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Alsufyani HA, Docherty JR. Effects of RS17053 on α 1 -adrenoceptors in rat vas deferens and aorta. Fundam Clin Pharmacol 2023; 37:1170-1178. [PMID: 37392126 DOI: 10.1111/fcp.12930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 05/01/2023] [Accepted: 06/07/2023] [Indexed: 07/02/2023]
Abstract
BACKGROUND RS17053 is classed as an α1A -adrenoceptor selective antagonist. OBJECTIVES We have examined its profile of action at all subtypes of α1 -adrenoceptor. METHODS Noradrenaline (NA) evoked contractions of rat vas deferens involve α1D -adrenoceptors in phasic contractions and α1A -adrenoceptors in tonic contractions. Contractions of rat aorta to NA involve α1D - and α1B -adrenoceptors. RESULTS RS17053 (10-5 M) shifted NA potency and virtually abolished tonic contractions to NA, with little or limited effect on phasic contractions. The α1D -adrenoceptor antagonist BMY7378 (3 × 10-7 M) significantly inhibited the remaining phasic component of the contractions, and the α1A -adrenoceptor antagonist RS100329 (10-7 M) inhibited further the residual tonic contraction. Hence, RS17053 shows high selectivity for α1A -adrenoceptors over α1D -adrenoceptors in rat vas deferens. However, RS17053 (10-5 M) produced a large shift in the potency of NA in rat aorta, with a pKB of 6.82. Large shifts of NA potency in rat aorta involve α1B -adrenoceptor blockade. CONCLUSION Results in rat vas deferens demonstrate low potency of RS17053 at α1D -adrenoceptors, but results from rat aorta can only be explained as demonstrating α1B -adrenoceptor antagonism by RS17053. RS17053 may be a useful pharmacological tool when reclassified as a mainly α1A - and to a lesser extent α1B -adrenoceptor antagonist with little effect at α1D -adrenoceptors.
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Affiliation(s)
- Hadeel A Alsufyani
- Department of Physiology, King Abdulaziz University, Jeddah, Saudi Arabia
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin, Ireland
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Alsufyani HA, Docherty JR. Involvement of α 1B-adrenoceptors and Rho kinase in contractions of rat aorta and mouse spleen. Korean J Physiol Pharmacol 2023; 27:325-331. [PMID: 37386830 DOI: 10.4196/kjpp.2023.27.4.325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/15/2022] [Accepted: 07/18/2022] [Indexed: 07/01/2023]
Abstract
α1-adrenoceptors link via the G-protein Gq/G11 to both Ca2+ entry and release from stores, but may also activate Rho kinase, which causes calcium sensitization. This study aimed to identify the subtype(s) of α1-adrenoceptor involved in Rho kinase-mediated responses in both rat aorta and mouse spleen, tissues in which contractions involve multiple subtypes of α1-adrenoceptor. Tissues were contracted with cumulative concentrations of noradrenaline (NA) in 0.5 log unit increments, before and in the presence of an antagonist or vehicle. Contractions produced by NA in rat aorta are entirely α1-adrenoceptor mediated as they are competitively blocked by prazosin. The α1A-adrenoceptor antagonist RS100329 had low potency in rat aorta. The α1D-adrenoceptor antagonist BMY7378 antagonized contractions in rat aorta in a biphasic manner: low concentrations blocking α1D-adrenoceptors and high concentrations blocking α1B-adrenoceptors. The Rho kinase inhibitor fasudil (10 μM) significantly reduced aortic contractions in terms of maximum response, suggesting inhibition of α1B-adrenoceptor mediated responses. In the mouse spleen, a tissue in which all 3 subtypes of α1-adrenoceptor are involved in contractions to NA, fasudil (3 μM) significantly reduced both early and late components to the NA contraction, the early component involving α1B- and α1D-adrenoceptors, and the late component involving α1B- and α1A-adrenoceptors. This suggests that fasudil inhibits α1B-adrenoceptor mediated responses. It is concluded that α1D- and α1B-adrenoceptors interact in rat aorta and α1D-, α1A- and α1B-adrenoceptors interact in the mouse spleen to produce contractions and these interactions suggest that one of the receptors preferentially activates Rho kinase, most likely the α1B-adrenoceptor.
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Affiliation(s)
- Hadeel A Alsufyani
- Department of Physiology, King Abdulaziz University, Jeddah 22254, Saudi Arabia
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin 2, D02 YN77, Ireland
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Ingrande J, Patel HH, Kendall D, Stefanska B, Alexander S, Bakhle M, Cirino G, Docherty JR, George CH, Insel PA, Ji Y, King BF, Lilley E, Panettieri RA, Ramage AG, Sobey CG, Stanford SC, Stephens G, Teixeira M, Vergnolle N, Ahluwalia A. Guidance for the use and reporting of anaesthetic agents in BJP manuscripts involving work with animals. Br J Pharmacol 2023; 180:255-263. [PMID: 36529953 DOI: 10.1111/bph.15992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Scientists who plan to publish in the British Journal of Pharmacology (BJP) should read this article before undertaking studies utilising anaesthetics in mammalian animals. This editorial identifies certain gaps in the reporting of details on the use of anaesthetics in animal research studies published in the BJP. The editorial also provides guidance, based upon current best practices, for performing in vivo experiments that require anaesthesia. In addition, mechanisms of action and physiological impact of specific anaesthetic agents are discussed. Our goal is to identify best practices and to provide guidance on the information required for manuscripts submitted to the BJP that involve the use of anaesthetic agents in studies with experimental animals.
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Affiliation(s)
- Jerry Ingrande
- VA San Diego Healthcare System and University of California, San Diego, California, USA
| | - Hemal H Patel
- VA San Diego Healthcare System and University of California, San Diego, California, USA
| | | | | | | | | | | | | | | | - Paul A Insel
- University of California, San Diego, California, USA
| | - Yong Ji
- Nanjing Medical University, Nanjing, China
| | | | | | | | | | | | | | | | - Mauro Teixeira
- Federal University of Minas Gerais, Belo Horizonte, Brazil
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Docherty JR, Alsufyani HA. Effects of the Rho Kinase Inhibitor Fasudil on Adrenergic Contractions of Rat Aorta and Mouse Spleen. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.l8054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Alsufyani HA, Docherty JR. Roles for α 1-adrenoceptors during contractions by electrical field stimulation in mouse vas deferens. Korean J Physiol Pharmacol 2021; 25:525-532. [PMID: 34697263 PMCID: PMC8552829 DOI: 10.4196/kjpp.2021.25.6.525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/01/2021] [Accepted: 06/01/2021] [Indexed: 11/15/2022]
Abstract
We have investigated the relative roles of α1-adrenoceptors and purinoceptors in contractions to low and high frequency stimulation of the mouse vas deferens, in terms of the time course of responses. In separate experiments, isometric contractile responses were obtained to 10 pulses at 1 Hz and 40 pulses at 10 Hz. Responses to 1 Hz stimulation consisted of a series of discrete peaks. The α1A-adrenoceptor antagonist RS100329 (10–9M–10–7M) significantly reduced the response to the first pulse, the α1D-adrenoceptor antagonist BMY7378 (10–7M–10–6M) significantly reduced the response to the first two pulses, and the non-selective α1-adrenoceptor antagonist prazosin (10–8M) reduced the response to the first 4 pulses at 1 Hz. Responses to 10 Hz stimulation consisted of an early peak response and a maintained plateau response. RS100329 significantly reduced the peak response but did not significantly affect the plateau response. Prazosin, significantly reduced both the peak and plateau responses. The α1A-adrenoceptor antagonist RS17053 in high concentrations reduced mainly the plateau response leaving a clear early peak response. The plateau response of contraction was almost abolished by the purinoceptor antagonist suramin. These results suggest that there is a relatively minor early α1D-adrenoceptor and a larger early α1A-adrenoceptor component to stimulation-evoked contractions of mouse vas deferens, but the major α1-adrenoceptor component is revealed by prazosin to be α1B-adrenoceptor mediated. α1B-Adrenoceptor activation probably facilitates contractions mediated by other α1-adrenoceptors and by purinoceptors. These results suggest that combined non-selective α1-adrenoceptor blockade, particularly α1B-adrenoceptor blockade, in addition to P2X1-purinoceptor blockade is useful in reducing male fertility.
