MECHANISMS UNDERLYING THE CARDIOVASCULAR ACTION OF A NEW DIHYDROPYRIDINE VASODILATOR, YC‐93
- 28 June 1980
- journal article
- Published by Wiley in Clinical and Experimental Pharmacology and Physiology
- Vol. 7 (3), 249-262
- https://doi.org/10.1111/j.1440-1681.1980.tb00069.x
Abstract
1. The mechanisms underlying the cardiovascular action of YC-93, a new dihydropyridine vasodilator with cyclic AMP phosphodiesterase inhibitory activity, was investigated by comparing its effects with those of papaverine in various isolated, blood-perfused heart preparations of the dog. 2. In all preparations YC-93 injected into the nutrient arteries produced a dose-dependent increase in blood flow, and in this respect YC-93 was about twenty times more potent than papaverine on a weight basis. 3. In sinoatrial node preparations YC-93 injected into the sinus node artery decreased sinus rate in a dose-dependent manner, and in large doses produced atrial standstill. 4. In atrioventricular (a.v.) node preparations YC-93 injected into the a.v. node artery increased a.v. conduction time in a dose-dependent manner, and in large doses produced a second or third degree block of a.v. conduction. However YC-93 injected into the anterior septal artery scarcely affected a.v. conduction. 5. In spontaneously contracting papillary muscle preparations YC-93 injected into the anterior septal artery failed to affect ventricular automaticity in doses which markedly decreased developed tension of papillary muscles. 6. In papillary muscle preparations driven at a fixed rate YC-93 injected into the anterior septal artery produced a dose-dependent decrease in developed tension of papillary muscles. 7. Unlike YC-93, papaverine decreased a.v. conduction time in a.v. node preparations and increased developed tension of papillary muscle preparations. 8. The cardiac effects of YC-93 elucidated in the present experiments are characteristic of calcium-antagonistic vasodilators. The action of YC-93 as an inhibitor of cyclic AMP phosphodiesterase does not appear to play a role in its cardiac action.Keywords
This publication has 19 references indexed in Scilit:
- Effects of papaverine and its interaction with isoprenaline and carbachol on the contractile force and cyclic nucleotide levels of the canine ventricular myocardiumNaunyn-Schmiedebergs Archiv für experimentelle Pathologie und Pharmakologie, 1979
- Calcium, Calcium‐antagonistic Drugs and the HeartActa Pharmacologica et Toxicologica, 1978
- Effects of calcium-antagonistic coronary vasodilators, nifedipine and verapamil, on ventricular automaticity of the dogNaunyn-Schmiedebergs Archiv für experimentelle Pathologie und Pharmakologie, 1978
- Specific Pharmacology of Calcium in Myocardium, Cardiac Pacemakers, and Vascular Smooth MuscleAnnual Review of Pharmacology and Toxicology, 1977
- Effects on atrio-ventricular conduction of calcium-antagonistic coronary vasodilators, local anaesthetics and quinidine injected into the posterior and the anterior septal artery of the atrio-ventricular node preparation of the dogNaunyn-Schmiedebergs Archiv für experimentelle Pathologie und Pharmakologie, 1976
- Pharmacologic analysis of papaverine-induced positive chronotropic and intropic effectsEuropean Journal of Pharmacology, 1976
- Selective stimulation of the parasympathetic preganglionic nerve fibres in the excised and blood-perfused SA node preparation of the dogNaunyn-Schmiedebergs Archiv für experimentelle Pathologie und Pharmakologie, 1973
- Papaverine - induced inhibition of phosphodiesterase activity in various mammalian tissuesLife Sciences, 1971
- Inhibition of cyclic-3?,5?-nucleotide-phosphodiesterase as a possible mode of action of papaverine and similarly acting drugsNaunyn-Schmiedebergs Archiv für experimentelle Pathologie und Pharmakologie, 1970
- A PHARMACOLOGIC AND CLINICAL STUDY OF PAPAVERINArchives of Internal Medicine, 1916