terazosin ( 0.3 mg/kg , i.v . or less ) did not show any significant effect on clonidine induced bradycardia during electrical stimulation of cardiac sympathetic nerve , whereas prazosin ( 0.3 mg/kg ) , phentolamine ( 0.1 mg/kg ) and yohimbine ( 0.1 mg/kg ) antagonized the effect of clonidine by 37 % , 80.6 % and 63.3 % , respectively .
C0076107
terazosin
C0032912
prazosin