by competition studies , antibody [ ( 3 ) h ] dihydroalprenolol binding was found to display a specificity and stereoselectivity resembling that of the beta-adrenergic receptor , [ i.e. , ( - ) -isoproterenol > ( - ) -epinephrine > ( - ) -norepinephrine ; alprenolol approximately propranolol > > phentolamine = aloperidol ; and ( - ) isomers of both agonists and antagonists 10-100 times more potent than ( + ) isomers ] .
C0014563
epinephrine
C0028351
norepinephrine