
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DeLalio LJ, Billaud M, Ruddiman CA, Johnstone SR, Butcher JT, Wolpe AG, Jin X, Keller TCS, Keller AS, Rivière T, Good ME, Best AK, Lohman AW, Swayne LA, Penuela S, Thompson RJ, Lampe PD, Yeager M, Isakson BE. Constitutive SRC-mediated phosphorylation of pannexin 1 at tyrosine 198 occurs at the plasma membrane. J Biol Chem 2019; 294:6940-6956. [PMID: 30814251 DOI: 10.1074/jbc.ra118.006982] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/15/2019] [Indexed: 11/06/2022] Open
Abstract
Pannexin 1 (PANX1)-mediated ATP release in vascular smooth muscle coordinates α1-adrenergic receptor (α1-AR) vasoconstriction and blood pressure homeostasis. We recently identified amino acids 198-200 (YLK) on the PANX1 intracellular loop that are critical for α1-AR-mediated vasoconstriction and PANX1 channel function. We report herein that the YLK motif is contained within an SRC homology 2 domain and is directly phosphorylated by SRC proto-oncogene, nonreceptor tyrosine kinase (SRC) at Tyr198 We demonstrate that PANX1-mediated ATP release occurs independently of intracellular calcium but is sensitive to SRC family kinase (SFK) inhibition, suggestive of channel regulation by tyrosine phosphorylation. Using a PANX1 Tyr198-specific antibody, SFK inhibitors, SRC knockdown, temperature-dependent SRC cells, and kinase assays, we found that PANX1-mediated ATP release and vasoconstriction involves constitutive phosphorylation of PANX1 Tyr198 by SRC. We specifically detected SRC-mediated Tyr198 phosphorylation at the plasma membrane and observed that it is not enhanced or induced by α1-AR activation. Last, we show that PANX1 immunostaining is enriched in the smooth muscle layer of arteries from hypertensive humans and that Tyr198 phosphorylation is detectable in these samples, indicative of a role for membrane-associated PANX1 in small arteries of hypertensive humans. Our discovery adds insight into the regulation of PANX1 by post-translational modifications and connects a significant purinergic vasoconstriction pathway with a previously identified, yet unexplored, tyrosine kinase-based α1-AR constriction mechanism. This work implicates SRC-mediated PANX1 function in normal vascular hemodynamics and suggests that Tyr198-phosphorylated PANX1 is involved in hypertensive vascular pathology.
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Affiliation(s)
- Leon J DeLalio
- From the Robert M. Berne Cardiovascular Research Center.,Department of Pharmacology
| | - Marie Billaud
- the Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213
| | - Claire A Ruddiman
- From the Robert M. Berne Cardiovascular Research Center.,Department of Pharmacology
| | | | - Joshua T Butcher
- the Department of Physiology, Augusta University, Augusta, Georgia 30912
| | - Abigail G Wolpe
- From the Robert M. Berne Cardiovascular Research Center.,Department of Cell Biology, and
| | - Xueyao Jin
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
| | - T C Stevenson Keller
- From the Robert M. Berne Cardiovascular Research Center.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
| | - Alexander S Keller
- From the Robert M. Berne Cardiovascular Research Center.,Department of Pharmacology
| | - Thibaud Rivière
- the Department of Life and Health Sciences, University of Bordeaux, 33000 Bordeaux, France
| | | | - Angela K Best
- From the Robert M. Berne Cardiovascular Research Center
| | - Alexander W Lohman
- the Hotchkiss Brain Institute and.,Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Leigh Anne Swayne
- the Division of Medical Sciences, Centre for Biomedical Research, University of Victoria, Victoria, British Columbia V8P 5C2, Canada
| | - Silvia Penuela
- the Departments of Anatomy and Cell Biology and Oncology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario N6A 3K7, Canada, and
| | - Roger J Thompson
- the Hotchkiss Brain Institute and.,Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Paul D Lampe
- the Fred Hutchinson Cancer Research Center, Seattle, Washington 98109
| | - Mark Yeager
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
| | - Brant E Isakson
- From the Robert M. Berne Cardiovascular Research Center, .,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
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Panchal SK, Wanyonyi S, Brown L. Selenium, Vanadium, and Chromium as Micronutrients to Improve Metabolic Syndrome. Curr Hypertens Rep 2017; 19:10. [PMID: 28197835 DOI: 10.1007/s11906-017-0701-x] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Trace metals play an important role in the proper functioning of carbohydrate and lipid metabolism. Some of the trace metals are thus essential for maintaining homeostasis, while deficiency of these trace metals can cause disorders with metabolic and physiological imbalances. This article concentrates on three trace metals (selenium, vanadium, and chromium) that may play crucial roles in controlling blood glucose concentrations possibly through their insulin-mimetic effects. For these trace metals, the level of evidence available for their health effects as supplements is weak. Thus, their potential is not fully exploited for the target of metabolic syndrome, a constellation that increases the risk for cardiovascular disease and type 2 diabetes. Given that the prevalence of metabolic syndrome is increasing throughout the world, a simpler option of interventions with food supplemented with well-studied trace metals could serve as an answer to this problem. The oxidation state and coordination chemistry play crucial roles in defining the responses to these trace metals, so further research is warranted to understand fully their metabolic and cardiovascular effects in human metabolic syndrome.
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Affiliation(s)
- Sunil K Panchal
- Institute for Agriculture and the Environment, University of Southern Queensland, QLD, Toowoomba, 4350, Australia
| | - Stephen Wanyonyi
- Institute for Agriculture and the Environment, University of Southern Queensland, QLD, Toowoomba, 4350, Australia
| | - Lindsay Brown
- Institute for Agriculture and the Environment, University of Southern Queensland, QLD, Toowoomba, 4350, Australia.
- School of Health and Wellbeing, University of Southern Queensland, QLD, Toowoomba, 4350, Australia.
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Mironova GY, Avdonin PP, Goncharov NV, Jenkins RO, Avdonin PV. Inhibition of protein tyrosine phosphatases unmasks vasoconstriction and potentiates calcium signaling in rat aorta smooth muscle cells in response to an agonist of 5-HT2B receptors BW723C86. Biochem Biophys Res Commun 2017; 483:700-705. [DOI: 10.1016/j.bbrc.2016.12.079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 12/12/2016] [Indexed: 11/25/2022]
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7
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Colareda GA, Ragone MI, Consolini AE. Sex differences in the mechano-energetic effects of genistein on stunned rat and guinea pig hearts. Clin Exp Pharmacol Physiol 2015; 43:102-15. [DOI: 10.1111/1440-1681.12500] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 09/12/2015] [Accepted: 10/02/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Germán A Colareda
- Experimental Pharmacology Group (GFEYEC); Department of Biological Sciences, School of Exactas Sciences; National University of La Plata; La Plata Argentina
| | - María I Ragone
- Experimental Pharmacology Group (GFEYEC); Department of Biological Sciences, School of Exactas Sciences; National University of La Plata; La Plata Argentina
- National Council of Scientific and Technical Research (CONICET); La Plata Argentina
| | - Alicia E Consolini
- Experimental Pharmacology Group (GFEYEC); Department of Biological Sciences, School of Exactas Sciences; National University of La Plata; La Plata Argentina
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8
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Mills RD, Mita M, Walsh MP. A role for the Ca2+-dependent tyrosine kinase Pyk2 in tonic depolarization-induced vascular smooth muscle contraction. J Muscle Res Cell Motil 2015; 36:479-89. [DOI: 10.1007/s10974-015-9416-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 06/27/2015] [Indexed: 10/24/2022]
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9
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Ito K, Matsuzaki M, Sasahara T, Shin M, Yayama K. Orthovanadate-Induced Vasoconstriction of Rat Mesenteric Arteries Is Mediated by Rho Kinase-Dependent Inhibition of Myosin Light Chain Phosphatase. Biol Pharm Bull 2015; 38:1809-16. [DOI: 10.1248/bpb.b15-00587] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Kazuya Ito
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
| | - Mai Matsuzaki
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
| | - Tomoya Sasahara
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
| | - Mariko Shin
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
| | - Katsutoshi Yayama
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University
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10
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Yayama K, Sasahara T, Ohba H, Funasaka A, Okamoto H. Orthovanadate-induced vasocontraction is mediated by the activation of Rho-kinase through Src-dependent transactivation of epidermal growth factor receptor. Pharmacol Res Perspect 2014; 2:e00039. [PMID: 25505586 PMCID: PMC4184709 DOI: 10.1002/prp2.39] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 02/25/2014] [Accepted: 02/28/2014] [Indexed: 01/26/2023] Open
Abstract
Orthovanadate (OVA), a protein tyrosine phosphatase (PTPase) inhibitor, exerts contractile effects on smooth muscle in a Rho-kinase-dependent manner, but the precise mechanisms are not elucidated. The aim of this study was to determine the potential roles of Src and epidermal growth factor receptor (EGFR) in the OVA-induced contraction of rat aortas and the phosphorylation of myosin phosphatase target subunit 1 (MYPT1; an index of Rho-kinase activity) in vascular smooth muscle cells (VSMCs). Aortic contraction by OVA was significantly blocked not only by Rho kinase inhibitors Y-27632 [R-[+]-trans-N-[4-pyridyl]-4-[1-aminoethyl]-cyclohexanecarboxamide] and hydroxyfasudil [1-(1-hydroxy-5-isoquinolinesulfonyl)homopiperazine] but also by Src inhibitors PP2 [4-amino-3-(4-chlorophenyl)-1-(t-butyl)-1H-pyrazolo[3,4-d]pyrimidine] and Src inhibitor No. 5 [4-(3′-methoxy-6′-chloro-anilino)-6-methoxy-7(morpholino-3-propoxy)-quinazoline], and the EGFR inhibitors AG1478 [4-(3-chloroanilino)-6,7-dimethoxyquinazoline] and EGFR inhibitor 1 [cyclopropanecarboxylic acid-(3-(6-(3-trifluoromethyl-phenylamino)-pyrimidin-4-ylamino)-phenyl)-amide]. OVA induced rapid increases in the phosphorylation of MYPT1 (Thr-853), Src (Tyr-416), and EGFR (Tyr-1173) in VSMCs, and Src inhibitors abolished these effects. OVA-induced Src phosphorylation was abrogated by Src inhibitors, but not affected by inhibitors of EGFR and Rho-kinase. Inhibitors of Src and EGFR, but not Rho-kinase, also blocked OVA-induced EGFR phosphorylation. Furthermore, a metalloproteinase inhibitor TAPI-0 [N-(R)-[2-(hydroxyaminocarbonyl) methyl]-4-methylpentanoyl-l-naphthylalanyl-l-alanine amide] and an inhibitor of heparin-binding EGF (CRM 197) not only abrogated the OVA-induced aortic contraction, but also OVA-induced EGFR and MYPT1 phosphorylation, suggesting the involvement of EGFR transactivation. OVA also induced EGFR phosphorylation at Tyr-845, one of residues phosphorylated by Src. These results suggest that OVA-induced vasocontraction is mediated by the Rho-kinase-dependent inactivation of myosin light-chain phosphatase via signaling downstream of Src-induced transactivation of EGFR.
