The intrinsic control of myocardial contraction--ionic factors.

Action Potentials Adenosine Triphosphatases/metabolism Animals Calcium/metabolism,physiology Catecholamines/metabolism,physiology Digitalis Glycosides/pharmacology Extracellular Space/metabolism Heart/drug effects,physiology Humans Ions Membrane Potentials Muscle Contraction Myocardium/enzymology,metabolism Myofibrils/metabolism Potassium/metabolism,physiology Rabbits Rats Sarcoplasmic Reticulum/metabolism Sodium/physiology

Catecholamines Digitalis Glycosides Ions Sodium Adenosine Triphosphatases Potassium Calcium