the order of potency for inhibition of binding by beta-adrenergic agonists was : ( - ) isoproterenol ( kd , 0.66 microm ) greater than ( - ) epinephrine ( kd , 4.3 microm ) greater than or equal to ( - ) norepinephrine ( kd , 13.5 microm ) .
C0014563
epinephrine
C0028351
norepinephrine