a similar distribution of both alpha 1- and alpha 2-adrenoceptor sites was seen but the distribution of muscarinic acetylcholine sites was markedly different . alpha-adrenoceptors were present predominantly in ventricular muscle whereas muscarinic acetylcholine receptors exhibited a greater density in atrial tissue compared to ventricular muscle .
C0001639
alpha 2-adrenoceptor
C0034784
alpha-adrenoceptors