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Hernandez-Cascales J. Resveratrol enhances the inotropic effect but inhibits the proarrhythmic effect of sympathomimetic agents in rat myocardium. PeerJ 2017; 5:e3113. [PMID: 28382232 PMCID: PMC5376116 DOI: 10.7717/peerj.3113] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 02/21/2017] [Indexed: 01/01/2023] Open
Abstract
Background Resveratrol is a cardioprotective agent with known antiarrhythmic effects that has recently been shown to inhibit phosphodiesterase (PDE) enzyme activity. Thus, it is possible that resveratrol increases the inotropic effect of sympathomimetic agents, as PDE inhibitors do but, unlike other PDE inhibitors, its effect may not be accompanied by proarrhythmia due to its antiarrhythmic action. This work is aimed to test this hypothesis. Methods This is an “in vitro” concentration-response relationship study. The effects of noradrenaline, tyramine and isoproterenol, alone or in combination with either resveratrol or with the typical PDE inhibitor 3-isobutylmethylxantine (IBMX), were studied in electrically driven strips of right ventricle or in the spontaneously beating free wall of the right ventricle of rat heart in order to investigate inotropic or proarrhythmic effects respectively. Also, the effects of resveratrol or IBMX on the sinoatrial node rate were examined in the isolated right atria of rat heart. Results Resveratrol (10 µM and 100 µM) produces a leftward shift in the concentration-response curves for the contractile effects of noradrenaline, tyramine or isoproterenol and reduces the –log EC50 values of these three agents. IBMX produces similar effects. The spontaneous ventricular beating rate was increased by all three compounds, an effect that was further enhanced by the addition of IBMX. In contrast, resveratrol (100 µM) abolished the effects of these sympathomimetic agents on the ventricular rate. Resveratrol (1–100 µM) had no effect on the sinoatrial node rate, while IBMX produce a concentration dependent sinoatrial tachycardia. Discussion Taken together, the finding, indicate that resveratrol, like the PDE inhibitor IBMX enhances the contractile effects of sympathomimetic agents but, in contrast to IBMX, it does not enhance their proarrhythmic effect or produce sinoatrial tachycardia. This is most probably consequence of the antiarrhythmic effect of resveratrol which protect against the proarrhythmic effects resulting from PDE inhibition.
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Affiliation(s)
- Jesús Hernandez-Cascales
- Department of Pharmacology, Faculty of Medicine, University of Murcia , Espinardo-Murcia , Spain
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Gonzalez-Muñoz C, Fuente T, Medin-Aguerre S, Hernández-Cascales J. The increase in rat ventricular automaticity induced by salbutamol is mediated through β(1)- but not β(2)-adrenoceptors: role of phosphodiesterases. Life Sci 2011; 88:1095-101. [PMID: 21565204 DOI: 10.1016/j.lfs.2011.04.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Revised: 03/14/2011] [Accepted: 03/31/2011] [Indexed: 10/18/2022]
Abstract
AIMS While β(2)-adrenoceptor (AR) agonists are useful bronchodilators, they also produce cardiac arrhythmias. These agents are not fully selective and also activate β(1)-AR, but the involvement of β(1)-AR and β(2)-AR in the observed pro-arrhythmic effect has not been established. We studied the effect of β(1)-AR and β(2)-AR activation on ventricular automaticity and the role of phosphodiesterases (PDE) in regulating this effect. MAIN METHODS Experiments were performed in the spontaneously beating isolated right ventricle of the rat heart. We also measured cAMP production in this tissue. KEY FINDINGS The β(2)-AR agonist salbutamol (1-100 μM) produced a concentration-dependent increase in ventricular automaticity that was not affected by 50nM of the β(2)-AR antagonist ICI 118551. This effect was enhanced by the non-selective PDE inhibitor theophylline (100 μM) and by the selective PDE4 inhibitors rolipram (1 μM) and Ro 201724 (2 μM), but not modified by the selective PDE3 inhibitors cilostamide (0.3 μM) or milrinone (0.2 μM). The effects of salbutamol alone and in the presence of either theophylline or rolipram were virtually abolished by 0.1 μM β(1)-AR antagonist CGP 20712A. Salbutamol (10 μM) increased the cAMP concentration, and this effect was abolished by CGP 20712A (0.1 μM) but enhanced by theophylline (100 μM) or rolipram (1 μM). Cilostamide (0.3 μM) failed to modify the effect of salbutamol on cAMP concentration. SIGNIFICANCE These results indicate that the increase of ventricular automaticity elicited by salbutamol was exclusively mediated through β(1)-AR and enhanced by non-selective PDE inhibition with theophylline or selective PDE4 inhibition. However, PDE3 did not appear to regulate this effect.
