the potency of various ligands to compete for 125i-icyp binding sites followed the order : propranolol greater than isoproterenol greater than epinephrine greater than norepinephrine with apparent kd of 2.0 x 10 ( -9 ) , 3.9 x 10 ( -7 ) , 1.0 x 10 ( -5 ) , and 2.5 x 10 ( -5 ) m , respectively .
C0014563
epinephrine
C0028351
norepinephrine