the rank orders of the inhibition of 3h-prazosin binding to the membrane preparations of the aorta expressed as ic50 ( the concentration of drugs inhibiting 50 % of maximal specific binding of 3h-prazosin ) were : prazosin greater than ym09538 greater than phentolamine greater than yohimbine greater than phenoxybenzamine greater than labetalol greater than s-596 greater than dibenamine greater than k-351 greater than propranolol greater than hydralazine greater than n-696 for alpha-blockers and i-epinephrine greater than clonidine greater than i-norepinephrine greater than phenylephrine greater than i-isoproterenol for agonists .
C0014563
epinephrine
C0028351
norepinephrine