β3-AR Background Information Beta 3-adrenergic receptors (b3-ARs) bind cathecholamines (epinephrine, norepinephrine), and primarily regulate lipolysis and thermogenesis in adipose. b3-ARs are present in adipose tissues, heart, and in smooth muscle of bladder, colon, small intestine, and stomach. The human corpus cavernosum exhibits basal b3-AR-mediated vasorelaxant tone and activity is linked to inhibition of the RhoA/Rho-kinase pathway. b3-AR interacts directly with the SH3 domain of Src through proline-rich motifs (PXXP) in the third intracellular loop and the carboxy-terminus.