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Affiliation(s)
- Carmen Gonzalez-Muñoz
- Department of Pharmacology, Medical School and Unit of Radiopharmacy, University Hospital Virgen de la Arrixaca, Murcia, Spain
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GONZALEZ-MUÑOZ C, HERNÁNDEZ J. Phosphodiesterases Inhibition Enhances the Effect of Glucagon on Cardiac Automaticity in the Isolated Right Ventricle of the Rat. Physiol Res 2011; 60:189-92. [DOI: 10.33549/physiolres.932023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We evaluated the effect of glucagon on cardiac automaticity as well as the possible role of cyclic nucleotide phosphodiesterases (PDE) in regulating this effect. Concentration response curves for glucagon in the absence and in the presence of the non-selective PDE inhibitor IBMX were performed in the isolated right ventricle of the rat. We found that glucagon produces only a minor increase of ventricular automaticity (11.0±4.1, n=5) when compared to the full agonist of β-adrenoceptor isoproterenol (182.2±25.3, n=7). However, IBMX enhances the maximal efficacy of glucagon on cardiac automaticity (11.0±4.1, in the absence and 45.3±3.2 in the presence of IBMX, n=5, P<0.05). These results indicate that PDE blunts proarrhythmic effects of glucagon in rat myocardium.
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Affiliation(s)
| | - J. HERNÁNDEZ
- Department of Pharmacology, Medical School, University of Murcia, Murcia, Spain
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Abstract
ATP, besides an intracellular energy source, is an agonist when applied to a variety of different cells including cardiomyocytes. Sources of ATP in the extracellular milieu are multiple. Extracellular ATP is rapidly degraded by ectonucleotidases. Today ionotropic P2X(1--7) receptors and metabotropic P2Y(1,2,4,6,11) receptors have been cloned and their mRNA found in cardiomyocytes. On a single cardiomyocyte, micromolar ATP induces nonspecific cationic and Cl(-) currents that depolarize the cells. ATP both increases directly via a G(s) protein and decreases Ca(2+) current. ATP activates the inward-rectifying currents (ACh- and ATP-activated K(+) currents) and outward K(+) currents. P2-purinergic stimulation increases cAMP by activating adenylyl cyclase isoform V. It also involves tyrosine kinases to activate phospholipase C-gamma to produce inositol 1,4,5-trisphosphate and Cl(-)/HCO(3)(-) exchange to induce a large transient acidosis. No clear correlation is presently possible between an effect and the activation of a given P2-receptor subtype in cardiomyocytes. ATP itself is generally a positive inotropic agent. Upon rapid application to cells, ATP induces various forms of arrhythmia. At the tissue level, arrhythmia could be due to slowing of electrical spread after both Na(+) current decrease and cell-to-cell uncoupling as well as cell depolarization and Ca(2+) current increase. In as much as the information is available, this review also reports analog effects of UTP and diadenosine polyphosphates.
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Affiliation(s)
- G Vassort
- Institut National de la Santé et de la Recherche Médicale U. 390, Centre Hospitalier Universitaire Arnaud de Villeneuve, Montpellier, France.
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He ZX, Cwajg E, Hwang W, Hartley CJ, Funk E, Michael LH, Verani MS. Myocardial blood flow and myocardial uptake of (201)Tl and (99m)Tc-sestamibi during coronary vasodilation induced by CGS-21680, a selective adenosine A(2A) receptor agonist. Circulation 2000; 102:438-44. [PMID: 10908217 DOI: 10.1161/01.cir.102.4.438] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND We investigated the hemodynamic and coronary vasodilatory effects of CGS-21680, a potent selective adenosine A(2A) agonist, as well as its potential use as a new stress modality in combination with perfusion scintigraphy. METHODS AND RESULTS A stenosis of the left anterior descending coronary artery (LAD) was produced in dogs to reduce the reactive hyperemic response to <20%. Adenosine and CGS-21680 were then separately infused to maximize left circumflex coronary artery (LCx) flow velocity. (201)Tl (0.5 mCi) and (99m)Tc-sestamibi (5 mCi) were injected at the maximal dose of CGS-21680. Heart rate decreased with adenosine but increased during CGS-21680 infusion (P<0.005). The decrease in systolic blood pressure was more prominent with adenosine than with CGS-21680 (P<0.005). In the control LCx zone, maximal myocardial blood flow (MBF) (measured by radioactive microspheres) increased 3.1-fold during adenosine infusion (P<0.005) and 3.8-fold during CGS-21680 infusion (P<0.005). In the stenotic LAD zone, MBF did not change significantly. During adenosine and CGS-21680 infusion, stenosis/control zone MBF ratios were comparable (0.32+/-0.11 versus 0.27+/-0.10, P=NS), and transmural (201)Tl and (99m)Tc-sestamibi count-activity ratios (0.48+/-0.11 and 0.51+/-0.09, respectively) were also comparable (P=NS). Myocardial scintigraphy uncovered perfusion defects in all dogs. CONCLUSIONS CGS-21680 elicits coronary vasodilation comparable to that of adenosine and produces profound heterogeneity of MBF and of (201)Tl and (99m)Tc-sestamibi myocardial uptake, rendering it a promising agent for pharmacological myocardial perfusion imaging.