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Affiliation(s)
- Hadeel A. Alsufyani
- Department of Physiology, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - James R. Docherty
- Department of Physiology, Royal College of Surgeons in Ireland (RCSI), Dublin D02 YN77, Ireland
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Abstract
Psychostimulant, cardiovascular, and temperature actions of stimulants involve adrenergic (norepinephrine), dopaminergic (dopamine), and serotonergic (serotonin) pathways. Stimulants such as amphetamine, 3,4-methylenedioxymethamphetamine (MDMA), or mephedrone can act on the neuronal membrane monoamine transporters NET, DAT, and SERT and/or the vesicular monoamine transporter 2 to inhibit reuptake of neurotransmitter or cause release by reverse transport. Stimulants may have additional effects involving pre- and postsynaptic/junctional receptors for norepinephrine, dopamine, and serotonin and other receptors. As a result, stimulants may have a wide range of possible actions. Agents with cocaine or MDMA-like actions can induce serious and potentially fatal adverse events via thermodysregulatory, cardiovascular, or other mechanisms. MDMA-like stimulants may cause hyperthermia that can be life threathening. Recreational users of stimulants should be aware of the dangers of hyperthermia in a rave/club environment.
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Affiliation(s)
| | - Hadeel A Alsufyani
- Department of Physiology, King Abdulaziz University, Jeddah, Saudi Arabia
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Alsufyani HA, Daly C, Docherty JR. Interaction between α 1B - and other α 1 - and α 2 -adrenoceptors in producing contractions of mouse spleen. Basic Clin Pharmacol Toxicol 2021; 129:416-426. [PMID: 34383990 DOI: 10.1111/bcpt.13639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 07/24/2021] [Accepted: 08/02/2021] [Indexed: 11/30/2022]
Abstract
We have investigated the interaction of α1 - and α2 -adrenoceptor subtypes in producing isometric contractions to NA in mouse whole spleen. The α1 -adrenoceptor antagonist prazosin (10-8 M) or the α2 -adrenoceptor antagonist yohimbine (10-6 M) alone produced only small shifts in NA potency in wild type (WT) mice, but the combination produced a large shift in NA potency. In spleen from α1A/D -KO mice, the effects of prazosin and the combination of prazosin and yohimbine were similar to their effects in WT mice. Hence, in α1A/D -KO mice, in which the only α1 -adrenoceptor present is the α1B -adrenoceptor, prazosin still antagonized contractions to NA. The α1A -adrenoceptor antagonist RS100329 (3x10-9 M) produced significant shifts in the effects of higher concentrations of NA (EC50 and EC75 levels) and the α1D -adrenoceptor antagonist BMY7378 (3x10-8 M) produced significant shifts in the effects of lower concentrations of NA (EC25 and EC50 levels). The effects of BMY7378 and RS00329 demonstrate α1D -adrenoceptor and α1A -adrenoceptor components, and suggest that the α1B -adrenoceptor interacts with an α1D -adrenoceptor, and to a lesser extent an α1A -adrenoceptor, at low, and an α1A -adrenoceptor at high, NA concentrations. This study demonstrates the complex interaction between α1 - and α2 -adrenoceptor subtypes in producing contractions of mouse spleen and may have general implications for α-adrenoceptor mediated control of smooth muscle.
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Affiliation(s)
- Hadeel A Alsufyani
- Department of Physiology, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Craig Daly
- School of Life Sciences, University of Glasgow, Glasgow, Scotland
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McCormick PA, Higgins M, McCormick CA, Nolan N, Docherty JR. Hepatic infarction, hematoma, and rupture in HELLP syndrome: support for a vasospastic hypothesis. J Matern Fetal Neonatal Med 2021; 35:7942-7947. [PMID: 34130599 DOI: 10.1080/14767058.2021.1939299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Purpose: HELLP syndrome is a relatively uncommon pregnancy-related condition characterized by hemolysis, elevated liver function tests, and low platelets. It can be accompanied by life-threatening hepatic complications including hepatic infarction, hematoma formation, and hepatic rupture. HELLP syndrome occurs in approximately 0.2% of pregnancies. Major hepatic complications occur in less than 1% of HELLP patients suggesting an incidence of 1/50,000. The pathogenesis is incompletely understood and in particular, it is difficult to understand a disorder with both major thrombotic and bleeding manifestations.Methods: Literature review.Results: On the basis of reports in the published literature, and our own clinical experience, we suggest that vasospasm is one of the principal drivers with hepatic ischemia, infarction, and hemorrhage as secondary events. It is known that vasoactive substances are released by the failing placenta. We suggest these cause severe vasospasm, most likely affecting the small post-sinusoidal hepatic venules. This leads to patchy or confluent hepatic ischemia and/or necrosis with a resultant increase in circulating liver enzymes. Reperfusion is associated with a fall in platelet count and microvascular hemorrhage if the microvasculature is infarcted. Blood tracks to the subcapsular space causing hematoma formation. If the hematoma ruptures the patient presents with severe abdominal pain, intra-abdominal hemorrhage, and shock.Conclusions: We suggest that hepatic and other complications associated with HELLP syndrome including placental abruption, acute renal failure, and posterior reversible encephalopathy syndrome (PRES) may also be due to regional vasospasm.
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Affiliation(s)
- P A McCormick
- Liver Unit, St Vincent's University Hospital, Dublin, Ireland
| | - M Higgins
- University College Dublin Perinatal Research Centre, National Maternity Hospital, Dublin, Ireland
| | - C A McCormick
- Department of Obstetrics and Gynaecology, The Royal Women's Hospital, Melbourne, Australia
| | - N Nolan
- Histopathology Department, St Vincent's University Hospital, Dublin, Ireland
| | - J R Docherty
- Physiology Department, Royal College of Surgeons in Ireland, Dublin, Ireland
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Docherty JR, Alsufyani HA. Cardiovascular and temperature adverse actions of stimulants. Br J Pharmacol 2021; 178:2551-2568. [PMID: 33786822 DOI: 10.1111/bph.15465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/22/2021] [Accepted: 03/10/2021] [Indexed: 12/11/2022] Open
Abstract
The vast majority of illicit stimulants act at monoaminergic systems, causing both psychostimulant and adverse effects. Stimulants can interact as substrates or antagonists at the nerve terminal monoamine transporter that mediates the reuptake of monoamines across the nerve synaptic membrane and at the vesicular monoamine transporter (VMAT-2) that mediates storage of monoamines in vesicles. Stimulants can act directly at presynaptic or postsynaptic receptors for monoamines or have indirect monoamine-mimetic actions due to the release of monoamines. Cocaine and other stimulants can acutely increase the risk of sudden cardiac death. Stimulants, particularly MDMA, in hot conditions, such as that occurring at a "rave," have caused fatalities from the consequences of hyperthermia, often compounding cardiac adverse actions. This review examines the pharmacology of the cardiovascular and temperature adverse actions of stimulants.
