H2 RECEPTOR ACTIVITY

EFFECT IN ISOLATED RABBIT HEART

Abstract

… Histamine can stimulate the heart by directly interacting with cardiac histamine
receptors. In the present study we have investigated the H2
receptor activity in isolated rabbit
heart. Cimetidine, a specific H2
receptor antagonist was used. The isolated heart was mounted
in langendroff apparatus. The heart was perfused at a constant pressure with oxygenated
Ringer‘s Locke solution. H2
receptor antagonist produces negative inotropic effect in the
presence of histamine. This indicates that H2
receptors are present in rabbit heart, and plays a
role in mediation of positive inotropic effect produced through CAMP by histamine.