Heterogeneity of guinea pig papillary muscle revealed by systematic variations in the upstroke of the action potential.
D000200:Action Potentials; D000818:Animals; D006168:Guinea Pigs; D006329:Heart Conduction System / Q000502:physiology; D008846:Micromanipulation; D009132:Muscles / Q000502:physiology*; D009206:Myocardium / Q000166:cytology*; D010210:Papillary Muscles