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Affiliation(s)
- James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Hadeel A Alsufyani
- Department of Physiology, King Abdulaziz University, Jeddah, Saudi Arabia
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Alsufyani HA, Docherty JR. Involvement of G proteins and Rho kinase in α 1-adrenoceptor mediated contractions of the rat portal vein. Can J Physiol Pharmacol 2020; 99:654-659. [PMID: 33096009 DOI: 10.1139/cjpp-2020-0347] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Contractions of the rat portal vein in response to the α1-adrenoceptor agonist phenylephrine consist of phasic contractions at low concentrations, with tonic contractions superimposed at higher concentrations. The α1D-adrenoceptor antagonist BMY7378 (7.0, -log M) did not affect phasic or tonic contractions to phenylephrine. The relatively nonselective α1-adrenoceptor antagonist prazosin (7.5) shifted equally the potencies of phenylephrine at producing phasic and tonic contractions, with pKB values of 8.85 and 8.83 (-log M), respectively. The α1A-adrenoceptor antagonist RS100329 (8.5) produced a significantly greater shift in phenylephrine potency for phasic (pKB of 10.51) than tonic contractions (pKB of 9.78). Prazosin was less effective than RS100329 at reducing the effects of phenylephrine on frequency of phasic contractions. The Rho kinase inhibitor fasudil (5.0) did not affect phasic contractions to phenylephrine, but significantly reduced tonic contractions. It is concluded that there is no evidence for involvement of α1D-adrenoceptors in responses of the rat portal vein to phenylephrine, but phasic responses involve predominantly α1A-adrenoceptors. Tonic responses may involve predominantly α1B-adrenoceptors and are at least partly mediated by mechanisms involving Rho kinase sensitive to fasudil.
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Affiliation(s)
- Hadeel A Alsufyani
- Department of Physiology, King Abdulaziz University, Jeddah, Saudi Arabia
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin, Ireland
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11
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George CH, Alexander SPH, Cirino G, Docherty JR, Hoyer D, Insel PA, Izzo AA, Ji Y, Panettieri RA, Sobey CG, Stanford SC, Stefanska B, Stephens G, Teixeira M, Ahluwalia A. The BJP expects authors to share data. Br J Pharmacol 2020; 176:4595-4598. [PMID: 31950490 DOI: 10.1111/bph.14907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
| | | | | | | | - Daniel Hoyer
- The University of Melbourne, Parkville, Victoria, Australia.,Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia.,The Scripps Research Institute, La Jolla, CA, USA
| | | | | | - Yong Ji
- Nanjing Medical University, Nanjing, China
| | | | | | | | - Barbara Stefanska
- The University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Mauro Teixeira
- Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Amrita Ahluwalia
- William Harvey Research Institute, Queen Mary University of London, London, UK
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12
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Lilley E, Stanford SC, Kendall DE, Alexander SP, Cirino G, Docherty JR, George CH, Insel PA, Izzo AA, Ji Y, Panettieri RA, Sobey CG, Stefanska B, Stephens G, Teixeira M, Ahluwalia A. ARRIVE 2.0 and the British Journal of Pharmacology: Updated guidance for 2020. Br J Pharmacol 2020; 177:3611-3616. [PMID: 32662875 PMCID: PMC7393193 DOI: 10.1111/bph.15178] [Citation(s) in RCA: 571] [Impact Index Per Article: 142.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Elliott Lilley
- Royal Society for the Prevention of Cruelty to AnimalsUK
| | | | | | | | | | | | | | | | | | - Yong Ji
- Nanjing Medical UniversityNanjingChina
| | | | | | | | | | | | - Amrita Ahluwalia
- William Harvey Research InstituteQueen Mary University of LondonLondonUK
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Abstract
The ongoing pandemic has stimulated study of the Renin Angiotensin Aldosterone System (RAAS), and how it can be manipulated to treat COVID-19. Studies are examining whether drugs that act on the RAAS system might be useful to treat COVID-19. COVID-19 and the RAAS are closely linked both in infection and in possible post-infection inflammatory cascades. We detail the Physiology and Pharmacology of the RAAS including the effects of aldosterone and atrial natriuretic peptide. It is appropriate that the theoretical benefits of modulation of the RAAS should be considered based on available knowledge of the complexity of the system. In this short review we have tried to explain the actions of the angiotensin family of peptides and produce a relatively simple model and diagrammatic summary of the RAAS and the possible sites of intervention.
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Affiliation(s)
- Hadeel A Alsufyani
- Department of Physiology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123, St. Stephen's Green, Dublin 2, Ireland
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Kenny RG, Ude Z, Docherty JR, Marmion CJ. Vorinostat and Belinostat, hydroxamate-based anti-cancer agents, are nitric oxide donors. J Inorg Biochem 2020; 206:110981. [DOI: 10.1016/j.jinorgbio.2019.110981] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 12/10/2019] [Accepted: 12/24/2019] [Indexed: 01/26/2023]
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15
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Izzo AA, Teixeira M, Alexander SPH, Cirino G, Docherty JR, George CH, Insel PA, Ji Y, Kendall DA, Panattieri RA, Sobey CG, Stanford SC, Stefanska B, Stephens G, Ahluwalia A. A practical guide for transparent reporting of research on natural products in the British Journal of Pharmacology: Reproducibility of natural product research. Br J Pharmacol 2020; 177:2169-2178. [PMID: 32298474 DOI: 10.1111/bph.15054] [Citation(s) in RCA: 170] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
| | - Mauro Teixeira
- Federal University of Minas Gerais, Belo Horizonte, Brazil
| | | | | | | | | | - Paul A Insel
- University of San Diego, San Diego, California, USA
| | - Yong Ji
- Nanjing University, Nanjing, China
| | | | | | | | | | - Barbara Stefanska
- The University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Amrita Ahluwalia
- William Harvey Research Institute, Queen Mary University of London, London, UK
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16
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Docherty JR, Stanford SC, Panattieri RA, Alexander SPH, Cirino G, George CH, Hoyer D, Izzo AA, Ji Y, Lilley E, Sobey CG, Stanley P, Stefanska B, Stephens G, Teixeira M, Ahluwalia A. Sex: A change in our guidelines to authors to ensure that this is no longer an ignored experimental variable. Br J Pharmacol 2019; 176:4081-4086. [PMID: 31441038 DOI: 10.1111/bph.14761] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
| | | | | | | | | | | | - Daniel Hoyer
- The University of Melbourne, Australia.,Florey Institute of Neuroscience and Mental Health, Australia.,The Scripps Research Institute, La Jolla, USA
| | | | - Yong Ji
- Nanjing Medical University, Nanjing, China
| | - Elliot Lilley
- Research Animals Department, Science Group, RSPCA, West Sussex, UK
| | | | - Phil Stanley
- Preclinical Research Statistics, UCB Pharma, Slough, UK
| | | | | | - Mauro Teixeira
- Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Amrita Ahluwalia
- William Harvey Research Institute, Queen Mary University of London, London, UK
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17
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Curtis MJ, Alexander S, Cirino G, Docherty JR, George CH, Giembycz MA, Hoyer D, Insel PA, Izzo AA, Ji Y, MacEwan DJ, Sobey CG, Stanford SC, Teixeira MM, Wonnacott S, Ahluwalia A. Experimental design and analysis and their reporting II: updated and simplified guidance for authors and peer reviewers. Br J Pharmacol 2019. [PMID: 29520785 DOI: 10.1111/bph.14153] [Citation(s) in RCA: 1078] [Impact Index Per Article: 215.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
This article updates the guidance published in 2015 for authors submitting papers to British Journal of Pharmacology (Curtis et al., 2015) and is intended to provide the rubric for peer review. Thus, it is directed towards authors, reviewers and editors. Explanations for many of the requirements were outlined previously and are not restated here. The new guidelines are intended to replace those published previously. The guidelines have been simplified for ease of understanding by authors, to make it more straightforward for peer reviewers to check compliance and to facilitate the curation of the journal's efforts to improve standards.