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Affiliation(s)
- Z X He
- Section of Cardiology, Baylor College of Medicine/Methodist Hospital, Houston, Tex, USA
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Nekooeian AA, Tabrizchi R. Haemodynamic effects of a selective adenosine A2A receptor agonist, CGS 21680, in chronic heart failure in anaesthetized rats. Br J Pharmacol 1998; 125:651-8. [PMID: 9831898 PMCID: PMC1571031 DOI: 10.1038/sj.bjp.0702105] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Recently we demonstrated that the administration of an A2A adenosine receptor agonist, CGS 21680, to anaesthetized rats with acute heart failure (1 h post-coronary artery ligation) resulted in an increase in cardiac output. In the present investigation, the effects of CGS 21680 on cardiac output, vascular resistance, heart rate, blood pressure and mean circulatory filling pressure (Pmcf) were investigated in anaesthetized rats with chronic heart failure (8 weeks post-coronary artery ligation). 2. Experiments were conducted in five groups (n = 6) of animals: sham-operated vehicle-treated (0.9% NaCl; 0.037 mL kg(-1) min(-1)) animals in which the occluder was placed but not pulled to ligate the coronary artery; coronary artery-ligated vehicle-treated animals; and coronary artery-ligated CGS 21680-treated (0.1. 0.3 or 1.0 microg kg(-1) min(-1)) animals. 3. Baseline blood pressure, cardiac output and rate of rise in left ventricular pressure (+dP/dt) were significantly reduced in animals with coronary artery ligation when compared to sham-operated animals. Coronary artery ligation resulted in a significant increase in left ventricular end-diastolic pressure, Pmcf and venous resistance when compared to sham-operated animals. 4. Administration of CGS 21680 at 0.3 and 1.0 microg kg(-1) min(-1) significantly (n = 6; P<0.05) increased cardiac output by 19+/-4% and 39+/-5%, and heart rate by 14+/-2% and 15+/-1%, respectively, when compared to vehicle treatment in coronary artery-ligated animals. Administration of CGS 21680 also significantly reduced blood pressure and arterial resistance when compared to coronary artery-ligated vehicle-treated animals. Infusion of CGS 21680 also significantly reduced venous resistance when compared to vehicle-treated coronary artery-ligated animals. 5. The results show that heart failure is characterized by reduced cardiac output, and increased left ventricular end-diastolic pressure, venous resistance and Pmcf. Acute treatment with CGS 21680 in animals with chronic heart failure decreased left ventricular end-diastolic pressure and increased cardiac output. This increase in cardiac output was the result of reduced arterial and venous resistances and increased heart rate.
