Histamine increases the Ca current in guinea-pig ventricular myocytes.
Histamine prolonged the action potential duration and shifted the plateau in an upward direction in guinea-pig ventricular myocytes. Whole cell voltage clamp experiments revealed that histamine increases the amplitude of the inward Ca current with a slight increase in the outward current. Cimetidine but not mepyramine inhibited the effects of histamine. We suggest that histamine increases the Ca current via the mediation of the H2-receptors.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*
D007473:Ion Channels; D006632:Histamine