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Affiliation(s)
- Katsutoshi Yayama
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University Minatojima 1-1-3, Chuo-ku, Kobe, 650-8586, Japan
| | - Tomoya Sasahara
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University Minatojima 1-1-3, Chuo-ku, Kobe, 650-8586, Japan
| | - Hisaaki Ohba
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University Minatojima 1-1-3, Chuo-ku, Kobe, 650-8586, Japan
| | - Ayaka Funasaka
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University Minatojima 1-1-3, Chuo-ku, Kobe, 650-8586, Japan
| | - Hiroshi Okamoto
- Laboratory of Cardiovascular Pharmacology, Department of Biopharmaceutical Sciences, Kobe Gakuin University Minatojima 1-1-3, Chuo-ku, Kobe, 650-8586, Japan
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11
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Mita M, Tanaka H, Yanagihara H, Nakagawa JI, Hishinuma S, Sutherland C, Walsh MP, Shoji M. Membrane depolarization-induced RhoA/Rho-associated kinase activation and sustained contraction of rat caudal arterial smooth muscle involves genistein-sensitive tyrosine phosphorylation. J Smooth Muscle Res 2013; 49:26-45. [PMID: 24133693 PMCID: PMC5137315 DOI: 10.1540/jsmr.49.26] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Rho-associated kinase (ROK) activation plays an important role in K+-induced
contraction of rat caudal arterial smooth muscle (Mita et al., Biochem J. 2002; 364:
431–40). The present study investigated a potential role for tyrosine kinase activity in
K+-induced RhoA activation and contraction. The non-selective tyrosine kinase
inhibitor genistein, but not the src family tyrosine kinase inhibitor PP2, inhibited
K+-induced sustained contraction (IC50 = 11.3 ± 2.4 µM). Genistein
(10 µM) inhibited the K+-induced increase in myosin light chain
(LC20) phosphorylation without affecting the Ca2+ transient. The
tyrosine phosphatase inhibitor vanadate induced contraction that was reversed by genistein
(IC50 = 6.5 ± 2.3 µM) and the ROK inhibitor Y-27632 (IC50 = 0.27 ±
0.04 µM). Vanadate also increased LC20 phosphorylation in a genistein- and
Y-27632-dependent manner. K+ stimulation induced translocation of RhoA to the
membrane, which was inhibited by genistein. Phosphorylation of MYPT1 (myosin-targeting
subunit of myosin light chain phosphatase) was significantly increased at Thr855 and
Thr697 by K+ stimulation in a genistein- and Y-27632-sensitive manner. Finally,
K+ stimulation induced genistein-sensitive tyrosine phosphorylation of
proteins of ∼55, 70 and 113 kDa. We conclude that a genistein-sensitive tyrosine kinase,
activated by the membrane depolarization-induced increase in
[Ca2+]i, is involved in the RhoA/ROK activation and sustained
contraction induced by K+. Ca2+ sensitization, myosin light chain
phosphatase, RhoA, Rho-associated kinase, tyrosine kinase
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Affiliation(s)
- Mitsuo Mita
- Department of Pharmacodynamics, Meiji Pharmaceutical
University, Japan
| | - Hitoshi Tanaka
- Department of Pharmacodynamics, Meiji Pharmaceutical
University, Japan
| | - Hayato Yanagihara
- Department of Pharmacodynamics, Meiji Pharmaceutical
University, Japan
| | - Jun-ichi Nakagawa
- Department of Pharmacodynamics, Meiji Pharmaceutical
University, Japan
| | - Shigeru Hishinuma
- Department of Pharmacodynamics, Meiji Pharmaceutical
University, Japan
| | - Cindy Sutherland
- Smooth Muscle Research Group, Department of Biochemistry and
Molecular Biology, University of Calgary, Canada
| | - Michael P. Walsh
- Smooth Muscle Research Group, Department of Biochemistry and
Molecular Biology, University of Calgary, Canada
| | - Masaru Shoji
- Department of Pharmacodynamics, Meiji Pharmaceutical
University, Japan
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12
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Zhao L, Wang Z, Ruan YC, Zhou WL. Cellular mechanism underlying the facilitation of contractile response of vas deferens smooth muscle by sodium orthovanadate. Mol Cell Biochem 2012; 366:149-57. [PMID: 22476902 DOI: 10.1007/s11010-012-1292-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Accepted: 03/17/2012] [Indexed: 10/28/2022]
Abstract
In the earlier study, sodium orthovanadate (SOV) has been reported to be a powerful inhibitor of (Na(+), K(+)) adenosine triphosphatase, exhibit widespread actions on the renal and cardiovascular systems, induces smooth muscle contraction by inhibiting the phosphorylation of the protein tyrosine phosphatases. In the current study, we aimed to investigate the cellular mechanisms by which SOV facilitated contractile response of vas deferens smooth muscle and its potential therapeutic advantage. Exogenous application of ATP and NA-caused contraction was strengthened by pretreatment with SOV. This facilitation was inhibited not by bath with the inhibitor of P2 receptor, PPADS, or the inhibitor of α1 receptor, Prazosin, but by bath with the protein tyrosine kinase inhibitor, Genistein. SOV induced a sustained increase in intracellular Ca(2+) of smooth muscle cells, which was abolished by 100 μM Genistein or Ca(2+)-free solution. The facilitation of SOV could also be inhibited by the selective inhibitors of TRP channel, 2-APB and non-selective cation channel, Gd(3+), Ni(+). The in vivo study showed that peritoneal injection of SOV in dystrophic mice (mdx mice) enhanced the contraction of vas deferens smooth muscle stimulated by electrical field stimulation, ATP, noradrenaline, or KCl. The above results suggest that SOV facilitates the concentration of vas deferens smooth muscle through the tyrosine phosphorylation activated the non-selective cation channels, which has potential use in the therapy for muscle dysfunction.
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Affiliation(s)
- Lei Zhao
- Department of Physiology, Guangzhou Medical University, 195 Dongfeng West Road, Guangzhou 510182, People's Republic of China.
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13
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Knock GA, Ward JPT. Redox regulation of protein kinases as a modulator of vascular function. Antioxid Redox Signal 2011; 15:1531-47. [PMID: 20849377 DOI: 10.1089/ars.2010.3614] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Reactive oxygen species (ROS) are continuously generated in vascular tissues by various oxidoreductase enzymes. They contribute to normal cell signaling, and modulate vascular smooth muscle tone and endothelial permeability in response to physiological agonists and to various cellular stresses and environmental factors, such as hypoxia. While concentrations of ROS are normally tightly controlled by cellular redox buffer systems, if produced in excess they may contribute to vascular disease. Protein kinases are essential components of most cell signaling pathways, including those involving ROS. The functioning of several members of this highly diverse group of enzymes, which include receptor and nonreceptor tyrosine kinases, protein kinase C, mitogen-activated kinases, and Rho-kinase, are modified by ROS, either through direct oxidative modification or indirectly through modification of associated proteins such as tyrosine phosphatases and monomeric G proteins. In this review, we discuss the molecular mechanisms of redox modification of these proteins, the downstream pathways affected, the often complex interaction between major kinase pathways, and feedback to ROS production itself. We also discuss complicating factors such as differential actions of superoxide anion and hydrogen peroxide, questions concerning concentration dependence, and the significance of signaling microdomains.
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Affiliation(s)
- Greg A Knock
- Division of Asthma, Allergy, and Lung Biology, King's College London, Stamford Street, London, United Kingdom.
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14
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Bhuiyan MS, Fukunaga K. Cardioprotection by vanadium compounds targeting Akt-mediated signaling. J Pharmacol Sci 2009; 110:1-13. [PMID: 19423951 DOI: 10.1254/jphs.09r01cr] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Treatment with inorganic and organic compounds of vanadium has been shown to exert a wide range of cardioprotective effects in myocardial ischemia/reperfusion-induced injury, myocardial hypertrophy, hypertension, and vascular diseases. Furthermore, administration of vanadium compounds improves cardiac performance and smooth muscle cell contractility and modulates blood pressure in various models of hypertension. Like other vanadium compounds, we documented bis(1-oxy-2-pyridinethiolato) oxovanadium (IV) [VO(OPT)] as a potent cardioprotective agent to elicit cardiac functional recovery in myocardial infarction and pressure overload-induced hypertrophy. Vanadium compounds activate Akt signaling through inhibition of protein tyrosine phosphatases, thereby eliciting cardioprotection in myocardial ischemia/reperfusion-induced injury and myocardial hypertrophy. Vanadium compounds also promote cardiac functional recovery by stimulation of glucose transport in diabetic heart. We here discuss the current understanding of mechanisms underlying vanadium compound-induced cardioprotection and propose a novel therapeutic strategy targeting for Akt signaling to rescue cardiomyocytes from heart failure.
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Clyman RI, Waleh N, Kajino H, Roman C, Mauray F. Calcium-dependent and calcium-sensitizing pathways in the mature and immature ductus arteriosus. Am J Physiol Regul Integr Comp Physiol 2007; 293:R1650-6. [PMID: 17652360 DOI: 10.1152/ajpregu.00300.2007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Studies performed in sheep and baboons have shown that after birth, the normoxic muscle media of ductus arteriosus (DA) becomes profoundly hypoxic as it constricts and undergoes anatomic remodeling. We used isolated fetal lamb DA (pretreated with inhibitors of prostaglandin and nitric oxide production) to determine why the immature DA fails to remain tightly constricted during the hypoxic phase of remodeling. Under normoxic conditions, mature DA constricts to 70% of its maximal active tension (MAT). Half of its normoxic tension is due to Ca(2+) entry through calcium L-channels and store-operated calcium (SOC) channels. The other half is independent of extracellular Ca(2+) and is unaffected by inhibitors of sarcoplasmic reticulum (SR) Ca(2+) release (ryanodine) or reuptake [cyclopiazonic acid (CPA)]. The mature DA relaxes slightly during hypoxia (to 60% MAT) due to decreases in calcium L-channel-mediated Ca(2+) entry. Inhibitors of Rho kinase and tyrosine kinase inhibit both Ca(2+)-dependent and Ca(2+)-independent DA tension. Although Rho kinase activity may increase during gestation, immature DA develop lower tensions than mature DA, primarily because of differences in the way they process Ca(2+). Calcium L-channel expression increases with advancing gestation. Under normoxic conditions, differences in calcium L-channel-mediated Ca(2+) entry account for differences in tension between immature (60% MAT) and mature (70% MAT) DA. Under hypoxic conditions, differences in both calcium L-channel-dependent and calcium L-channel-independent Ca(2+) entry, account for differences in tension between immature (33% MAT) and mature (60% MAT) DA. Stimulation of Ca(2+) entry through reverse-mode Na(+)/Ca(2+) exchange or CPA-induced SOC channel activity constrict the DA and eliminate differences between immature and mature DA during both hypoxia and normoxia.
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Affiliation(s)
- Ronald I Clyman
- Cardiovascular Research Institute and Department of Pediatrics, University of California, San Francisco, 513 Parnassus Ave., Rm. 1408 HSW, UCSF Box 0544, San Francisco, CA 94143-0544, USA.
