Pharmacological characterisation of pyrimidinoceptor responses in NG108-15cells

In the present study, the P2Y receptor(s) mediating the effects of the pyri midines UTP and UDP on phospholipase C activation in the mouse neuroblastom a X rat glioma hybrid cell line NG108-15 was investigated. Reverse Transcri ptase-Polymerase Chain Reaction (RT-PCR) analysis detected transcripts for the P2Y(6) and P2Y(2) receptors, but not for P2Y(1) and P2Y(4.) UTP and UDP were equipotent agonists and their effects were partially additive. Surami n, reactive blue 2 and pyridoxal phosphate-6-azophenyl-2',4'disulfonic acid (PPADS) antagonised the phospholipase C response to both UTP and UDP. High micromolar concentrations of adenosine, 2-p-(2-carboxyethyl)phenethylamino -5'-N-ethylcarboxamidoadenosine (CGS-21680), 2',3'-O-isopropylideneadenosin e (iPAdo) and adenosine 3':5'-cyclic monophosphate (3',5'-cAMP) were able t o antagonise the effect of UTP on phospholipase C but not that of UDP. The additivity of the UTP and UDP responses, novel P2 receptor antagonist profi le and the distinguishing action of adenosine may indicate the expression o f a pyrimidine selective P2Y receptor in addition to the P2Y(6) type in the se cells. (C) 2001 Published by Elsevier Science B.V.