TRANSIENT EXPRESSION OF THE RECOMBINANT CHICK BRAIN P-2Y1 PURINOCEPTOR AND LOCALIZATION OF THE CORRESPONDING MESSENGER-RNA

Extracellular ATP acts at specific cell surface purinoceptors to elicit a wide range of physiological responses. We have recently isolated a cDNA for a G-protein-coupled P-2 purinoceptor (P-2yl) from chick brain. It has been defined as a P-2Y-like purinoceptor by the rank order of potency of P-2 purinoceptor ligands, determined electrophysiologically in the Xenopus oocyte expression system. Here, we examine the ligand selectivity of this recombinant receptor, expressed transiently in COS-7 cells. The regional distribution of the P-2yl purinoceptor transcript within the one-day-post-hatch chick brain was also 2yl determined. It is widely expressed in the cerebellum and telencephalon and in specific nuclei of the mesencephalon and diencephalon, suggesting a neuronal localization of the P-2yl purinoceptor.