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16
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Zhang LP, Yin JX, Liu Z, Zhang Y, Wang QS, Zhao J. Effect of resveratrol on L-type calcium current in rat ventricular myocytes. Acta Pharmacol Sin 2006; 27:179-83. [PMID: 16412267 DOI: 10.1111/j.1745-7254.2006.00250.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
AIM To study the effect of resveratrol on L-type calcium current (I(Ca-L)) in isolated rat ventricular myocytes and the mechanisms underlying these effects. METHODS I(Ca-L) was examined in isolated single rat ventricular myocytes by using the whole cell patch-clamp recording technique. RESULTS Resveratrol (10-40 micromol/L) reduced the peak amplitude of I(Ca-L) and shifted the current-voltage (I-V) curve upwards in a concentration-dependent manner. Resveratrol (10, 20, 40 micromol/L) decreased the peak amplitude of I(Ca-L) from -14.2+/-1.5 pA/pF to -10.5+/-1.5 pA/pF (P<0.05), -7.5+/-2.4 pA/pF (P<0.01), and -5.2+/-1.2 pA/pF (P<0.01), respectively. Resveratrol (40 micromol/L) shifted the steady-state activation curve of I(Ca-L) to the right and changed the half-activation potential (V0.5) from -19.4+/-0.4 mV to -15.4+/-1.9 mV (P<0.05). Resveratrol at a concentration of 40 micromol/L did not affect the steady-state inactivation curve of I(Ca-L), but did markedly shift the time-dependent recovery curve of I(Ca-L) to the right, and slow down the recovery of I(Ca-L) from inactivation. Sodium orthovanadate (Na(3)VO(4); 1 mmol/L), a potent inhibitor of tyrosine phosphatase, significantly inhibited the effects of resveratrol (P<0.01). CONCLUSION Resveratrol inhibited I(Ca-L) mainly by inhibiting the activation of L-type calcium channels and slowing down the recovery of L-type calcium channels from inactivation. This inhibitory effect of resveratrol was mediated by the inhibition of protein tyrosine kinase in rat ventricular myocytes.
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Affiliation(s)
- Li-ping Zhang
- Department of Physiology, Institute of Basic Medicine, Hebei Medical University, Shijiazhuang 050017, China
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17
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Yu J, Mizumoto K, Kakutani T, Hasegawa A, Ogawa K, Hatano Y. Comparison of the effects of isoflurane and sevoflurane on protein tyrosine phosphorylation-mediated vascular contraction. Acta Anaesthesiol Scand 2005; 49:852-8. [PMID: 15954971 DOI: 10.1111/j.1399-6576.2005.00699.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Isoflurane induces greater effects on vasodilation and decreasing blood pressure than sevoflurane. Tyrosine kinase-catalyzed protein tyrosine phosphorylation plays an important role in regulating vascular smooth muscle contraction. The aim of the present study was to compare the effects of isoflurane and sevoflurane on tyrosine phosphorylation-mediated vascular constriction, by assessing the degree of sodium orthovanadate (Na(3)VO(4), tyrosine phosphatase inhibitor)-induced contraction and protein tyrosine phosphorylation of rat aortic smooth muscle. METHODS Na(3)VO(4)-induced contraction and protein tyrosine phosphorylation of rat aortic smooth muscle were measured in the presence of genistein, a tyrosine kinase inhibitor, and different concentrations of isoflurane and sevoflurane, using isometric force measurement and Western blot, respectively. RESULTS Na(3)VO(4) (10(-4) M) induced sustained contraction and tyrosine phosphorylation of substrates that were both markedly attenuated in the presence of genistein (5 x 10(-5) M). Isoflurane and sevoflurane dose-dependently (1, 2, 3 MAC) attenuated the Na(3)VO(4)-induced contraction (P < 0.05-0.005, n = 8), with a greater degree of inhibition by isoflurane than sevoflurane at 2 MAC (P < 0.01) and 3 MAC (P < 0.05). Both anesthetics also attenuated the total band density of the Na(3)VO(4)-induced, tyrosine-phosphorylated substrates in a concentration-dependent manner (P < 0.05-0.005, n = 4), with much greater attenuation by isoflurane than sevoflurane at 1 and 2 MAC (P < 0.05), respectively. CONCLUSION The results of the present study demonstrate that isoflurane exhibits a greater degree of inhibition on the Na(3)VO(4)-stimulated contraction and protein tyrosine phosphorylation of rat aortic smooth muscle compared with sevoflurane. These findings suggest that isoflurane depresses the protein tyrosine phosphorylation-mediated contraction of vascular smooth muscle to a greater degree than sevoflurane.
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Affiliation(s)
- J Yu
- Department of Anesthesiology, Wakayama Medical University, Wakayama, Japan
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18
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Ding X, Murray PA. Regulation of pulmonary venous tone in response to muscarinic receptor activation. Am J Physiol Lung Cell Mol Physiol 2005; 288:L131-40. [PMID: 15377494 DOI: 10.1152/ajplung.00230.2004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We investigated cellular mechanisms that mediate or modulate the vascular response to muscarinic receptor activation (ACh) in pulmonary veins (PV). Isometric tension was measured in isolated canine PV rings with endothelium (E+) and without endothelium (E−). Tension and intracellular Ca2+concentration ([Ca2+]i) were measured simultaneously in fura-2-loaded E− PV strips. In the absence of preconstriction, ACh (0.01–10 μM) caused dose-dependent contraction in E+ and E− rings. ACh contraction was potentiated by removing the endothelium or by nitric oxide (NO) synthase inhibition ( N-nitro-l-arginine methyl ester, P = 0.001). Cyclooxygenase inhibition (indomethacin) reduced ACh contraction in both E+ and E− PV rings ( P = 0.013 and P = 0.037, respectively). ACh contraction was attenuated by inhibitors of voltage-operated Ca2+channels (nifedipine, P < 0.001), inositol-1,4,5-trisphosphate (IP3)-mediated Ca2+release (2-aminoethoxydiphenyl borate, P = 0.001), PKC (bisindolylmaleimide I, P = 0.001), Rho-kinase (Y-27632, P = 0.002), and tyrosine kinase (TK; tyrphostin 47, P = 0.015) in E− PV rings. ACh (1 μM) caused a leftward shift in the [Ca2+]i-tension relationship ( P = 0.015), i.e., ACh increased myofilament Ca2+sensitivity. Inhibition of PKC, Rho-kinase, and TK attenuated the ACh-induced increase in myofilament Ca2+sensitivity ( P < 0.001, P < 0.001, and P = 0.024, respectively). These findings indicate that in canine PV, ACh contraction is modulated by NO and partially mediated by metabolites of the cyclooxygenase pathway and involves Ca2+influx through voltage-operated Ca2+channels and IP3-mediated Ca2+release. In addition, ACh induces increased myofilament Ca2+sensitivity, which requires the PKC, Rho-kinase, and TK pathways.
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Affiliation(s)
- Xueqin Ding
- Center for Anesthesiology Research, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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19
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Abstract
Inorganic and organic compounds of vanadium have been shown to exhibit a large range of insulinomimetic effects in the cardiovascular system, including stimulation of glucose transporter 4 (GLUT-4) translocation and glucose transport in adult cardiomyocytes. Furthermore, administration of vanadium compounds improves cardiac performance and smooth muscle contractility, and modulates blood pressure in various models of hypertension and insulin resistance. Vanadium compounds are potent inhibitors of protein tyrosine phosphatases. As a result, they promote an increase in protein tyrosine phosphorylation of several key components of the insulin signaling pathway, leading to the upregulation of phosphatidylinositol 3-kinase and protein kinase B, two enzymes involved in mediating GLUT-4 trans location and glucose transport. In addition, vanadium has also been shown to activate p38 mitogen-activated protein kinase and increase Ca2+levels in several cell types. The ability of vanadium compounds to activate these signaling events may be responsible for their ability to modulate cardiovascular functions.Key words: vanadium compounds, glucose transport, smooth muscle contractility, insulin signaling pathway.
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Affiliation(s)
- Lise Coderre
- Research Center, Centre hospitalier de l'Université de Montréal, Hôtel-Dieu, Department of Medicine, Université de Montréal, QC, Canada
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20
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Uzun O, Tuncay Demiryürek A. Involvement of tyrosine kinase pathway in acute hypoxic vasoconstriction in sheep isolated pulmonary vein. Vascul Pharmacol 2004; 40:175-81. [PMID: 13678650 DOI: 10.1016/s1537-1891(03)00051-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Tyrosine kinase pathway has been shown to be involved in the effects of hypoxia in pulmonary arteries, but its role in pulmonary vein is not known. The aims of this study were to determine the effect of hypoxia in sheep isolated pulmonary veins and to identify the role of tyrosine kinase pathway in hypoxic response. Genistein and tyrphostin were used as selective tyrosine kinase inhibitors, and sodium orthovanadate was administered for tyrosine kinase activation. Hypoxia (95% N(2) to 5% CO(2)) caused a vasoconstriction either under resting tone or in U46619-precontracted pulmonary veins. Genistein and tyrphostin inhibited hypoxia-induced vasoconstriction both under resting tone and in precontracted veins, while sodium orthovanadate increased these hypoxic contractions. Our findings suggest that tyrosine kinase pathway is involved in hypoxic pulmonary vasoconstriction in sheep isolated pulmonary vein rings.
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Affiliation(s)
- Ozge Uzun
- Department of Pharmacology, Faculty of Medicine, Abant Izzet Baysal University, 81620 Konuralp, Düzce, Turkey.
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21
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Adegunloye BJ, Su X, Camper EV, Moreland RS. Sensitivity of rabbit aorta and mesenteric artery to norepinephrine: role of tyrosine kinases. Eur J Pharmacol 2003; 476:201-9. [PMID: 12969767 DOI: 10.1016/s0014-2999(03)02183-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We tested the hypothesis that the differential sensitivity of rabbit aorta and mesenteric artery to norepinephrine is due to tyrosine kinase activity. The EC50 of aorta to norepinephrine was 6.5 times more sensitive than that in mesenteric artery. Basal myosin light chain phosphorylation was significantly greater in aorta as compared to mesenteric artery. Vanadate increased norepinephrine sensitivity significantly more in mesenteric artery than aorta, whereas genistein had the opposite effect. Basal phosphotyrosine levels were significantly higher in aorta than in mesenteric artery, the percentage increase in total tyrosine phosphorylated protein was significantly higher in mesenteric artery. These results suggest that the higher basal phosphotyrosine levels in the aorta may be responsible for the higher basal level of myosin light chain phosphorylation and this may be the basis for the higher sensitivity of the aorta to norepinephrine when compared with the mesenteric artery.
