Inotropic effects of ranitidine.
The purpose of this controlled study was to study the effect of cimetidine and ranitidine on the myocardium of 8 healthy male volunteers using systolic time intervals. Ranitidine caused a significant decrease in the QS2I, as from 40 min indicating a positive inotropic effect. There were no significant changes in heart-rate or blood-pressure. It is postulated that ranitidine, differing structurally from cimetidine, may have a higher affinity for H2-presynaptic receptors at the sympathetic myocardial junction resulting in an increase in noradrenaline and an increased inotropic effect.
Meyer
E C
EC
Department of Pharmacology, University of Pretoria.
Sommers
D K
DK
van Wyk
M
M
Avenant
J C
JC
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects*; D002927:Cimetidine / Q000494:pharmacology*; D004562:Electrocardiography; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D011897:Random Allocation; D011899:Ranitidine / Q000494:pharmacology*
D002927:Cimetidine; D011899:Ranitidine