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Affiliation(s)
| | | | | | | | | | | | - Daniel Hoyer
- The University of Melbourne, Melbourne, VIC, Australia.,The Scripps Research Institute, San Diego, CA, USA
| | | | | | - Yong Ji
- Nanjing Medical University, Nanjing, China
| | | | | | | | - Mauro M Teixeira
- Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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18
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Abstract
This review examines the functions of α1-adrenoceptor subtypes, particularly in terms of contraction of smooth muscle. There are 3 subtypes of α1-adrenoceptor, α1A- α1B- and α1D-adrenoceptors. Evidence is presented that the postulated α1L-adrenoceptor is simply the native α1A-adrenoceptor at which prazosin has low potency. In most isolated tissue studies, smooth muscle contractions to exogenous agonists are mediated particularly by α1A-, with a lesser role for α1D-adrenoceptors, but α1B-adrenoceptors are clearly involved in contractions of some tissues, for example, the spleen. However, nerve-evoked responses are the most crucial physiologically, so that these studies of exogenous agonists may overestimate the importance of α1A-adrenoceptors. The major α1-adrenoceptors involved in blood pressure control by sympathetic nerves are the α1D- and the α1A-adrenoceptors, mediating peripheral vasoconstrictor actions. As noradrenaline has high potency at α1D-adrenceptors, these receptors mediate the fastest response and seem to be targets for neurally released noradrenaline especially to low frequency stimulation, with α1A-adrenoceptors being more important at high frequencies of stimulation. This is true in rodent vas deferens and may be true in vasopressor nerves controlling peripheral resistance and tissue blood flow. The αlA-adrenoceptor may act mainly through Ca2+ entry through L-type channels, whereas the α1D-adrenoceptor may act mainly through T-type channels and exhaustable Ca2+ stores. α1-Adrenoceptors may also act through non-G-protein linked second messenger systems. In many tissues, multiple subtypes of α-adrenoceptor are present, and this may be regarded as the norm rather than exception, although one receptor subtype is usually predominant.
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Affiliation(s)
- James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland.
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Docherty JR. α1D–Adrenoceptor Mediated Components to Nerve‐Evoked Contractions in Mouse Vas Deferens. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.lb381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Alsufyani HA, Docherty JR. Methylhexaneamine causes tachycardia and pressor responses indirectly by releasing noradrenaline in the rat. Eur J Pharmacol 2019; 843:121-125. [DOI: 10.1016/j.ejphar.2018.10.047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 09/17/2018] [Accepted: 10/30/2018] [Indexed: 11/16/2022]
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Alexander SPH, Roberts RE, Broughton BRS, Sobey CG, George CH, Stanford SC, Cirino G, Docherty JR, Giembycz MA, Hoyer D, Insel PA, Izzo AA, Ji Y, MacEwan DJ, Mangum J, Wonnacott S, Ahluwalia A. Goals and practicalities of immunoblotting and immunohistochemistry: A guide for submission to the British Journal of Pharmacology. Br J Pharmacol 2018; 175:407-411. [PMID: 29350411 DOI: 10.1111/bph.14112] [Citation(s) in RCA: 518] [Impact Index Per Article: 86.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Yong Ji
- British Journal of Pharmacology, London, UK
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Docherty JR, Alsufyani HA. Direct and Indirect Effects of Ephedrine on the Cardiovascular System. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.697.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Alsufyani HA, Docherty JR. Direct and indirect effects of ephedrine on heart rate and blood pressure in vehicle-treated and sympathectomised male rats. Eur J Pharmacol 2018; 825:34-38. [DOI: 10.1016/j.ejphar.2018.02.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Revised: 02/12/2018] [Accepted: 02/14/2018] [Indexed: 11/25/2022]
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Abstract
Background Topical α-adrenergic agonist therapy has been developed to treat the persistent erythema of rosacea patients. Brimonidine and oxymetazoline are both topical α-adrenergic agonists. Objectives The objective of this in vitro safety pharmacology study was to compare the potential safety profiles of brimonidine and oxymetazoline. Methods Brimonidine and oxymetazoline underwent pharmacological profiling with a standard panel of 151 assays, including α-adrenergic receptors and 5-hydroxytryptamine (5-HT) receptors. A valvular interstitial cell (VIC) proliferation assay was performed with oxymetazoline hydrochloride. Results Brimonidine was highly selective for the α2 adrenergic receptors, specifically α2A, whereas oxymetazoline was found to be much less selective and was highly active against a wide range of targets. Negligible activity was observed with brimonidine at the 5-HT2B receptor, whereas oxymetazoline had significant 5-HT2B receptor agonist activity and caused proliferation of mitral VICs in vitro. Conclusion As the 5-HT2B receptor is potentially involved in drug-induced valvulopathy, the benefit/risk ratio should be carefully considered, especially in patients with cardiovascular disease or other comorbidities.
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Affiliation(s)
| | - Atul Pathak
- Clinique Pasteur Toulouse, INSERM 1048, Toulouse, France
| | | | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin, Ireland
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George CH, Stanford SC, Alexander S, Cirino G, Docherty JR, Giembycz MA, Hoyer D, Insel PA, Izzo AA, Ji Y, MacEwan DJ, Sobey CG, Wonnacott S, Ahluwalia A. Updating the guidelines for data transparency in the British Journal of Pharmacology - data sharing and the use of scatter plots instead of bar charts. Br J Pharmacol 2017; 174:2801-2804. [PMID: 28801996 PMCID: PMC5554317 DOI: 10.1111/bph.13925] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Yong Ji
- British Journal of PharmacologyLondonUK
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Alsufyani HA, Docherty JR. Gender differences in the effects of cathinone and the interaction with caffeine on temperature and locomotor activity in the rat. Eur J Pharmacol 2017; 809:203-208. [PMID: 28529142 DOI: 10.1016/j.ejphar.2017.05.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 05/01/2017] [Accepted: 05/12/2017] [Indexed: 01/25/2023]
Abstract
We have investigated gender differences in the effects of cathinone and the interaction with caffeine on temperature and movement activity in Wistar rats. Telemetry probes were implanted in rats under isoflurane anaesthesia, and 7 days later, temperature and activity were recorded in conscious unrestrained animals. Caffeine (10mg/lkg) or vehicle, and 30min later, cathinone (5mg/kg) or vehicle, were injected subcutaneously. Cathinone produced significant and marked increases in activity, and the response to cathinone was significantly greater in female animals. The combination of caffeine and cathinone causes a short lived potentiation followed by a prolonged inhibition of the activity response to cathinone. Cathinone alone had minor effects on temperature. However, the combination of caffeine and cathinone produced a significant acute rise in temperature only in male rats in the 90min after cathinone injection. Hence, cathinone caused greater increases in activity in female than in male rats. Secondly, caffeine produced an initial potentiation followed by a prolonged inhibition of the activity response to cathinone. Thirdly, cathinone in combination with caffeine significantly raised temperature acutely in male but not female rats. These differences highlight the need to carry out gender studies of the actions of stimulants.
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Affiliation(s)
- Hadeel A Alsufyani
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland; Department of Physiology, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland.
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Docherty JR, McCormick PA. A carboxymethylcellulose-heparin combination for the prevention of surgical adhesions. J Surg Res 2017; 213:228-233. [PMID: 28601319 DOI: 10.1016/j.jss.2017.02.066] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/15/2017] [Accepted: 02/24/2017] [Indexed: 11/25/2022]
Abstract
BACKGROUND Adhesions are a major clinical problem after abdominal surgery. Despite decades of research, therapies to prevent adhesion formation are suboptimal. MATERIALS AND METHODS We have investigated combinations of carboxymethylcellulose (CMC) and heparin at preventing surgical adhesions in two rat models of adhesion formation. The first was the well-established cecal abrasion model, and the second was a model developed in our laboratory, the avascular mesenteric knot model. This model consistently produced adhesions at the knot in 90% of experiments and causes little or no tissue injury. RESULTS Topical administration of CMC 4% gave optimal results in the avascular knot model, but was less effective in the cecal abrasion model. This concentration of CMC was combined with a range of heparin doses between 0.5 and 160 IU/mL in the cecal abrasion model. These heparin doses, apart from the lowest (0.5 IU/mL), were effective in preventing adhesion formation in combination with CMC, as was the commercially available topical product Lipactin. The optimal dose was 30 IU/mL, that abolished adhesions, but there was little difference at doses between 2 and 160 IU. Heparin was effective in doses as low as 2 IU/mL when in combination with CMC. Heparin 160 IU/mL, but not heparin 30 IU/mL or Lipactin, significantly increased the degree of bleeding post cecal abrasion surgery. CONCLUSIONS Topical application of tiny doses of heparin, in combination with CMC 4% gel, significantly reduces adhesion formation in experimental models. We suggest that this cheap and, as far as we know, safe intervention should be evaluated in human clinical trials.