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MESH Headings
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/physiology
- Blotting, Western
- Electrophoresis, Polyacrylamide Gel
- Genistein/pharmacology
- In Vitro Techniques
- Isometric Contraction/drug effects
- Male
- Mesenteric Arteries/drug effects
- Mesenteric Arteries/metabolism
- Mesenteric Arteries/physiology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiology
- Myosin Light Chains/metabolism
- Norepinephrine/pharmacology
- Phosphorylation
- Phosphotyrosine/metabolism
- Protein-Tyrosine Kinases/antagonists & inhibitors
- Protein-Tyrosine Kinases/metabolism
- Rabbits
- Receptors, Adrenergic/metabolism
- Time Factors
- Vasoconstrictor Agents/pharmacology
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Affiliation(s)
- Banji J Adegunloye
- Department of Pharmacology and Physiology, Drexel University College of Medicine, 245 N 15th Street, MS# 488, Philadelphia, PA 19102, USA
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22
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Shin HK, Lee JH, Kim KY, Kim CD, Lee WS, Rhim BY, Hong KW. Impairment of autoregulatory vasodilation by NAD(P)H oxidase-dependent superoxide generation during acute stage of subarachnoid hemorrhage in rat pial artery. J Cereb Blood Flow Metab 2002; 22:869-77. [PMID: 12142572 DOI: 10.1097/00004647-200207000-00012] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study assessed the mechanism(s) by which the autoregulatory vasodilation of rat pial artery in response to acute hypotension during the acute phase of subarachnoid hemorrhage (SAH) was markedly blunted. Increased superoxide production from the cerebral vessels in response to NAD(P)H at 24 hours after SAH + NG-nitro-l-arginine methyl ester (l-NAME) (10 mg/kg) was inhibited by intracisternal administration of a tyrosine kinase inhibitor genistein (10 micromol/L) and Rac inhibitor Clostridium difficile toxin B (1 ng/mL) and a flavoenzyme inhibitor diphenyleneiodonium (10 micromol/L). The expression of gp91phox was enhanced by SAH + l-NAME from 12 to 24 hours, which was inhibited by genistein and toxin B, but not the p22phox. Increased membrane translocation of Rac after SAH + l-NAME was attenuated by both genistein and toxin B, whereas increased tyrosine kinase activity was blocked by genistein, but not by toxin B. The blunted autoregulatory vasodilation to acute hypotension was effectively recovered by genistein and C. difficile toxin B as well as by diphenyleneiodonium. In conclusion, SAH during acute stage causes an increase in NAD(P)H oxidase-dependent superoxide formation in cerebral vessels, which is due to activation of tyrosine phosphorylation-dependent increased expression of gp91phox mRNA and translocation of Rac protein, thereby resulting in a significant reduction of autoregulatory vasodilation.
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Affiliation(s)
- Hwa Kyoung Shin
- Department of Pharmacology, College of Medicine, Research Institute of Genetic Engineering, Pusan National University, Korea
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23
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Fang LH, Kwon SC, Zhang YH, Ahn HY. Tyrosine kinase participates in vasoconstriction through a Ca(2+)- and myosin light chain phosphorylation-independent pathway. FEBS Lett 2002; 512:282-6. [PMID: 11852096 DOI: 10.1016/s0014-5793(02)02235-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study was undertaken to determine the role of tyrosine kinase on intracellular Ca(2+) ([Ca(2+)](i)), myosin light chain (MLC) phosphorylation, and contraction caused by norepinephrine (NE) in rat aorta. NE induced a sustained contraction with an increase of [Ca(2+)](i). On the other hand, NE increased the phosphorylation of the 20 kDa MLC transiently. Pretreatment with genistein and tyrophostin 25, tyrosine kinase inhibitors, significantly inhibited NE-induced contraction, but did not affect the increase of [Ca(2+)](i) and MLC phosphorylation. These results suggest that tyrosine kinase may regulate the NE-mediated contraction without altering [Ca(2+)](i) and MLC phosphorylation in rat aorta.
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Affiliation(s)
- Lian Hua Fang
- Department of Pharmacology, College of Medicine, Chungbuk National University, 361-763, Cheongju, South Korea
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24
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Singer CA, Vang S, Gerthoffer WT. Coupling of M(2) muscarinic receptors to Src activation in cultured canine colonic smooth muscle cells. Am J Physiol Gastrointest Liver Physiol 2002; 282:G61-8. [PMID: 11751158 DOI: 10.1152/ajpgi.00100.2002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The purpose of this study was to determine whether Src tyrosine kinases are one of the signaling intermediaries linking M(2) receptor stimulation to extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) in cultures of canine colonic smooth muscle cells (CSMC). RT-PCR studies demonstrate expression of multiple Src tyrosine kinases, including Src, Fyn, and Yes, in CSMC. Muscarinic stimulation of CSMC with 10 microM ACh results in a twofold increase in Src activity within 10 min but does not increase the activity of Fyn. Treatment with the M(2) antagonist AF-DX 116 (10 microM) blocks ACh-stimulated Src activation in primary CSMC cultures that express both M(2) and M(3) receptors and in first-passage CSMC cultures that express predominantly M(2) receptors. Alkylation of M(3) receptors with 100 nM N,N-dimethyl-4-piperidinyl diphenylacetate mustard has no effect on Src activity. Treatment with the pyrazolopyrimidine Src inhibitor PP1 (10 microM) or AF-DX 116 (10 microM) blocks ACh-stimulated ERK phosphorylation. Together these results indicate that M(2) receptors are coupled to Src tyrosine kinase and subsequent activation of ERK in cultured CSMC.
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Affiliation(s)
- Cherie A Singer
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada 89557-0046, USA.
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25
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Barbagallo M, Dominguez LJ, Resnick LM. Insulin-mimetic action of vanadate: role of intracellular magnesium. Hypertension 2001; 38:701-4. [PMID: 11566960 DOI: 10.1161/hy09t1.095392] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The insulin-mimetic effect of vanadate is well established, and vanadate has been shown to improve insulin sensitivity in diabetic rats and humans. Although the exact mechanism(s) remain undefined, we have previously demonstrated a direct relation of intracellular free magnesium (Mg(i)) levels to glucose disposal, to insulinemic responses following glucose loading, and to insulin-induced ionic effects. To investigate whether the insulin-mimetic effects of vanadate could similarly be mediated by Mg(i), we utilized (31)P-nuclear magnetic resonance spectroscopy to measure Mg(i) in erythrocytes from normal (NL, n=10) and hypertensive (HTN, n=12) subjects, before and after incubation with insulin and with different doses of sodium vanadate. In NL, vanadate elevated Mg(i) levels, with maximum efficacy at 50 7 micromol/L (186+/-6 to 222+/-6 7micromol/L, P>0.01), as did physiologically maximal doses of insulin, 200 7microU/mL (185+/-6 to 222+/-8 7micromol/L, P<0.01). In HTN, only vanadate, but not insulin, increased Mg(i) (insulin: 173+/-7 to 180+/-9 7micromol/L, P=NS; vanadate: 170+/-7 to 208+/-10 7micromol/L, P<0.01). Mg(i) responses to insulin (r=0.637, P<0.001), but not to vanadate (r=0.15, P=NS), were closely and directly related to basal Mg(i) levels. We conclude that (1) both vanadate and insulin stimulate erythrocyte Mg(i) levels; (2) cellular Mg(i) responses to insulin, but not to vanadate, depend on basal Mg(i) content-the lower the basal Mg(i), the less the Mg(i) response to insulin. As such, (3) Mg(i) responses to vanadate were equivalent among HTN and NL, whereas HTN cells exhibited blunted Mg(i) responses to insulin, and (4) the ability of vanadate to improve insulin sensitivity clinically may be mediated, at least in part, by its ability to increase Mg(i) levels, which in turn, helps to determine cellular insulin action.
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Affiliation(s)
- M Barbagallo
- Institute of Internal Medicine and Geriatrics, University of Palermo, Italy.
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26
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Hong KW, Shin HK, Kim CD, Lee WS, Rhim BY. Restoration of vasodilation and CBF autoregulation by genistein in rat pial artery after brain injury. Am J Physiol Heart Circ Physiol 2001; 281:H308-15. [PMID: 11406498 DOI: 10.1152/ajpheart.2001.281.1.h308] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study determined whether, after fluid percussion injury (FPI), tyrosine kinase activation is coupled to inhibition of K(+) channels and alteration in cerebral blood flow (CBF) autoregulation in the rat pial artery. Injury of moderate severity (2--2.5 atm) was produced by FPI in anesthetized rats equipped with a closed cranial window. The suppressed vasodilation of the pial arterioles to calcitonin gene-related peptide (CGRP) and levcromakalim (LMK) and altered lower limit of CBF autoregulation after FPI were restored by genistein but not by daidzein, an inactive analog. Vasodilation to S-nitroso-N-acetyl penicillamine (0.1--10 micromol/l) was, however, little influenced after FPI. The restored vasodilation was decreased by sodium orthovanadate, suggesting the reciprocal action of tyrosine phosphorylation and dephosphorylation. After FPI, CGRP-induced vasodilation restored by genistein (10 micromol/l) was strongly antagonized by iberiotoxin but not by glibenclamide, whereas LMK-induced vasodilation was, in contrast, inhibited by glibenclamide but not by iberiotoxin. Taken together, we suggest that, after FPI, activation of tyrosine kinase links the inhibition of K(+) channels to impaired autoregulatory vasodilation in response to acute hypotension and alteration in CBF autoregulation in the rat pial artery.
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Affiliation(s)
- K W Hong
- Department of Pharmacology, College of Medicine, Pusan National University, Pusan 602-739, Korea.
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27
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Lajas AI, Sierra V, Camello PJ, Salido GM, Pariente JA. Vanadate inhibits the calcium extrusion in rat pancreatic acinar cells. Cell Signal 2001; 13:451-6. [PMID: 11384844 DOI: 10.1016/s0898-6568(01)00161-9] [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: 11/19/2022]
Abstract
Our objective was to evaluate the role of vanadate on calcium extrusion in Fura-2-loaded rat pancreatic acinar cells by digital microscopic fluorimetry and spectrofluorimetry. In the absence of extracellular calcium, perfusion of pancreatic acinar cells with 1 nM CCK-8 and 1 mM vanadate did not significantly affect the typical transient calcium spike induced by CCK-8, but the plateau phase of calcium in response to CCK-8 remained elevated. In addition, vanadate was able to inhibit calcium efflux evoked by CCK-8 when we determined directly calcium transport across plasma membrane using Calcium Green-5N hexapotassium salt (cell impermeant form) in cell populations. The effect of vanadate on calcium extrusion was strongly blocked by the sulfhydryl-reducing agent dithiothreitol (DTT). The present results demonstrate that vanadate is able to irreversibly inhibit the calcium extrusion. This effect of vanadate can be blocked using DTT, indicating that its action is probably mediated by oxidation of sulfhydryl groups of Ca2+-ATPases.
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Affiliation(s)
- A I Lajas
- Department of Physiology. Faculty of Veterinary Science, University of Extremadura, PO Box 643, 10071, Cáceres, Spain.