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Affiliation(s)
- A A Nekooeian
- Department of Pharmacology and Therapeutics, Faculty of Medicine, The University of British Columbia, Vancouver, Canada
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Tang XL, Wang HX, Cho CH, Wong TM. Reduced responsiveness of [Ca2+]i to adenosine A1- and A2-receptor stimulation in the isoproterenol-stimulated ventricular myocytes of spontaneously hypertensive rats. J Cardiovasc Pharmacol 1998; 31:493-8. [PMID: 9554795 DOI: 10.1097/00005344-199804000-00004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
To determine the modulatory action of adenosine-receptor stimulation on [Ca2+]i responses to beta-adrenoceptor stimulation in the heart of the spontaneously hypertensive rat (SHR), the electrically induced [Ca2+]i transient in response to isoproterenol (ISO) in single ventricular myocytes pretreated with adenosine agonists in SHRs and its normotensive control Wistar-Kyoto (WKY) rats was measured with a spectrofluorometric method by using fura-2/AM as the calcium indicator. In both types of rat, ISO at 0.001-1 microM augmented the electrically induced [Ca2+]i transient, and the effect was blocked by a beta-adrenoceptor blocker, propranolol. In SHRs that did not exhibit cardiac hypertrophy, the resting level of [Ca2+]i and the amplitude of the electrically induced [Ca2+]i transient were the same as those in WKY rats, whereas the augmentation of the electrically induced [Ca2+]i transient in response to ISO was significantly lower than that in WKY rats. In WKY rats, the effects of ISO on the electrically induced [Ca2+]i transient were inhibited by the adenosine A1-receptor agonist, R(-)-N6-(2-phenylisopropyl)adenosine (R-PIA) at 0.01-10 microM. In contrast, the effects of ISO were further enhanced by the adenosine A2-receptor agonist, N6-[2-(3,5-dimethoxyphenyl)-2-(2-methylphenyl)-ethyl)]adenosine (DPMA) at 1-10 microM. In SHRs, the inhibitory effect of R-PIA was significantly reduced, whereas the excitatory effect of DPMA was absent. The effects of both adenosine-receptor agonists in both types of rat were abolished by the respective adenosine-receptor antagonists, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) and 3,7-dimethyl-1-propargylxanthine (DMPX). The results indicate that the modulatory actions of adenosine-receptor stimulation on [Ca2+]i response to beta-adrenoceptor stimulation in the hearts of SHRs are reduced, which is independent of cardiac hypertrophy.
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Affiliation(s)
- X L Tang
- Department of Physiology, Institute of Cardiovascular Science and Medicine, The University of Hong Kong, Hong Kong
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Nekooeian AA, Tabrizchi R. Effects of adenosine A2A receptor agonist, CGS 21680, on blood pressure, cardiac index and arterial conductance in anaesthetized rats. Eur J Pharmacol 1996; 307:163-9. [PMID: 8832218 DOI: 10.1016/0014-2999(96)00250-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine (CGS 21680) on blood pressure, total peripheral resistance, cardiac index, heart rate and arterial conductance in different vascular beds in the presence and absence of hexamethonium (ganglionic blocker) and phenylephrine (alpha 1-adrenoceptor agonist) were investigated in pentobarbitone-anaesthetized rats using a radioactive microsphere technique. CGS 21680 (0.1, 0.3 and 1.0 microgram/kg/min) significantly decreased blood pressure and total peripheral resistance, and increased heart rate and cardiac index. In addition, after infusion with CGS 21680 (0.1, 0.3 and 1.0 microgram/kg/min) arterial conductance in coronary bed significantly increased. However, while CGS 21680 (0.3 and 1.0 microgram/kg/min) significantly increased conductance in skeletal muscle, it significantly decreased splenic arterial conductance. Moreover, CGS 21680 (1.0 microgram/kg/min) significantly increased conductance in cerebral arterial bed. Infusion with hexamethonium (200 micrograms/kg/min) resulted in significant reduction in blood pressure, heart rate and cardiac index whereas stroke volume and total peripheral resistance remained unchanged. In animals that were pretreated with hexamethonium (200 micrograms/kg/min), further administration of CGS 21680 (0.3 microgram/kg/min), compared to CGS 21680 alone, significantly reduced blood pressure, heart rate and cardiac index but did not affect total peripheral resistance or conductance in any vascular bed. Administration of phenylephrine (7 micrograms/kg/min) resulted in a significant increase in blood pressure and total peripheral resistance, and a significant reduction in cardiac index and heart rate. In animals infused with phenylephrine and CGS 21680 combined, in comparison to those animals that received CGS 21680 alone, no significant differences in blood pressure, heart rate, total peripheral resistance, cardiac index or conductance in any vascular beds were found. Our present findings suggest that CGS 21680 decreased blood pressure by decreasing total peripheral resistance, and increased cardiac index possibly through a reflex-mediated increase in heart rate. Moreover the coronary arterial bed is the most sensitive and cerebral arterial bed is the least sensitive to the effects of CGS 21680. In addition, the autonomic nervous system did not appear to play a major role in the actions of CGS 21680 on arterial conductance, and there was no difference in the action of this compound in the states of normal and raised vascular tone.
