In vitro analysis of Ca-antagonistic effects of prenylamine as mechanisms for its cardiac actions.
Ca-antagonistic properties of prenylamine were studied using isolated guinea-pig and canine cardiac preparations. Prenylamine is a weak Ca-antagonist compared to nifedipine, verapamil and diltiazem. Lower doses of prenylamine slightly increased the tension, but higher doses decreased the tension of both the guinea-pig and canine cardiac preparations. It decreased the tension while maintaining the action potential of the normal guinea-pig atrial preparation and decreased both the tension and Ca-action potential of the depolarized guinea-pig atrial preparation. Similar to antiarrhythmic agents, prenylamine also decreased the max dV/dt of the normal guinea-pig atrial action potential.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002118:Calcium / Q000037:antagonists & inhibitors*; D004285:Dogs; D004558:Electric Stimulation; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D009200:Myocardial Contraction / Q000187:drug effects; D011188:Potassium / Q000494:pharmacology; D011299:Prenylamine / Q000494:pharmacology*
D011299:Prenylamine; D007545:Isoproterenol; D011188:Potassium; D002118:Calcium