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28
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Dahdah NS, Russo P, Wagerle LC. Phosphorylation in coronary artery cold-induced contraction in the newborn lamb. Cryobiology 2001; 42:40-8. [PMID: 11336488 DOI: 10.1006/cryo.2001.2299] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Myocardial dysfunction after hypothermic protection has been linked to various mechanisms. Coronary vasospasm in particular may be responsible for ischemic injury during reperfusion. Herein we hypothesized that coronary arteries (CA) sustain a cold-induced contraction during hypothermia mediated by a protein tyrosine kinase (PTK)-/protein tyrosine phosphatase (PTP)-dependent pathway. Isolated newborn lamb CA rings were studied in a tissue bath for isometric contraction during 2-h profound (17 degrees C) or ultra-profound (7 degrees C) hypothermia. In parallel, protein tyrosine phosphorylation was evaluated by use of the Western blot technique. Na-orthovanadate (SOV) and genestein (GEN) were used separately and in combination to evaluate the effect of PTK/PTP activation on CA contraction and tyrosine phosphorylation during cooling (17 or 7 degrees C) vs 37 degrees C. Cooling from 37 to 7 degrees C induced transient contraction at approximately 17 degrees C (29% KCl response), which was more prominent during rewarming to 37 degrees C (36% KCl). Cooling to 17 degrees C resulted in sustained contraction (7-10% KCl), which was reversible upon rewarming. Cold-induced contraction was significantly enhanced by SOV (7- to 10-fold at 17 degrees C; 2-fold at 7 degrees C) and abolished by GEN. Concurrently, tyrosine phosphorylation of 33-, 45-, and 104-kDa proteins increased during cooling (35-100% at 17 degrees C; 46-66% at 7 degrees C). Tyrosine phosphorylation was similarly enhanced by SOV (1.7- to 2.3-fold at 17 degrees C; 2.9- to 3.9-fold at 7 degrees C) and abolished by GEN in the presence or absence of SOV. These results support a prominent role for the PTK/PTP signal transduction pathway in the coronary artery cold-induced contraction. This information provides one possible biomolecular mechanism linked to ischemia/reperfusion pathophysiology of CA in neonatal hearts exposed to hypothermic myocardial protection.
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Affiliation(s)
- N S Dahdah
- Department of Pediatrics, MetroHealth Medical Center, Cleveland, Ohio 44109, USA
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29
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Shafrir E, Spielman S, Nachliel I, Khamaisi M, Bar-On H, Ziv E. Treatment of diabetes with vanadium salts: general overview and amelioration of nutritionally induced diabetes in the Psammomys obesus gerbil. Diabetes Metab Res Rev 2001; 17:55-66. [PMID: 11241892 DOI: 10.1002/1520-7560(2000)9999:9999<::aid-dmrr165>3.0.co;2-j] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Numerous investigations have demonstrated the beneficial effect of vanadium salts on diabetes in streptozotocin (STZ)-diabetic rats, in rodents with genetically determined diabetes and in human subjects. The amelioration of diabetes included the abolition of hyperglycemia, preservation of insulin secretion, reduction in hepatic glucose production, enhanced glycolysis and lipogenesis and improved muscle glucose uptake through GLUT4 elevation and translocation. The molecular basis of vanadium salt action is not yet fully elucidated. Although evidence has been provided that the insulin receptor is activated, the possibility exists that cytosolic non-receptor tyrosine kinase, direct phosphorylation of IRS-1 and activation of PI3-K, leading to GLUT4 translocation, are involved. The raised phosphorylation of proteins in the insulin signaling pathway appears to be related to the inhibition of protein tyrosine phosphatase (PTPase) activity by vanadium salts. NOVEL EXPERIMENTS The model utilized in our study was Psammomys obesus (sand rat), a desert gerbil which becomes hyperglycemic and hyperinsulinemic on an ad libitum high energy (HE) diet. In contrast to the previously investigated insulin deficient models, vanadyl sulphate was used to correct insulin resistance and hyperinsulinemia, which led to beta-cell loss. Administration of 5 mg/kg vanadyl sulfate for 5 days resulted in prolonged restoration of normoglycemia and normoinsulinemia in most animals, return of glucose tolerance to normal, and a reduction of hepatic phosphoenolpyruvate carboxykinase activity. There was no change in food consumption and in regular growth during or after the vanadyl treatment. Pretreatment with vanadyl sulfate, followed by transfer to a HE diet, significantly delayed the onset of hyperglycemia. Hyperinsulinemic-euglycemic clamp of vanadyl sulfate treated Psammomys demonstrated an improvement in glucose utilization. However, vanadyl sulfate was ineffective when administered to animals which lost their insulin secretion capacity on protracted HE diet, but substantially reduced the hyperglycemia when given together with exogenous insulin. The in vitro insulin activation of liver and muscle insulin receptors isolated from vanadyl treated Psammomys was ineffective. The in vivo vanadyl treatment restored muscle GLUT4 total protein and mRNA contents in addition to membrane GLUT4 protein, in accordance with the increased glucose utilization during the clamp study. These results indicate that short-term vanadyl sulfate treatment corrects the nutritionally induced, insulin resistant diabetes. This action requires the presence of insulin for its beneficial effect. Thus, vanadyl action in P. obesus appears to be the result of insulin potentiation rather than mimicking, with activation of the signaling pathway proteins leading to GLUT4 translocation, probably distal to the insulin receptor.
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Affiliation(s)
- E Shafrir
- Department of Biochemistry and Diabetes Research Unit, Hadassah University Hospital and Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.
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30
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Melis A, Watts SW, Florian J, Klarr S, Webb RC. Insulin-like growth factor inhibits vascular contraction to 5-hydroxytryptamine: involvement of tyrosine phosphatase. GENERAL PHARMACOLOGY 2000; 34:137-45. [PMID: 10974421 DOI: 10.1016/s0306-3623(00)00055-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
This study tests the hypothesis that insulin-like growth factor 1 (IGF-1)-induced vasodilation is due to the stimulation of tyrosine phosphatase. Rat aortic segments (endothelium intact) were placed in muscle baths for force measurement. Segments were contracted to serotonin [5-hydroxytyptamine (5-HT), 10(-7)-10(-5) M] before and after incubation with IGF-1 (10-100 nM; 90 min). IGF-1 caused a 20% inhibition of 5-HT-induced contractions. This inhibition was reversed by the tyrosine phosphatase inhibitors sodium orthovanadate and molybdate. Orthovanadate did not alter inhibitory properties of the calcium channel antagonist verapamil, suggesting that the phosphatase inhibitors were relatively specific. IGF-1-induced inhibition was not altered by blockade of nitric oxide synthase. Western blot analysis confirmed that the 5-HT-induced stimulation of tyrosine phosphorylation of the 42-kDa extracellular signal-regulated mitogen-activated protein kinase protein was reduced by IGF-1 (52% inhibition), an inhibition that was attenuated by orthovanadate. These data are consistent with the hypothesis that the vasodilator activity of IGF-1 is mediated by the activation of a tyrosine phosphatase.
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MESH Headings
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/enzymology
- Aorta, Thoracic/physiology
- Drug Synergism
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiology
- Enzyme Inhibitors/pharmacology
- In Vitro Techniques
- Insulin-Like Growth Factor I/pharmacology
- Male
- Mitogen-Activated Protein Kinases/metabolism
- Molybdenum/pharmacology
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/physiology
- Nitric Oxide/physiology
- Nitric Oxide Synthase/antagonists & inhibitors
- Nitroarginine/pharmacology
- Phosphorylation/drug effects
- Protein Tyrosine Phosphatases/antagonists & inhibitors
- Protein Tyrosine Phosphatases/metabolism
- Rats
- Rats, Sprague-Dawley
- Serotonin/pharmacology
- Serotonin Antagonists/pharmacology
- Vanadates/pharmacology
- Vasoconstriction/drug effects
- Vasoconstriction/physiology
- Vasodilator Agents/pharmacology
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Affiliation(s)
- A Melis
- Department of Physiology, University of Michigan Medical School, Ann Arbor, MI 48109-0622, USA
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31
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van Lunteren E, Snajdar RM. Attenuation of rat diaphragm low-frequency fatigue by vanadate in vitro. RESPIRATION PHYSIOLOGY 1999; 117:121-30. [PMID: 10563440 DOI: 10.1016/s0034-5687(99)00062-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Sodium vanadate inhibits protein tyrosine phosphatases, including in skeletal muscle. Vanadate increases contractile force of airway, vascular and gastrointestinal smooth muscle. The present study tested the hypothesis that vanadate augments skeletal muscle contractility. Rat diaphragm muscle strips (n=26 from 12 animals) were studied in vitro at 37 degrees C. Muscles contracted isometrically while stimulated supramaximally with one of two protocols: 30 min of continuous 0.1 Hz stimulation, or 5 min of intermittent 20 Hz stimulation (duty cycle 0.33). Vanadate (500 microM)-treated muscle strips were compared with untreated muscle. Vanadate did not affect force or isometric twitch kinetics of otherwise quiescent muscle. During prolonged 0.1 Hz stimulation, force of control muscles declined by 17 +/- 4% over 30 min, whereas muscles incubated with vanadate maintained force virtually unchanged. Force over time was significantly greater with than without vanadate (P = 0.03), with values being significantly different during the last 10 min of the 30 min stimulation period. In the absence of vanadate force declined at a rate of approximately 0.6% per min, whereas with vanadate the rate of force decline was less than 0.1% per min (P < 0.02). During intermittent 20 Hz stimulation, the degree of force decline was not affected by vanadate at any time over a course of 5 min. Isometric contractile kinetics were not altered by vanadate during either 0.1 or 20 Hz stimulation. These data suggest that vanadate ameliorates low- but not higher-frequency fatigue in diaphragm, suggesting a role for protein tyrosine phosphorylation in the regulation of muscle fatigue resistance.
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Affiliation(s)
- E van Lunteren
- Case Western Reserve University, Cleveland, OH 44106, USA.
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32
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Pariente JA, Lajas AI, Pozo MJ, Camello PJ, Salido GM. Oxidizing effects of vanadate on calcium mobilization and amylase release in rat pancreatic acinar cells. Biochem Pharmacol 1999; 58:77-84. [PMID: 10403521 DOI: 10.1016/s0006-2952(99)00050-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The effects of vanadate were examined by monitoring intracellular free calcium concentration ([Ca2+]i) and amylase secretion in collagenase-dispersed rat pancreatic acinar cells. Vanadate increased [Ca2+]i by mobilizing calcium from agonist-releasable intracellular calcium stores, since this increase was observed in the absence of extracellular calcium and vanadate failed to increase [Ca2+]i after treatment with thapsigargin in calcium-free medium. Moreover, pretreatment of acinar cells with vanadate prevented the cholecystokinin octapeptide (CCK-8)-induced signal of [Ca2+]i, whereas co-incubation with CCK-8 potentiated the plateau phase of calcium response to CCK-8 without modifying the transient calcium spike. The effects of vanadate on calcium mobilization were reversed by the presence of the sulfhydryl reducing agent dithiothreitol. Vanadate also activated the calcium influx, since an additional enhancement of calcium influx induced by thapsigargin-evoked intracellular store depletion was observed and vanadate reversed the inhibitory effect of lanthanum (an inhibitor of calcium entry) into acinar cells. In addition, vanadate evoked a concentration-dependent release of amylase from pancreatic acinar cells and moreover, reduced the secretory response to CCK-8. We conclude that, in pancreatic acinar cells, vanadate releases calcium from the agonist-releasable intracellular calcium pool and consequently induces amylase secretion. These effects are likely due to the oxidizing effects of this compound.
