GABA RHO-2 RECEPTOR PHARMACOLOGICAL PROFILE - GABA RECOGNITION SITE SIMILARITIES TO RHO-1

The rho2 receptor for gamma-aminobutyric acid (GABA) induces GABA-gated currents when expressed as a homooligomer in Xenopus oocytes. Rho2 responses display pharmacological profiles similar to those of expressed rho1 receptors, although responses were slower, most agonists were more potent at rho2 and I(m) values for the partial agonist imidazole-4-acetic acid were 7-fold higher. Amino acids important for most aspects of GABA agonist ligand recognition may not be among those that differ between rho1 and rho2, including the 20% amino acid difference in the N-terminal region.