Reserpine-induced supersensitivity and the proliferation of cardiac beta-adrenoceptors.

Chronic reserpine pretreatment resulted in an increase in the basal developed force generated by papillary muscles isolated from the right ventricle of the rabbit. In addition, supersensitivity to the inotropic effects of isoproterenol and a concomitant increase in beta-adrenoceptor number were demonstrated. These results indicate that reserpine-induced supersensitivity is not only associated with alterations at sites beyond the level of receptor activation but also at the level of specific postjuctional membrane receptors.