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Affiliation(s)
- J A Pariente
- Department of Physiology, Faculty of Veterinary Sciences, University of Extremadura, Cáceres, Spain.
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33
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Garcia JG, Verin AD, Schaphorst K, Siddiqui R, Patterson CE, Csortos C, Natarajan V. Regulation of endothelial cell myosin light chain kinase by Rho, cortactin, and p60(src). THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:L989-98. [PMID: 10362724 DOI: 10.1152/ajplung.1999.276.6.l989] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Inflammatory diseases of the lung are characterized by increases in vascular permeability and enhanced leukocyte infiltration, reflecting compromise of the endothelial cell (EC) barrier. We examined potential molecular mechanisms that underlie these alterations and assessed the effects of diperoxovanadate (DPV), a potent tyrosine kinase activator and phosphatase inhibitor, on EC contractile events. Confocal immunofluorescent microscopy confirmed dramatic increases in stress-fiber formation and colocalization of EC myosin light chain (MLC) kinase (MLCK) with the actin cytoskeleton, findings consistent with activation of the endothelial contractile apparatus. DPV produced significant time-dependent increases in MLC phosphorylation that were significantly attenuated but not abolished by EC MLCK inhibition with KT-5926. Pretreatment with the Rho GTPase-inhibitory C3 exotoxin completely abolished DPV-induced MLC phosphorylation, consistent with Rho-mediated MLC phosphatase inhibition and novel regulation of EC MLCK activity. Immunoprecipitation of EC MLCK after DPV challenge revealed dramatic time-dependent tyrosine phosphorylation of the kinase in association with increased MLCK activity and a stable association of MLCK with the p85 actin-binding protein cortactin and p60(src). Translocation of immunoreactive cortactin from the cytosol to the cytoskeleton was noted after DPV in concert with cortactin tyrosine phosphorylation. These studies indicate that DPV activates the endothelial contractile apparatus in a Rho GTPase-dependent fashion and suggests that p60(src)-induced tyrosine phosphorylation of MLCK and cortactin may be important features of contractile complex assembly.
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Affiliation(s)
- J G Garcia
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21224, USA.
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34
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Somlyo AP, Wu X, Walker LA, Somlyo AV. Pharmacomechanical coupling: the role of calcium, G-proteins, kinases and phosphatases. Rev Physiol Biochem Pharmacol 1999; 134:201-34. [PMID: 10087910 DOI: 10.1007/3-540-64753-8_5] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The concept of pharmacomechanical coupling, introduced 30 years ago to account for physiological mechanisms that can regulate contraction of smooth muscle independently of the membrane potential, has since been transformed from a definition into what we now recognize as a complex of well-defined, molecular mechanisms. The release of Ca2+ from the SR by a chemical messenger, InsP3, is well known to be initiated not by depolarization, but by agonist-receptor interaction. Furthermore, this G-protein-coupled phosphatidylinositol cascade, one of many processes covered by the umbrella of pharmacomechanical coupling, is part of complex and general signal transduction mechanisms also operating in many non-muscle cells of diverse organisms. It is also clear that, although the major contractile regulatory mechanism of smooth muscle, phosphorylation/dephosphorylation of MLC20, is [Ca2+]-dependent, the activity of both the kinase and the phosphatase can also be modulated independently of [Ca2+]i. Sensitization to Ca2+ is attributed to inhibition of SMPP-1M, a process most likely dominated by activation of the monomeric GTP-binding protein RhoA that, in turn, activates Rho-kinase that phosphorylates the regulatory subunit of SMPP-1M and inhibits its myosin phosphatase activity. It is likely that the tonic phase of contraction activated by a variety of excitatory agonists is, at least in part, mediated by this Ca(2+)-sensitizing mechanism. Desensitization to Ca2+ can occur either through inhibitory phosphorylation of MLCK by other kinases or autophosphorylation and by activation of SMPP-1M by cyclic nucleotide-activated kinases, probably involving phosphorylation of a phosphatase activator. Based on our current understanding of the complexity of the many cross-talking signal transduction mechanisms that operate in cells, it is likely that, in the future, our current concepts will be refined, additional mechanisms of pharmacomechanical coupling will be recognized, and those contributing to the pathologenesis diseases, such as hypertension and asthma, will be identified.
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Affiliation(s)
- A P Somlyo
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville 22906-0011, USA
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35
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Shi S, Verin AD, Schaphorst KL, Gilbert-McClain LI, Patterson CE, Irwin RP, Natarajan V, Garcia JG. Role of tyrosine phosphorylation in thrombin-induced endothelial cell contraction and barrier function. ENDOTHELIUM : JOURNAL OF ENDOTHELIAL CELL RESEARCH 1999; 6:153-71. [PMID: 9930649 DOI: 10.3109/10623329809072202] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Thrombin-induced endothelial cell (EC) barrier dysfunction is highly dependent upon phosphorylation of serine and threonine residues present on myosin light chains (MLC) catalyzed by a novel EC myosin light chain kinase (MLCK) isoform. In this study, we examined the participation of tyrosine protein phosphorylation in EC contraction, gap formation and barrier dysfunction. We first determined that thrombin significantly increases protein tyrosine kinase activity and protein tyrosine phosphorylation in bovine pulmonary artery EC. Tyrosine kinase inhibitors, genistein and 2,5 DHC, reduced EC tyrosine kinase activities, however, only genistein significantly attenuated thrombin-mediated increases in albumin clearance and reductions in transendothelial electrical resistance. Similarly, genistein but not 2,5 DHC, decreased basal and thrombin-induced Ca2+ increases and MLC phosphorylation in the absence of alterations in Type 1 or 2A serine/threonine phosphatase activities. Immunoprecipitation of the EC MLCK isoform revealed a 214 kD immunoreactive phosphotyrosine protein and genistein pretreatment significantly reduced MLCK activity in MLCK immunoprecipitates. Although thrombin induced the translocation of p60src from the cytosol to the EC cytoskeleton, a detectable increase in the level of MLCK tyrosine phosphorylation was not noted after thrombin challenge. Taken together, our data suggest that genistein-sensitive tyrosine kinase activities are involved in thrombin-mediated EC MLCK activation, MLC phosphorylation, and barrier dysfunction.
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Affiliation(s)
- S Shi
- Department of Medicine, Indiana University School of Medicine Richard Roudebush Veterans Administration Center, Indianapolis 46202, USA
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36
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Parfenova H, Fedinec A, Leffler CW. Role of tyrosine phosphorylation in the regulation of cerebral vascular tone in newborn pig in vivo. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:H185-93. [PMID: 9887032 DOI: 10.1152/ajpheart.1999.276.1.h185] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The role of tyrosine phosphorylation was investigated using protein tyrosine phosphatase inhibitors in newborn pigs equipped with a cranial window in vivo. We tested the hypothesis that cyclooxygenase and nitric oxide (NO) synthase are physiological targets for tyrosine phosphorylation in cerebral circulation. Phenylarsine oxide dilated pial arterioles and increased prostacyclin and prostaglandin E2 in cortical periarachnoid fluid; these responses were inhibited by indomethacin. Nomega-nitro-L-arginine methyl ester (L-NAME) and Nomega-nitro-L-arginine (L-NNA) inhibited the vasodilation to phenylarsine oxide; the effects of NO synthase inhibitors and indomethacin were additive. Cyclooxygenase-mediated vascular responses were assessed using topical application of arachidonic acid. Phenylarsine oxide and sodium orthovanadata potentiated vasodilation and prostanoid synthesis in response to arachidonic acid. Nomega-nitro-L-arginine methyl ester and Nomega-nitrol-arginine did not affect vasodilation or prostanoid production in response to arachidonic acid, indicating no cross talk between cyclooxygenase and NO synthase. These data indicate that cyclooxygenase and NO synthase are physiological targets for tyrosine phosphorylation in the cerebral circulation of newborn pigs.
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Affiliation(s)
- H Parfenova
- Laboratory for Research in Neonatal Physiology, Department of Physiology, University of Tennessee, Memphis, Tennessee 38163, USA
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37
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Hughes AD, Wijetunge S. Role of tyrosine phosphorylation in excitation-contraction coupling in vascular smooth muscle. ACTA PHYSIOLOGICA SCANDINAVICA 1998; 164:457-69. [PMID: 9887969 DOI: 10.1046/j.1365-201x.1998.00446.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Increasingly it is recognized that tyrosine phosphorylation plays an important part in the regulation of function in differentiated contractile vascular smooth muscle. Tyrosine kinases and phosphatases are present in large amounts in vascular smooth muscle and have been reported to influence a number of processes crucial to contraction, including ion channel gating, calcium homeostasis and sensitization of the contractile process to [Ca2+]i. This review summarizes current understanding regarding the role of tyrosine phosphorylation in excitation-contraction coupling in blood vessels.
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Affiliation(s)
- A D Hughes
- National Heart and Lung Institute, Imperial College of Science, Technology and Medicine, St Mary's Hospital, London, UK
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38
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Yousufzai SY, Abdel-Latif AA. Tyrosine kinase inhibitors suppress prostaglandin F2alpha-induced phosphoinositide hydrolysis, Ca2+ elevation and contraction in iris sphincter smooth muscle. Eur J Pharmacol 1998; 360:185-93. [PMID: 9851585 DOI: 10.1016/s0014-2999(98)00697-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We investigated the effects of the protein tyrosine kinase inhibitors, genistein, tyrphostin 47, and herbimycin on prostaglandin F2alpha- and carbachol-induced inositol-1,4,5-trisphosphate (IP3) production, [Ca2+]i mobilization and contraction in cat iris sphincter smooth muscle. Prostaglandin F2alpha and carbachol induced contraction in a concentration-dependent manner with EC50 values of 0.92 x 10(-9) and 1.75 x 10(-8) M, respectively. The protein tyrosine kinase inhibitors blocked the stimulatory effects of prostaglandin F2alpha, but not those evoked by carbachol, on IP3 accumulation, [Ca2+]i mobilization and contraction, suggesting involvement of protein tyrosine kinase activity in the physiological actions of the prostaglandin. Daidzein and tyrphostin A, inactive negative control compounds for genistein and tyrphostin 47, respectively, were without effect. Latanoprost, a prostaglandin F2alpha analog used as an antiglaucoma drug, induced contraction and this effect was blocked by genistein. Genistein (10 microM) markedly reduced (by 67%) prostaglandin F2alpha-stimulated increase in [Ca2+]i but had little effect on that of carbachol in cat iris sphincter smooth muscle cells. Vanadate, a potent inhibitor of protein tyrosine phosphatase, induced a slow gradual muscle contraction in a concentration-dependent manner with an EC50 of 82 microM and increased IP3 generation in a concentration-dependent manner with an EC50 of 90 microM. The effects of vanadate were abolished by genistein (10 microM). Wortmannin, a myosin light chain kinase inhibitor, reduced prostaglandin F2alpha- and carbachol-induced contraction, suggesting that the involvement of protein tyrosine kinase activity may lie upstream of the increases in [Ca2+]i evoked by prostaglandin F2alpha. Further studies aimed at elucidating the role of protein tyrosine kinase activity in the coupling mechanism between prostaglandin F2alpha receptor activation and increases in intracellular Ca2+ mobilization and identifying the tyrosine-phosphorylated substrates will provide important information about the role of protein tyrosine kinase in the mechanism of smooth muscle contraction, as well as about the mechanism of the intraocular pressure lowering effect of the prostaglandin in glaucoma patients.