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Affiliation(s)
- A A Nekooeian
- Department of Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, Canada
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Abstract
Due to its negative chronotropic and inotropic effects, adenosine has to date been considered as a cardiodepressant agent. However, adenosine increases ventricular automaticity. This review by Jesus Hernández and Alexandre Ribeiro discusses the experimental and clinical evidence for the excitatory effects of adenosine on ventricular automaticity, as well as the possible mechanisms involved in the ventricular dysrhythmias that occur during the diagnostic and therapeutic use of adenosine.
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Affiliation(s)
- J Hernández
- Department of Pharmacology, Medical School, Murcia, Spain
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Abstract
Adenosine is considered a cardiodepressant agent due to its negative chronotropic and inotropic effects. However, the effect of adenosine on ventricular automaticity is less well established since both an increase and a decrease in ventricular automaticity have been reported. The experimental and clinical evidence dealing with the effects of adenosine on ventricular automaticity as well as the possible mechanisms involved, is presented in this review.
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Affiliation(s)
- J Hernández
- Department of Pharmacology, Medical School, Murcia, Spain
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Martinez E, Peñafiel R, Collado MC, Hernández J. Diazepam potentiates the positive inotropic effect of isoprenaline in rat ventricle strips: role of cyclic AMP. Eur J Pharmacol 1995; 282:169-75. [PMID: 7498272 DOI: 10.1016/0014-2999(95)00325-f] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The responses of the electrically driven right ventricle strip of the rat heart to isoprenaline and other cyclic AMP-related inotropic agents were recorded in the absence and in the presence of diazepam. Isoprenaline, in concentrations ranging from 10 nM to 1 microM, significantly increased, in a concentration-dependent manner, the contractile force in this preparation. Diazepam (10 microM) produced a leftward shift in the isoprenaline concentration-response curve and significantly reduced its EC50. Higher concentrations of diazepam (100 microM) produced no further shift, but reduced the maximum of the concentration-response curve of isoprenaline. Forskolin (0.5-10 microM), which directly stimulates adenyl cyclase, also produced a concentration-dependent increase in cardiac contractility. Diazepam (10 microM) displaced to the left the concentration-response curve for forskolin and reduced its EC50. The cyclic AMP analogous dibutyryl cyclic AMP (0.1-1 mM) produced concentration-dependent positive inotropic effects which were not significantly modified in the presence of diazepam (10 microM). Diazepam (10 microM) significantly enhanced the cyclic AMP production induced by isoprenaline (0.1 microM) and forskolin (10 microM) by about 136% and 35% respectively. These results indicate that diazepam potentiates the positive inotropic effect induced by beta-adrenoceptor agonists, probably by increasing cyclic AMP production induced by these agents.
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Affiliation(s)
- E Martinez
- Department of Pharmacology, Medical School, Murcia, Spain
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Hernández J, Pinto F, Ribeiro JA. Involvement of alpha-adrenoceptors in the excitatory effect of the A2 adenosine receptors agonist 5'-N-ethylcarboxamidoadenosine (NECA) on cardiac automaticity in the isolated right ventricle of the rat. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1994; 350:632-7. [PMID: 7708120 DOI: 10.1007/bf00169368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effects of the non-selective A2 adenosine receptor agonist 5'-N-ethyl-carboxamidoadenosine (NECA) were studied on ventricular automaticity induced by a local injury in the isolated right ventricle of the rat. In concentrations ranging from 0.1 to 100 nM, NECA significantly increased ventricular automaticity. This effect was not apparent when the nonselective alpha-adrenoceptor blocker phenoxybenzamine was present at a concentration of 10 microM, which antagonizes both alpha 1- and alpha 2-adrenoceptors, as well as when rats were pretreated with reserpine. In non-reserpinized rats, the excitatory effect of NECA was also abolished in the presence of the selective alpha 1-adrenoceptor antagonist prazosin, but not in the presence of the alpha 2-adrenoceptor antagonist idazoxan. In reserpinized rats, the excitatory effect of NECA was restored in the presence of the non specific alpha-adrenoceptor agonist phenylephrine as well as in the presence of the selective alpha 1-adrenoceptor agonist amidephrine but not in the presence of the selective alpha 2-adrenoceptor agonist clonidine. These results suggest that the excitatory effect of NECA on ectopic ventricular automaticity is dependent on endogenous catecholamines and that alpha-adrenoceptors of type 1 are, in some way, involved in this effect.
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Affiliation(s)
- J Hernández
- Department of Pharmacology, Medical School, Murcia, Spain
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