title: Effects of frequency of contraction and ionic environment on the responses of heart muscle to acetylcholine.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002118:Calcium / Q000502:physiology*; D002415:Cats; D002463:Cell Membrane Permeability / Q000187:drug effects; D004576:Electromyography; D006321:Heart / Q000187:drug effects*; D006325:Heart Atria / Q000187:drug effects; D009119:Muscle Contraction / Q000187:drug effects; D010210:Papillary Muscles / Q000187:drug effects*; D012964:Sodium / Q000502:physiology*; D014666:Vasomotor System / Q000187:drug effects
chemical_list: D001285:Atropine; D012964:Sodium; D000109:Acetylcholine; D002118:Calcium