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Affiliation(s)
- S Y Yousufzai
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta 30912, USA
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39
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Furspan PB, Freedman RR. Effect of modulators of protein tyrosine kinase activity on gender-related differences in vascular reactivity at reduced temperature. J Cardiovasc Pharmacol 1998; 32:728-35. [PMID: 9821846 DOI: 10.1097/00005344-199811000-00008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We used the isolated-muscle-bath technique to examine the effect of protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP) inhibitors on the response of rings of tail artery from male and female rats to cooling and reduced temperature in the absence and presence of two PTK-dependent (clonidine and serotonin) and one PTK-independent (phenylephrine, PE) agonists. At 37 degrees C, reactivity to clonidine, serotonin, and PE was the same in tail artery from female and male rats. At 25 degrees C, reactivity to clonidine and serotonin, but not PE, was greater in tail artery from female rats compared with those from male rats. Sodium orthovanadate (SOV) eliminated the gender-related difference in the contractile effect of clonidine and serotonin at 25 degrees C. The sensitivity to relaxation by genistein was considerably greater for clonidine and serotonin at both temperatures as compared with PE. At 25 degrees C the sensitivity to genistein was greater for the clonidine and serotonin-contracted rings from female rats. In the presence of SOV, temperature reduction led to contraction of rat-tail artery. This effect was greater in rings from female rats. Our results strongly implicate differences in the activity of the PTK transduction pathway as the cause of the observed gender-related differences in agonist-mediated contraction at 25 degrees C and in cold-induced vasoconstriction.
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Affiliation(s)
- P B Furspan
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, USA
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40
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Uzun O, Demiryürek AT, Kanzik I. The role of tyrosine kinase in hypoxic constriction of sheep pulmonary artery rings. Eur J Pharmacol 1998; 358:41-7. [PMID: 9809867 DOI: 10.1016/s0014-2999(98)00592-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Complex and incompletely understood mechanisms underline the vascular responses to hypoxia. Recent studies showed that the tyrosine kinase pathway is involved in vasoconstriction of vascular smooth muscle. Therefore, the aim of this study was to determine the tyrosine kinase pathway for the hypoxic contraction in large-diameter sheep pulmonary artery rings in vitro by studying the effects of selective inhibitors of tyrosine kinase and of a protein tyrosine kinase inhibitor. Lowering the pO2 from 96 to 5 mm Hg caused a contraction in arteries precontracted with 5-hydroxytryptamine (5-HT) but not under resting force. Preincubation of arteries with the tyrosine kinase inhibitors, genistein and tyrphostin, abolished the hypoxic contraction without affecting 5-HT contractions. Inhibition of tyrosine phosphatase activity by sodium orthovanadate increased the hypoxic vasoconstriction in 5-HT-precontracted arteries. These results suggest that the tyrosine kinase pathway is involved in hypoxic pulmonary vasoconstriction in sheep isolated pulmonary artery rings.
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Affiliation(s)
- O Uzun
- Department of Pharmacology, Faculty of Pharmacy, Gazi University, Etiler, Ankara, Turkey
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41
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Sim SS, Kim CJ. The involvement of protein kinase C and tyrosine kinase in vanadate-induced contraction. Arch Pharm Res 1998; 21:315-9. [PMID: 9875450 DOI: 10.1007/bf02975294] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Gastric smooth muscle of cats was used to investigate the involvement of protein kinase in vanadate-induced contraction. Vanadate caused a contraction of cat gastric smooth muscle in a dose-dependent manner. Vanadate-induced contraction was totally inhibited by 2 mM EGTA and 1.5 mM LaCl3 and significantly inhibited by 10 microM verapamil and 1 microM nifedipine, suggesting that vanadate-induced contraction is dependent on the extracellular Ca2+ concentration. and the influx of extracellular Ca2+ was mediated through voltage-dependent Ca2+ channel. Both protein kinase C inhibitor and tyrosine kinase inhibitor significantly inhibited the vanadate-induced contraction and the combined inhibitory effect of two protein kinase inhibitors was greater than that of each one. But calmodulin antagonists did not have any influence on the vanadate-induced contraction. On the other hand, both forskolin (1 microM) and sodium nitroprusside (1 microM) significantly inhibited vanadate-induced contraction. Therefore, these results suggest that both protein kinase C and tyrosine kinase are involved in the vanadate-induced contraction which required the influx of extracellular Ca2+ in cat gastric smooth muscle, and that the contractile mechanism of vanadate may be different from that of agonist binding to its specific receptor.
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Affiliation(s)
- S S Sim
- Department of Pathophysiology, College of Pharmacy, Chung-Ang University, Seoul, Korea
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42
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Wijetunge S, Lymn JS, Hughes AD. Effect of inhibition of tyrosine phosphatases on voltage-operated calcium channel currents in rabbit isolated ear artery cells. Br J Pharmacol 1998; 124:307-16. [PMID: 9641547 PMCID: PMC1565393 DOI: 10.1038/sj.bjp.0701840] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
1. The effect of increasing cellular tyrosine phosphorylation by inhibiting endogenous tyrosine phosphatases was examined on voltage-operated calcium channel currents in vascular smooth muscle cells. 2. In single ear artery smooth muscle cells of the rabbit, studied by the whole cell voltage clamp technique, intracellular application of the tyrosine phosphatase inhibitors, sodium orthovanadate (100 microM) and peroxyvanadate (100 microM orthovanadate + 1 mM H2O2) increased voltage-operated calcium channel currents by 56% and 83%, respectively. 3. Bath application of two other membrane permeant tyrosine phosphatase inhibitors, phenylarsine oxide (100 microM) and dephostatin (50 microM) also increased voltage-operated calcium channel currents by 48% and 52%, respectively. 4. The selective tyrosine kinase inhibitor, tyrphostin-23 (100 microM) reduced calcium channel currents by 41%. Pre-incubation with tyrphostin-23 abolished the effects of peroxyvanadate, phenylarsine oxide and dephostatin on calcium channels. 5. Western blot analysis of rabbit ear artery cell lysates showed increased tyrosine phosphorylation of several endogenous proteins following treatment with peroxyvanadate. 6. These results indicate that a number of structurally dissimilar inhibitors of tyrosine phosphatases increase voltage-operated calcium channel currents in arterial smooth muscle cells presumably due to increased tyrosine phosphorylation.
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Affiliation(s)
- S Wijetunge
- Clinical and Cardiovascular Pharmacology, NHLI, Imperial College School of Medicine, St. Mary's Hospital, London
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43
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Sagher O, Huang DL, Webb RC. Induction of hypercontractility in human cerebral arteries by rewarming following hypothermia: a possible role for tyrosine kinase. J Neurosurg 1997; 87:431-5. [PMID: 9285610 DOI: 10.3171/jns.1997.87.3.0431] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Induction of hypothermia is used routinely in neurosurgical and cardiovascular operations to protect the brain from ischemic insult. However, despite a plethora of experimental evidence supporting the use of hypothermia to protect the brain from ischemia, clinical experience using deliberate hypothermia in humans has not shown a convincing benefit. The authors tested the hypothesis that hypothermia and rewarming alter tone in human cerebral vessels and may interfere with cerebral perfusion in the setting of deliberate hypothermia. They examined human cerebral arteries during hypothermia (32 degrees C and 17 degrees C) and during rewarming to delineate the direct effects of cooling and rewarming on cerebrovascular tone. Artery segments obtained from autopsy material and from specimens excised at elective temporal lobectomies were tested in tissue baths using isometric tension measurements. Temperature-induced changes in vascular tone were measured and quantified with respect to contractile responses to serotonin (5-HT; 10(-6) M). Cooling induced mild relaxation in cerebral vessels (-38 +/- 12% 5-HT response in 50 vessels from autopsy specimens, -69 +/- 10% 5-HT response in 51 vessels from lobectomy specimens). On rewarming, vessels contracted significantly beyond their baseline tone (108 +/- 18% 5-HT response in 50 vessels from autopsy specimens, 42 +/- 12% 5-HT response in 51 vessels from lobectomy specimens). Rewarming-induced hypercontractility was inhibited by the tyrosine kinase inhibitor genistein (-5 +/- 7% vs. 70 +/- 23% 5-HT response, genistein vs. control, 14 segments, p < 0.05) and enhanced by the tyrosine phosphatase inhibitor sodium orthovanadate (339 +/- 54% vs. 104 +/- 20% 5-HT response, sodium orthovanadate vs. control, five segments, p < 0.05), indicating a possible role for tyrosine kinase activation in the rewarming-induced contraction.
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Affiliation(s)
- O Sagher
- Department of Physiology, University of Michigan Medical Center, Ann Arbor 48109, USA
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Nelson SR, Chien T, Di Salvo J. Genistein sensitivity of calcium transport pathways in serotonin-activated vascular smooth muscle cells. Arch Biochem Biophys 1997; 345:65-72. [PMID: 9281312 DOI: 10.1006/abbi.1997.0247] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Recent studies showed that serotonin-activated increases in intracellular Ca2+ in vascular smooth muscle cells are associated with enhanced protein tyrosine phosphorylation. These responses were blocked by inhibition of tyrosine kinase activity with genistein, suggesting that the increases in Ca2+ and tyrosine phosphorylation are functionally coupled. Therefore, we sought to characterize genistein-sensitive Ca2+ transport pathways in rat aortic A10 cells loaded with fura-2. In the presence of extracellular Ca2+, serotonin evoked a transient increase in [Ca2+]i that was followed by a smaller sustained increase. The transient was inhibited 25-40% by L-type Ca2+ channel antagonists and inhibited 90-95% by genistein. The sustained response was unaffected by L-channel antagonists and only slightly inhibited by genistein. In the absence of extracellular Ca2+, the transient was reduced by 50%, while the sustained component was virtually abolished. These results suggest that influx and release pathways are major contributors to the transient component, whereas the lower sustained component is largely limited to influx pathways. The influx pathway during the transient probably involves an L-type Ca2+ channel that is regulated by tyrosine kinase activity. The pathways that participate in the sustained response are different because they are insensitive to l-channel antagonists and only slightly inhibited by genistein. The transient evoked in Ca2+-free media was blocked by genistein, inhibited by caffeine, and prevented by thapsigargin. Ionomycin-induced release of Ca2+ was unaffected by genistein, reduced by caffeine, and essentially eliminated by thapsigargin. Therefore, thapsigargin-mediated suppression of serotonin-activated release probably reflects depletion of Ca2+ from the sarcoplasmic reticulum, whereas genistein-mediated suppression probably reflects inhibition of tyrosine kinase linked release. Caffeine-mediated suppression appears to involve both partial depletion of Ca2+ and interference with release. Each A10 cell expressed at least two different ryanodine receptors and two different receptors for inositol 1,4,5-trisphosphate.