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Affiliation(s)
- James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin 2, Ireland.
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Alsufyani HA, Docherty JR. Direct and indirect cardiovascular actions of cathinone and MDMA in the anaesthetized rat. Eur J Pharmacol 2015; 758:142-6. [DOI: 10.1016/j.ejphar.2015.03.079] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 03/25/2015] [Accepted: 03/31/2015] [Indexed: 10/23/2022]
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Killian LM, Docherty JR. Cardiovascular stimulant actions of bupropion in comparison to cocaine in the rat. Eur J Pharmacol 2014; 735:32-7. [PMID: 24755144 DOI: 10.1016/j.ejphar.2014.03.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 03/27/2014] [Accepted: 03/31/2014] [Indexed: 11/30/2022]
Abstract
Stimulants are banned in competition by the World Anti-Doping Agency, except for a small number of therapeutic agents subject to monitoring, including bupropion. We have examined the potency of bupropion in comparison with two agents banned in competition, adrafinil and modafinil, and with cocaine and desipramine as blockers of the noradrenaline re-uptake transporter in peripheral tissues of the rat. For studies in vivo, the pressor response to noradrenaline in the anaesthetized rat was studied. Cocaine, desipramine and bupropion at doses of 0.1, 0.3 and 1mg/kg, respectively, significantly increased the pressor response to noradrenaline. Overall, cocaine and desipramine were approximately 2-5 times more potent than bupropion in vivo in the rat. Adrafinil and modafinil (both 3mg/kg) did not significantly affect the pressor response. Bupropion was chosen for further study. In 1Hz paced rat right ventricular strips, bupropion (30μM) significantly increased the potency of noradrenaline at increasing the force of contraction. In rat vas deferens, bupropion and cocaine produced concentration-dependent increases in the contractile response to nerve stimulation, and cocaine was 11 times more potent than bupropion. Since bupropion is used clinically in doses of up to 300mg, it is likely that bupropion has actions at the noradrenaline transporter, and thus cardiovascular stimulant actions, in clinical doses. This may explain findings of increased exercise performance with bupropion.
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Affiliation(s)
- Lyndsey M Killian
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St. Stephen׳s Green, Dublin 2, Ireland
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St. Stephen׳s Green, Dublin 2, Ireland.
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Chin JL, Aiden McCormick P, Docherty JR. Effects of portal hypertension on contractility of rat spleen. Eur J Pharmacol 2013; 721:1-4. [PMID: 24140433 DOI: 10.1016/j.ejphar.2013.09.063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 09/11/2013] [Accepted: 09/22/2013] [Indexed: 11/19/2022]
Abstract
Portal hypertension induces changes in vascular responses to vasoconstrictors. However, the effects of portal hypertension on splenic contraction have not previously been investigated. In partial portal vein ligated (PVL) and sham-operated rats, we examined the splenic contractile responses to cumulative concentrations of noradrenaline and KCl. In PVL rats, the potency of noradrenaline in producing splenic contraction was significantly increased (pEC50 of 5.88 ± 0.08), as compared to sham (5.40 ± 0.06; p<0.001). In the presence of prazosin (10(-8)M), there was a significant rightward shift in the noradrenaline concentration response curve but the shift was greater for PVL, so that in the presence of prazosin there was no significant difference between PVL and sham animals in the potency of noradrenaline. Prazosin produced a significantly greater shift of noradrenaline potency in spleen from PVL (pKB of 8.88 ± 0.06) (n=6) than from sham animals (8.51 ± 0.08, n=6), demonstrating that the α1-adrenoceptor mediated component is greater in spleen from PVL. In the presence of prazosin (10(-8)M) the residual response is non-α1-adrenoceptor mediated, presumably α2-adrenoceptor mediated, and this response did not differ between sham and PVL. The maximum splenic contraction did not significantly differ between sham and PVL rats for either agonist. In conclusion, noradrenaline potency in contracting the rat spleen was significantly increased in tissues from PVL rats. The increased potency of prazosin suggests a greater predominance of α1-adrenoceptors in spleen of PVL rats, as prazosin has lower potency at α2-adrenoceptors.
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Affiliation(s)
- Jun Liong Chin
- Liver Unit, St. Vincent's University Hospital, University College Dublin, Elm Park, Dublin 4, Ireland; Department of Physiology, Royal College of Surgeons in Ireland, 123, St. Stephen's Green, Dublin 2, Ireland
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Docherty JR, Bexis S. Influence of ketanserin on the effects of methylenedioxymethamphetamine on body temperature in the mouse. Auton Autacoid Pharmacol 2013; 33:35-41. [PMID: 23906337 DOI: 10.1111/aap.12009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 04/18/2013] [Accepted: 05/13/2013] [Indexed: 06/02/2023]
Abstract
(1) We have investigated the ability of the 5HT2 -receptor antagonist ketanserin to affect the hyperthermia produced by methylenedioxymethamphetamine (MDMA) in conscious mice and examined whether α1 -adrenoceptor antagonist actions are involved. (2) Mice were implanted with intra-abdominal temperature probes under anaesthesia and allowed 2 weeks recovery. MDMA (20 mg kg(-1) ) was administered subcutaneously 30 min after vehicle or test antagonist and effects on body temperature monitored by telemetry. (3) Following vehicle, MDMA produced a slowly developing hyperthermia, reaching a maximum increase of 1.24 °C at 150 min postinjection. Ketanserin (0.5 mg kg(-1) ) revealed a significant and marked early hypothermia to MDMA, an effect that is mimicked by the α1 -adrenoceptor antagonist prazosin (0.1 mg kg(-1) ). (4) Functional studies revealed antagonist actions of ketanserin at α1 -adrenoceptors in rat aorta and rat vas deferens in vitro indicative of α1 -adrenoceptor antagonist actions at the concentration used in vivo. (5) In conclusion, ketanserin (0.5 mg kg(-1) ) modulates the hyperthermic actions of MDMA in mice. Although we cannot rule out additional actions at 5HT2 -receptors, the actions of ketanserin are consistent with α1 -adrenoceptor antagonism. There is no clear evidence from this study that 5HT2-receptors mediate the hyperthermic response to MDMA.
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Affiliation(s)
- J R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin, Ireland
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Docherty JR. Evidence that the α1L‐adrenoceptor is the native α1A‐adrenoceptor in rat vas deferens. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.1096.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Docherty JR. Contractions of rat vas deferens are mediated by α1A‐ and α1D‐adrenoceptors. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1049.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Docherty JR. Re‐examination of role of α2‐adrenergic receptors in pithed rat pressor responses. FASEB J 2011. [DOI: 10.1096/fasebj.25.1_supplement.1021.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Docherty JR, Green AR. The role of monoamines in the changes in body temperature induced by 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) and its derivatives. Br J Pharmacol 2010; 160:1029-44. [PMID: 20590597 DOI: 10.1111/j.1476-5381.2010.00722.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Hyperthermia is probably the most widely known acute adverse event that can follow ingestion of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) by recreational users. The effect of MDMA on body temperature is complex because the drug has actions on all three major monoamine neurotransmitters [5-hydroxytryptamine (5-HT), dopamine and noradrenaline], both by amine release and by direct receptor activation. Hyperthermia and hypothermia can be induced in laboratory animals by MDMA, depending on the ambient temperature, and involve both central thermoregulation and peripheral changes in blood flow and thermogenesis. Acute 5-HT release is not directly responsible for hyperthermia, but 5-HT receptors are involved in modulating the hyperthermic response. Impairing 5-HT function with a neurotoxic dose of MDMA or p-chlorophenylalanine alters the subsequent MDMA-induced hyperthermic response. MDMA also releases dopamine, and evidence suggests that this transmitter is involved in both the hyperthermic and hypothermic effects of MDMA in rats. The noradrenergic system is also involved in the hyperthermic response to MDMA. MDMA activates central alpha(2A)-adrenoceptors and peripheral alpha(1)-adrenoceptors to produce cutaneous vasoconstriction to restrict heat loss, and beta(3)-adrenoceptors in brown adipose tissue to increase heat generation. The hyperthermia occurring in recreational users of MDMA can be fatal, but data reviewed here indicate that it is unlikely that any single pharmaceutical agent will be effective in reversing the hyperthermia, so careful body cooling remains the principal clinical approach. Crucially, educating recreational users about the potential dangers of hyperthermia and the control of ambient temperature should remain key approaches to prevent this potentially fatal problem.
