such decreases in receptor activity may reflect reduced ability to interact with biochemical effectors ( e.g. , the beta-adrenergic receptor , rhodopsin ) , reduced affinity for binding agonist ligands ( egf , igf-i , insulin receptors ) or reduced enzymatic activity ( e.g. , tyrosine kinase activity of the insulin or egf receptor ) .
C0001643
beta-adrenergic receptor
C1517880
binding