title: Excitation-contraction coupling in the myocardium of hibernating chipmunks.
abstract: In the myocardium of nonhibernating chipmunks, replacing external Ca by Sr markedly prolongs the action potential plateau with an increase in contraction, while in preparations from hibernating animals this procedure inhibits both responses. Pretreatment with 4-aminopyridine causes a prolongation of the action potential plateau by Sr in hibernating animals.
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D005260:Female; D006321:Heart / Q000187:drug effects / Q000502:physiology*; D006605:Hibernation; D066298:In Vitro Techniques; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D012589:Sciuridae / Q000502:physiology*
chemical_list: D002118:Calcium