the sum of alpha 1- and alpha 2-adrenoceptors labelled by these selective alpha 1- and alpha 2-adrenoceptor antagonists was about equal to the number labelled by the non-selective alpha-adrenoceptor antagonist [ 3h ] -dihydroergocryptine .
C0001639
alpha 2-adrenoceptors
C0034784
alpha-adrenoceptor