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Affiliation(s)
- J R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, Ireland.
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Docherty JR, Seto SW. Thalidomide produces vascular relaxations. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.575.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Sai Wang Seto
- PhysiologyRoyal College of Surgeons in IrelandDublinIreland
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Abstract
BACKGROUND AND PURPOSE In rat vas deferens, nerve mediated-contractions to a single electrical stimulus consist of an early purinergic and a later adrenergic component with differing sensitivities to L-type calcium channel blockers. We have investigated the effects of the T-type calcium channel blockers mibefradil and (1S, 2S)-2-[2-[[3-(1H-benzimidazol-2-yl)propyl]methylamino]ethyl]-6-fluoro-1,2,3,4-tetrahydro-1-(1-methylethyl)-2-naphthalenyl cyclopropanecarboxylic dihydrochloride (NNC 55-0396) against contractions in rat vas deferens. In addition, the actions of thalidomide were examined. EXPERIMENTAL APPROACH Prostatic and epididymal portions of rat vas deferens were stimulated with a single electrical stimulus every 5 min, and mouse whole vas deferens was stimulated with 40 pulses at 10 Hz every 5 min. KEY RESULTS Both mibefradil and NNC 55-0396 (100 microM) produced inhibition of contractions of epididymal portions (42 +/- 13%, n= 7, and 43 +/- 4%, n= 15, of control respectively). However, both agents produced small inhibitions of responses in prostatic portions, presumably by L-type calcium channel block. Thalidomide (100 microM) inhibited contractions in epididymal (55 +/- 4% of control, n= 17) but not in prostatic portions of rat vas deferens. Thalidomide (10-100 microM) also inhibited contractions in mouse vas deferens. CONCLUSIONS AND IMPLICATIONS The T-type calcium channel blockers mibefradil and NNC 55-0396 block particularly the adrenoceptor-mediated, nifedipine-resistant response to nerve stimulation in rat vas deferens, and this may suggest that this component involves T-type calcium channels. In addition, thalidomide has actions that resemble those of the T-type calcium channel blockers, in that it blocks nifedipine-resistant contractions in epididymal portions.
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Affiliation(s)
- Sai Wang Seto
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin, Ireland
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Abstract
In this review, subtypes of functional alpha1-adrenoceptor are discussed. These are cell membrane receptors, belonging to the seven-transmembrane-spanning G-protein-linked family of receptors, which respond to the physiological agonist noradrenaline. alpha1-Adrenoceptors can be divided into alpha1A-, alpha1B- and alpha1D-adrenoceptors, all of which mediate contractile responses involving Gq/11 and inositol phosphate turnover. A fourth alpha1-adrenoceptor, the alpha1L-, represents a functional phenotype of the alpha1A-adrenoceptor. alpha1-Adrenoceptor subtype knock-out mice have refined our knowledge of the functions of alpha-adrenoceptor subtypes, particuarly as subtype-selective agonists and antagonists are not available for all subtypes. alpha1-Adrenoceptors function as stimulatory receptors involved particularly in smooth muscle contraction, especially contraction of vascular smooth muscle, both in local vasoconstriction and in the control of blood pressure and temperature, and contraction of the prostate and bladder neck. Central actions are now being elucidated.
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Affiliation(s)
- James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123, St. Stephen's Green, Dublin 2, Ireland.
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Bexis S, Docherty JR. Role of alpha 1- and beta 3-adrenoceptors in the modulation by SR59230A of the effects of MDMA on body temperature in the mouse. Br J Pharmacol 2009; 158:259-66. [PMID: 19422394 DOI: 10.1111/j.1476-5381.2009.00186.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE We have investigated the ability of the beta(3)-adrenoceptor antagonist 1-(2-ethylphenoxy)-3-[[(1S)-1,2,3,4,-tetrahydro-1-naphthalenyl]amino]-(2S)-2-propanol hydrochloride (SR59230A) to affect the hyperthermia produced by methylenedioxymethamphetamine (MDMA) in conscious mice and whether alpha(1)-adrenoceptor antagonist actions are involved. EXPERIMENTAL APPROACH Mice were implanted with temperature probes under anaesthesia, and allowed 2 week recovery. MDMA (20 mg x kg(-1)) was administered subcutaneously 30 min after vehicle or test antagonist and effects on body temperature monitored by telemetry. KEY RESULTS Following vehicle, MDMA produced a slowly developing hyperthermia, reaching a maximum increase of 1.8 degrees C at 130 min post injection. A low concentration of SR59230A (0.5 mg x kg(-1)) produced a small but significant attenuation of the slowly developing hyperthermia to MDMA. A high concentration of SR59230A (5 mg x kg(-1)) revealed a significant and marked early hypothermic reaction to MDMA, an effect that was mimicked by the alpha(1)-adrenoceptor antagonist prazosin. Functional and ligand binding studies revealed actions of SR59230A at alpha(1)-adrenoceptors. CONCLUSIONS AND IMPLICATIONS 1-(2-ethylphenoxy)-3-[[(1S)-1,2,3,4,-tetrahydro-1-naphthalenyl]amino]-(2S)-2-propanol hydrochloride in high concentrations modulates the hyperthermic actions of MDMA in mice in two ways: by blocking an early alpha(1)-adrenoceptor-mediated component to reveal a hypothermia, and by a small attenuation of the later hyperthermic component which may possibly be beta(3)-adrenoceptor-mediated (this seen with the low concentration of SR59230A). Hence, the major actions of SR59230A in modulating the actions of MDMA on temperature involve alpha(1)-adrenoceptor antagonism.
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Affiliation(s)
- Sotiria Bexis
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin, Ireland
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Bexis S, Cleary L, McGrath JC, Tanoue A, Tsujimoto G, Docherty JR. Alpha(1D)-adrenoceptors mediate nerve and agonist-evoked contractions in mouse vas deferens: evidence obtained from knockout technology. ACTA ACUST UNITED AC 2008; 28:81-5. [PMID: 18598289 DOI: 10.1111/j.1474-8673.2008.00420.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
1 It has been demonstrated that nerve-evoked contractions of the rat vas deferens involve alpha(1D)-adrenoceptors. Definitive evidence for a similar alpha(1D)-adrenoceptor-mediated response in mouse vas deferens has been more difficult to obtain. In this study, we have used alpha(1D)-adrenoceptor knockout (alpha(1D)-KO) mice to aid in the pharmacological characterization. 2 Mouse whole vas deferens was stimulated with a single pulse every 5 min. Once a stable response had been obtained, vehicle or antagonist was administered cumulatively at 5-min intervals and a response to stimulation obtained 5 min later. Cumulative concentration-response curves were also obtained for noradrenaline. 3 In vas deferens from alpha(1D)-KO mice, the contractile response to low concentrations of noradrenaline and the contractile response to a single stimulus were significantly reduced as compared to wild type (WT). 4 The alpha(1D)-adrenoceptor selective antagonist, BMY 7378, produced a concentration-dependent inhibition of single pulse-evoked contractions of vas deferens from WT and alpha(1D)-KO mice. BMY 7378 was significantly less potent in inhibiting stimulation-evoked contractions in vas deferens from alpha(1D)-KO mice. 5 It is concluded that alpha(1D)-adrenoceptors mediate a component of nerve- and agonist-evoked contractions of the vas deferens of WT mice.
