[ 125i ] icyp , a radiolabeled beta-adrenergic antagonist , proved to be an excellent probe to identify these receptors in kidney slices in that specific [ 125i ] icyp binding was 1 ) saturable , 2 ) competed stereoselectively by the agonist isoproterenol and the antagonist propranolol , and 3 ) competed by agonists in a classical rank order of potency for beta 1-adrenergic receptors ( isoproterenol greater than epinephrine congruent to norepinephrine ) .
C0014563
epinephrine
C0028351
norepinephrine