inasmuch as the selective lipophilic alpha-2 adrenoceptor antagonist , yohimbine , but not the polar alpha adrenoceptor antagonist , phentolamine , reversed the mydriatic effects of clonidine and cocaine , these data suggest that centrally located alpha-2 adrenoceptors elicit the above mydriatic response .
C0034784
alpha adrenoceptor
C0001639
alpha-2 adrenoceptors