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Affiliation(s)
- S Bexis
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland
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Docherty JR, Bexis S. Effects of a Beta3‐Adrenergic Antagonist on the Hyperthermic Response to MDMA in mice. FASEB J 2008. [DOI: 10.1096/fasebj.22.2_supplement.625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Sotiria Bexis
- PhysiologyRoyal College of Surgeons in IrelandDublinIreland
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Al Zubair K, Bexis S, Docherty JR. Relaxations to beta-adrenoceptor subtype selective agonists in wild-type and NOS-3-KO mouse mesenteric arteries. Eur J Pharmacol 2008; 587:216-23. [PMID: 18455721 DOI: 10.1016/j.ejphar.2008.03.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2007] [Revised: 02/27/2008] [Accepted: 03/10/2008] [Indexed: 12/16/2022]
Abstract
We have investigated the role of nitric oxide (NO) in relaxations to beta-adrenoceptor agonists in mesenteric artery from wild-type (WT) and NO synthase-3 knockout (NOS-3-KO) mice. Isoprenaline, formoterol and BRL 37344 ((R(),R())-(+/-)-4-[2-[(2-(3-chlorophenyl)-2-hydroxyethyl)amino]propyl]phenoxyacetic acid) were chosen as non-selective and beta(2)- and beta(3)-adrenoceptor agonists, respectively. Atenolol, ICI 118,551 ((+/-)-1-[2,3-(dihydro-7-methyl-1H-inden-4-yl)oxy]-3-[(1-methylethyl)amino]-2-butanol hydrochloride) and SR59230A (1-(2-ethylphenoxy)-3-[[(1S)-1,2,3,4-tetrahydro-1-naphthalenyl]amino]-(2S)-2-propanol hydrochloride) were chosen as selective beta(1)-, beta(2)- and beta(3)-adrenoceptor antagonists, respectively. Experiments employing isoprenaline were carried out in the presence of prazosin (0.1 microM). Isoprenaline produced relaxations with a potency of 5.68+/-0.36 (-log M, n=6) in WT mice. Relaxations to isoprenaline were blocked by atenolol (10 microM) and were absent in vessels from NOS-3-KO animals. Formoterol produced relaxations with two components. ICI 118,551 (1 microM) abolished relaxations to low concentrations of formoterol (0.1-10 microM), but failed to affect relaxations to formoterol (100 microM). In NOS-3-KO mice only the highest concentration of formoterol (100 microM) produced relaxations: the relaxation was resistant to all of the beta-adrenoceptor antagonists employed. BRL 37344 (5.75+/-0.28, n=9) was approximately equipotent with isoprenaline but produced a smaller degree of relaxation, in WT mice. SR59230A (1 microM) abolished relaxations to BRL 37344 in WT mice. In NOS-3-KO mice, BRL 37344 produced concentration-dependent relaxations which were abolished by SR59230A. It is concluded that the predominant beta-adrenoceptor mediating relaxations in mouse mesenteric artery is beta(1), and relaxations involve NOS-3. In addition, beta(3)-adrenoceptors mediate smaller relaxations at least partly independent of NOS-3, and beta(2)-adrenoceptors may mediate smaller relaxations dependent on NOS-3.
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Affiliation(s)
- Khaled Al Zubair
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St. Stephens's Green, Dublin 2, Ireland
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Bexis S, Docherty JR. Effects of MDMA, MDA and MDEA on blood pressure, heart rate, locomotor activity and body temperature in the rat involve alpha-adrenoceptors. Br J Pharmacol 2007; 147:926-34. [PMID: 16491100 PMCID: PMC2189797 DOI: 10.1038/sj.bjp.0706688] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The effects of injection of 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA) and N-ethyl-3,4-methylenedioxyamphetamine (MDEA) (all 20 mg kg(-1)) on blood pressure, heart rate, core body temperature and locomotor activity in conscious rats were investigated using radiotelemetry. MDMA and MDA produced a prolonged increase in both systolic and diastolic pressures, with MDA causing the most marked rise. MDEA produced a transient but nonsignificant fall in diastolic pressure. The pressor response produced by MDA was accompanied by bradycardia. All three amphetamine derivatives caused an initial hypothermic response; however, MDA also produced a subsequent hyperthermia, and the speed of recovery from hypothermia was MDA>MDMA>MDEA. The alpha2A-adrenoceptor antagonist 2-((4,5-dihydro-1H-imidazol-2-yl)methyl)-2,3-dihydro-1-methyl-1H-isoindole (BRL 44408) (1 mg kg(-1)) prolonged the hypothermic response to MDMA. Only MDA induced locomotor activity when given alone, but in the presence of BRL 44408, MDMA produced increased locomotor activity. The order of potency for producing isometric contractions of rat aorta (alpha1D) and vas deferens (alpha1A) was MDA>MDMA>MDEA, with MDEA acting as an alpha1-adrenoceptor antagonist with a pK(B) of 4.79+/-0.12 (n = 4) in aorta. The order of potency for prejunctional inhibition of stimulation-evoked contractions in rat vas deferens (alpha2A-adrenoceptor mediated) was MDA>MDMA>MDEA. Blood pressure actions of the three amphetamine derivatives may be at least partly due to alpha1-adrenoceptor agonism or antagonism. The reversal of the hypothermic actions are at least partly due to alpha2A-adrenoceptor agonism since the hypothermic response was more prolonged with MDEA which exhibits low alpha2A-adrenoceptor potency, and effects of MDMA after alpha2A-adrenoceptor antagonism were similar to those of MDEA.
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Affiliation(s)
- Sotiria Bexis
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland
- Author for correspondence:
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Abstract
Knock-out (KO) mouse technology has given pharmacologists a powerful tool to study function in the absence of selective antagonists or inhibitors. Such KO technology can confirm predicted function, serendipitously reveal unrecognized function, or help define the mode of action of a drug. In this issue, Liles et al. demonstrate, employing mice unable to synthesize noradrenaline due to the KO of the dopamine-beta-hydroxylase gene, that the sympathomimetic actions of ephedrine are directly, rather than indirectly, mediated. This may end 50 years of debate about the actions of ephedrine.
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Affiliation(s)
- J R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland.
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Abstract
1 We have investigated the actions of the alpha(1D)-adrenoceptor selective antagonist BMY 7378 in comparison with yohimbine at alpha(1)- and alpha(2)-adrenoceptors. 2 In rat aorta (alpha(1D)-adrenoceptor), BMY 7378 (pA(2) of 8.67) was about 100 times more potent than yohimbine (pA(2) of 6.62) at antagonizing the contractile response to noradrenaline. 3 In human saphenous vein (alpha(2C)-adrenoceptor), BMY 7378 (pA(2) of 6.48) was approximately 10 times less potent than yohimbine (pA(2) of 7.56) at antagonizing the contractile response to noradrenaline. 4 In prostatic portions of rat vas deferens, BMY 7378 (10 mum) did not significantly affect the concentration-dependent inhibition of single pulse nerve stimulation-evoked contractions by xylazine (an action at prejunctional alpha(2D)-adrenoceptors). 5 In ligand-binding studies, BMY 7378 showed 10-fold selectivity for alpha(2C)-adrenoceptors (pK(i) of 6.54) over other alpha(2)-adrenoceptors. 6 It is concluded that BMY 7378, in addition to alpha(1D)-adrenoceptor selectivity in terms of alpha(1)-adrenoceptors, shows selectivity for alpha(2C)-adrenoceptors in terms of alpha(2)-adrenoceptors.
