title: The synergism acetylcholine-eserine in the epinephrine induced ventricular automaticity.
abstract: Heart ventricular strips of the rat in Krebs solution were used to test the synergism acetylcholine-eserine. Ventricular automaticity induced by epinephrine 1 10(-6) is inhibited by acetylcholine (a 50% reduction of the automatism is observed with acetylcholine 1,23 10(-8) while four different concentrations of eserine cause an evident potentiation of the effect of acetylcholine (with eserine a 10(-5) the ED50 of acetylcholine is 2,57 10(-14)). It is concluded that the synergism eserine-acetylcholine is a synergism with potentiation and the acetylcholine introduced in the Krebs solution interacts with receptors different from those activated by the acetylcholine which accumulates when cholinesterase is inhibited by eserine.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D004357:Drug Synergism; D004837:Epinephrine / Q000494:pharmacology; D006352:Heart Ventricles / Q000187:drug effects; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D010830:Physostigmine / Q000494:pharmacology*; D051381:Rats
chemical_list: D010830:Physostigmine; D000109:Acetylcholine; D004837:Epinephrine