Cardiac beta-adrenoceptors and adenylyl cyclase activity in rabbit heart during conditions of altered sympathetic activity.

Chronic (2 weeks) guanethidine treatment of rabbits depleted left ventricular noradrenaline and increased sarcolemmal beta-receptor density and protein yield. Total adenylyl cyclase activity was unchanged. Chronic sinoaortic denervation did not affect ventricular catecholamines and only marginally reduced beta-receptor numbers.