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Affiliation(s)
- L Cleary
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
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Abstract
3,4-Methylenedioxymetamphetamine (MDMA) produces complex effects on body temperature, including hypo- and hyperthermic components that vary with ambient temperature and strain of rat. We have previously reported that MDMA is an alpha(2)-adrenoceptor agonist, and alpha(2)-adrenoceptor agonists such as clonidine produce hypothermia. The purpose of this study was to investigate the effects of MDMA on core body temperature measured by radiotelemetry in conscious wild-type (WT) and alpha(2A)-knockout (alpha(2A)-KO) mice. Clonidine (0.1 mg kg(-1), subcutaneously (s.c.)) produced a hypothermic response in WT mice, but did not significantly affect temperature in alpha(2)-KO mice. MDMA (20 mg kg(-1), s.c.) produced a significant hyperthermia in WT mice beginning at approximately 100 min after injection, recovering by 300 min, but produced a biphasic response, hypothermia followed by hyperthermia, in alpha(2)-KO mice. In WT mice, following the alpha(2A)-adrenoceptor antagonist 2-((4,5-dihydro-1H-imidazol-2-yl)methyl)-2,3-dihydro-1-methyl-1H-isoindole (1 mg kg(-1), s.c.), MDMA (20 mg kg(-1)) produced an initial hypothermia. Hence, alpha(2)-adrenoceptor agonist actions of MDMA contribute to its effects on body temperature, but in a surprising way. Although selective alpha(2A)-adrenoceptor agonism produces hypothermia, the alpha(2A)-adrenoceptor actions of MDMA alter the body temperature response to MDMA from biphasic (hypothermia followed by hyperthermia) to monophasic hyperthemia.
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Affiliation(s)
- Sotiria Bexis
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2
- Author for correspondence:
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Al Zubair K, Razak A, Bexis S, Docherty JR. Relaxations to oestrogen receptor subtype selective agonists in rat and mouse arteries. Eur J Pharmacol 2005; 513:101-8. [PMID: 15878714 DOI: 10.1016/j.ejphar.2005.03.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Accepted: 03/02/2005] [Indexed: 11/27/2022]
Abstract
It has been recently reported that the oestrogen receptor alpha agonist PPT (4,4',4"-(4-propyl-[1H]-pyrazole-1,3,5-triyl) tris-phenol) is more potent than the oestrogen receptor beta agonist DPN (2,3-bis(4-hydroxyphenyl)-propionitrile) at producing relaxations in rat mesenteric artery. We have investigated the relaxant actions of PPT and DPN in rat and mouse aorta and mesenteric artery. In rat aortic rings contracted with KCl (40 mM), the oestrogen receptor beta agonist DPN produced significantly greater relaxations than the oestrogen receptor alpha agonist PPT. In wild-type (WT) mouse aorta, the same result was found, but in WT mouse mesenteric artery, as in rat mesenteric artery, DPN was significantly less potent than PPT in females but had similar potency to PPT in males. Relaxations to DPN also occurred in aorta from nitric oxide synthase-3-knockout (NOS-3-KO) mice, and in denuded aorta from both mouse and rat. Hence, in the mouse mesenteric artery, as in the rat mesenteric artery, PPT is at least as potent as DPN at producing relaxations; however, DPN was much more potent than PPT in the rat and mouse aorta. Effects of oestrogen receptor subtype selective agonists are tissue dependent. In addition, actions are largely endothelium-independent.
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Affiliation(s)
- Khalid Al Zubair
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin
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Cleary L, Slattery J, Bexis S, Docherty JR. Sympathectomy reveals alpha 1A- and alpha 1D-adrenoceptor components to contractions to noradrenaline in rat vas deferens. Br J Pharmacol 2004; 143:745-52. [PMID: 15451776 PMCID: PMC1575931 DOI: 10.1038/sj.bjp.0705987] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We have previously demonstrated that contractions of rat vas deferens to exogenous noradrenaline involve predominantly alpha(1A)-adrenoceptors, but that contractions to endogenous noradrenaline involve predominantly alpha(1D)-adrenoceptors. In this study, we have examined the effects of sympathectomy on the subtypes of alpha(1)-adrenoceptor in rat vas deferens in radioligand binding and functional studies. In vehicle-treated tissues, antagonist displacement of [(3)H]prazosin binding to alpha(1)-adrenoceptors was consistent with a single population of alpha(1)-adrenoceptors. Binding affinities for a range of alpha(1)-adrenoceptor antagonists were expressed as pK(i) values and correlated with known affinities for alpha(1)-adrenoceptor subtypes. The correlation was significant only with alpha(1A)-adrenoceptors. In tissues from rats sympathectomised with 6-hydroxy-dopamine (2 x 100 mg kg(-1) i.p.), binding affinity for the alpha(1D)-adrenoceptor antagonist BMY 7378 fitted best with a two-site model. In functional studies, the potency of noradrenaline at producing total (phasic plus tonic) but not tonic contractions was increased in tissues from sympathectomised rats. Results obtained from sympathectomised rats suggest that phasic contractions are mainly alpha(1D)-adrenoceptor mediated, whereas tonic contractions are mainly alpha(1A)-adrenoceptor mediated, based on the effects of BMY 7378 and the alpha(1A)-adrenoceptor antagonist RS 100329. It is concluded that the predominant alpha(1)-adrenoceptor in vehicle-treated rat vas deferens is the alpha(1A)-adrenoceptor, both in terms of ligand binding and contractions to exogenous agonists. The alpha(1D)-adrenoceptor is only detectable by ligand binding following chemical sympathectomy, but is involved in noradrenaline-evoked contractions, particularly phasic contractions, of rat vas deferens.
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Affiliation(s)
- Linda Cleary
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland
| | - James Slattery
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland
| | - Sotiria Bexis
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland
| | - James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland
- Author for correspondence:
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Bexis S, Vandeputte C, McCormick PA, Docherty JR. Deletion of inducible nitric oxide synthase decreases mesenteric vascular responsiveness in portal hypertensive mice. Eur J Pharmacol 2004; 499:325-33. [PMID: 15381055 DOI: 10.1016/j.ejphar.2004.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2004] [Revised: 07/29/2004] [Accepted: 08/03/2004] [Indexed: 02/09/2023]
Abstract
The effects of pre-hepatic portal hypertension were examined on the responsiveness of aorta and mesenteric artery from wild-type, inducible nitric oxide synthase knockout (iNOS-KO) and endothelial nitric oxide synthase knockout (eNOS-KO) mice. Mice were sham-operated or made portal hypertensive by creating a calibrated portal vein stenosis. Acetylcholine produced marked relaxations in phenylephrine (10 microM) contracted aorta and mesenteric artery from wild-type and iNOS-KO, both sham and portal hypertensive, but relaxations were abolished in vessels from eNOS-KO mice. There were no significant differences between sham and portal hypertensive animals within groups in the effects of acetylcholine. The potency of KCl was significantly increased in aorta and mesenteric artery from eNOS-KO mice. The maximum contraction to the alpha(1)-adrenoceptor agonist phenylephrine was significantly increased in aorta from eNOS-KO, as compared with wild-type mice. There were no significant differences between sham and portal hypertensive animals within each group in contractions of aorta to KCl or phenylephrine. However, in mesenteric artery, although portal hypertension did not change responsiveness in wild-type or eNOS-KO as compared to sham animals, the potency of phenylephrine was significantly reduced in portal hypertensive iNOS-KO mice as compared to shams. Hence, portal hypertension as compared to sham operation did not affect responses to vasoconstrictors in mouse aorta, but in mouse mesenteric artery portal hypertension affected vascular responses in iNOS-KO mice, suggesting that iNOS is involved in the mesenteric vascular response to portal vein ligation.
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Affiliation(s)
- Sotiria Bexis
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin 2, Ireland
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