[The effect of caffeine on action potentials induced by noradrenaline in the depolarized heart ventricle of the rat].
In Rat myocardium depolarized by high external KCl concentration, norepinephrine restores excitability in the form of slow rising electrical responses. Caffein alone does not induce such responses. This result agrees with the hypothesis that caffein reduces the slow inward current in the Rat myocardium. Caffein increases the effects produced by norepinephrine. This suggests an indirect action of the caffein on the calcium permeability mediated by intracellular AMP cyclic level.
D000200:Action Potentials / Q000187:drug effects*; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002110:Caffeine / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D006352:Heart Ventricles / Q000187:drug effects / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology*; D051381:Rats; D012964:Sodium / Q000378:metabolism; D016276:Ventricular Function
D002110:Caffeine; D012964:Sodium; D002118:Calcium; D009638:Norepinephrine
Modifications par la caféine des potentiels d'action induits par la noradrénaline sur le myocarde ventriculaire dépolarisé de rat