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Affiliation(s)
- S R Nelson
- Department of Physiology, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Abstract
The mechanism of contractile effect of vanadate was investigated in rat aortae. Sodium metavanadate (NaVO3; 10(-5)-3 x 10(-3) M) induced contractile responses in a concentration-dependent manner. Removal of endothelium did not affect the response to NaVO3. The response to NaVO3 was inhibited by nifedipine, a voltage-operated Ca2+ channel (VOC) inhibitor; NCDC, a phospholipase C inhibitor; and H-7, a protein kinase C inhibitor, but not by prazosin, an alpha1-adrenoceptor antagonist; methysergide, a serotonin-receptor antagonist; tripelennamine, a histamine-receptor antagonist; glibenclamide, an adenosine triphosphate (ATP)-dependent K+-channel inhibitor; or iberiotoxin, a large-conductance Ca2+-activated K+-channel inhibitor. In addition, genistein or tyrphostin A48, tyrosine kinase inhibitors, did not affect the contraction induced by NaVO3. Mg2+ removal or antimycin A, a Ca2+-ATPase inhibitor, did not cause any contraction. Ouabain, a Na+, K+-ATPase inhibitor, or K+-free medium caused the contraction of the aortae. The maximal contraction induced by NaVO3 plus ouabain was similar to that induced by NaVO3 alone. In addition, the response to NaVO3 was inhibited by AA861, a 5-lipoxygenase inhibitor, and RHC-80267, a diacylglycerol (DAG) lipase inhibitor. In the presence of AA861, either H-7 or nifedipine further inhibited the residual response to NaVO3. In the presence of NCDC, however, AA861 failed further to affect the residual response to NaVO3. In rat aortae, NaVO3 increased the levels of inositol monophosphate (IP) and prostaglandin F2alpha (PGF2alpha). AA861 and NCDC inhibited the IP increase. In addition, NCDC inhibited the PGF2alpha increase. These results suggest that the response to NaVO3 in rat aortae may be mainly the result of the increased phosphoinositide metabolism.
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Affiliation(s)
- Q Zhou
- Department of Pharmacology, School of Medicine, University of Hawaii, Honolulu 96822, U.S.A
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Venkataraman BV, Ravishankar HN, Rao AV, Kalyani P, Sharada G, Namboodiri K, Gabor B, Ramasarma T. Decavanadate possesses alpha-adrenergic agonist activity and a structural motif common with trans-beta form of noradrenaline. Mol Cell Biochem 1997; 169:27-36. [PMID: 9089628 DOI: 10.1023/a:1006882408983] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Decavanadate, an inorganic polymer of vanadate, produced contraction of rat aortic rings at a relatively high concentration compared to phenylephrine, an agonist of alpha-adrenergic receptor. This effect was blocked by two known alpha-adrenergic receptor antagonists, prazosin and phenoxybenzamine. Decavanadate, formed by possible dimerization of V5 under acid conditions, possessed a structural feature of two pairs of unshared oxygen atoms at a distance of 3.12 A, not found in its constituents of V4 or V5. A structural motif of O..O..O using such oxygen atoms is recognized in decavanadate. This matches with a similar motif of N..O..O that uses the essential amino and hydroxyl groups of the side-chain and the m-hydroxyl group in trans-beta form of noradrenaline. The interaction of such a structural motif with the membrane receptor is likely to be the basis of the unusual noradrenaline-mimic action of decavanadate.
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Affiliation(s)
- B V Venkataraman
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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Ohanian J, Ohanian V, Shaw L, Bruce C, Heagerty AM. Involvement of tyrosine phosphorylation in endothelin-1-induced calcium-sensitization in rat small mesenteric arteries. Br J Pharmacol 1997; 120:653-61. [PMID: 9051304 PMCID: PMC1564509 DOI: 10.1038/sj.bjp.0700950] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
1. We have studied the effect of endothelin-1 stimulation on protein tyrosine phosphorylation levels in intact small mesenteric arteries of the rat and investigated the effects of tyrosine kinase inhibition on the contractile response to this agonist. 2. Endothelin-1 stimulated a rapid (20 s), sustained (up to 20 min) and concentration-dependent (1-100 nM) increase in protein tyrosine phosphorylation levels which coincided temporally with the contractile response in intact and alpha-toxin permeabilized small artery preparations. Tyrosine phosphorylation was increased in four main clusters of proteins of apparent molecular mass 28-33, 56-61, 75-85 and 105-115 kDa. Endothelin-1-induced protein tyrosine phosphorylation was independent of extracellular calcium, antagonized by the tyrosine kinase inhibitor tyrphostin A23 but not by the inactive tyrphostin A1. 3. In intact small arteries tyrphostin A23 inhibited the force developed to endothelin-1 at all concentrations studied; at higher concentrations (10 and 100 nM) the profile of contraction was altered from a sustained to a transient response. Tyrphostin A1 inhibited the contractile response to endothelin-1 at all concentrations except 100 nM; the profile of the response was not altered. Neither tyrphostin affected the transient phasic contraction induced by endothelin-1 (100 nM) in the absence of extracellular calcium. 4. In rat alpha-toxin permeabilized mesenteric arteries endothelin-1 caused a concentration-dependent increase in force in the presence of 10 microM GTP and low (pCa 6.7) constant calcium, demonstrating increased sensitivity of the contractile apparatus to calcium. Tyrphostin A23 inhibited this response by approximately 50%, tyrphostin A1 did not affect endothelin-1-induced calcium sensitization of force. 5. We conclude that increased tyrosine phosphorylation is important in the contractile response induced by endothelin-1 in intact small mesenteric arteries. Furthermore our data implicate activation of this signalling pathway in the tonic phase of contraction possibly through modulation of the sensitivity of the contractile apparatus to calcium.
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Affiliation(s)
- J Ohanian
- Department of Medicine, Manchester Royal Infirmary
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Ziegler RJ. HIV-1 gp120 Effects on Signal Transduction Processes and Cytokines: Increased src-Family Protein Tyrosine Kinase Activity. ACTA ACUST UNITED AC 1997; 1:51-71. [PMID: 16873171 DOI: 10.1300/j128v01n03_04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Varying degrees of neurological dysfunction are observed in AIDS patients who develop AIDS dementia complex (ADC). Data from a large number of in vivo and in vitro rodent studies have suggested a role for the HIV envelope glycoprotein gp 120 in this process. These studies were initiated to clarify possible effects of recombinant gp120 on signal transduction systems and the synthesis of specific ADC-related cytokines in human neuroblastoma cells. Out results indicate that gp120 on signal transduction systems and the synthesis of specific ADC-related cytokines in human neuroblastoma cells. Our results indicate that gp120 did not induce the synthesis of cAMP, IPs or NO, nor did it alter agonist-induced synthesis of these molecules. In addition, it did not induce the synthesis of IL-6 and TNFα. However, it did activate a src-family protein tyrosine kinase which phosphorylates several substrates, including prominent proteins in the 115 and 60 kDa range. This gp120-induced tyrosine phosphorylation may contribute to neurological dysfunction since protein tyrosine kinases are known to be involved in processes important for pre- and post-synaptic neuronal function.
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Perez-Vallina JR, Revuelta MP, Cantabrana B, Hidalgo A. Effect of Rp diastereoisomer of adenosine 3',5' cyclic-monophosphothioate on the cAMP-dependent relaxation of smooth muscle. Life Sci 1997; 61:869-80. [PMID: 9284080 DOI: 10.1016/s0024-3205(97)00589-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effect of Rp diastereoisomer of adenosine 3',5'-cyclic monophosphothioate (Rp-cAMPS) on relaxation elicited by histamine (1-100 microM), forskolin (1-60 microM), papaverine (1-100 microM), vinpocetine (1-100 microM), rolipram (0.1-1 mM), Sp-cAMPS (10-300 microM), 8-BrcAMP (10 microM - 1 mM) and 8-BrcGMP (3 microM - 1 mM) of the previous vanadate-induced contraction was assayed. The effect of Rp-cAMPS on the relaxing effect produced by forskolin, papaverine, vinpocetine, rolipram, Sp-cAMPS and 8-BrcAMP in KCl-induced tonic contraction was also assayed. Histamine, forskolin, papaverine, rolipram, Sp-cAMPS, 8-BrcAMP and 8-BrcGMP, but not vinpocetine, relaxed the vanadate-induced contractions in rat uterus incubated in medium lacking calcium plus EDTA in a concentration-dependent way. Rp-cAMPS (1-300 microM) had no effect on vanadate contraction. However, it antagonized the relaxation elicited by histamine and papaverine, but not that of forskolin, rolipram, Sp-cAMPS, 8-BrcAMP and 8-BrcGMP. Forskolin, papaverine, vinpocetine, rolipram and 8-BrcAMP, but not Sp-cAMPS, relaxed the KCl-induced contraction. Rp-cAMPS antagonized the relaxation elicited by forskolin, papaverine and vinpocetine, but not that of rolipram and 8-BrcAMP. Our results suggest that: a) Rp-cAMPS is an effective PKA inhibitor that could be used to study the involvement of cAMP on drug-induced response in smooth muscle, and b) the effects of Sp-cAMPS, 8-BrcAMP and rolipram were independent of the activation of protein kinases.
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Affiliation(s)
- J R Perez-Vallina
- Laboratorio de Farmacología, Dpto. Medicina, Facultad de Medicina, Oviedo, Spain
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St-Louis J, Sicotte B, Breton E, Srivastava AK. Contractile effects of vanadate on aorta rings from virgin and pregnant rats. Mol Cell Biochem 1995; 153:145-50. [PMID: 8927030 DOI: 10.1007/bf01075930] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The present study was undertaken to characterize the contractile effects of vanadate on thoracic aorta rings from virgin and term-pregnant rats. Vanadate caused concentration-dependent contraction in rat aortic rings with an EC50 (concentration producing 50% maximum response) of 0.10 mM. Contractions in response to vanadate were equivalent to the ones measured with 1 microM phenylephrine. The effects of vanadate were not affected by indomethacin (up to 10 microM), an inhibitor of prostanoid cyclooxygenase, but were blocked in a concentration-dependent manner by staurosporine (0.1-1.0 microM), an inhibitor of protein kinase C. Vanadate exhibited a significant decrease of contractile responses in aorta of pregnant as compared to virgin rats. When aortic rings were bathed in presence of different concentrations of vanadate, the concentration-response curve to phenylephrine was shifted to the left, but maximum response was not affected. The potentiation of the contractions to phenylephrine by vanadate was significantly more prominent in aorta of virgin than of pregnant rats. These results suggest that the contractile effect of vanadate on rat aorta is independent of endogenous prostanoids and may be mediated by protein kinase C-dependent pathway. These results also show that the contractile response to vanadate on the rat aorta is impaired during pregnancy.
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Affiliation(s)
- J St-Louis
- Centre de recherche, Hôpital Ste-Justine, Montréal, Qc, Canada
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