Positive and negative inotropic action of polarizing current on the frog ventricle.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001001:Anura; D002118:Calcium / Q000502:physiology; D004560:Electricity; D006321:Heart / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D008345:Manganese / Q000494:pharmacology; D008564:Membrane Potentials; D009119:Muscle Contraction; D013779:Tetrodotoxin / Q000494:pharmacology; D016276:Ventricular Function
D008345:Manganese; D013779:Tetrodotoxin; D002118:Calcium