TY - JOUR T1 - Myenteric ganglionic 5-hydroxytryptamine(1P) signal transmission is mediated via Go protein. JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 518 LP - 524 VL - 277 IS - 1 AU - H Y Wang AU - E Fiorica-Howells AU - H Pan AU - M D Gershon AU - E Friedman Y1 - 1996/04/01 UR - http://jpet.aspetjournals.org/content/277/1/518.abstract N2 - The role of G proteins in mediating the signal transduction of the guinea pig myenteric ganglionic 5-hydroxytryptamine (5-HT)1P receptors was examined. Stimulation of ganglionic membranes with 5-HT in the presence of [35S]GTPgammaS or [alpha 32P]GTP increased guanine nucleotide binding to G(alpha)o but not to G(alpha)s, G(alpha)i or G(alpha)q in a concentration-dependent fashion. Pertussis toxin pretreatment markedly reduce this 5-HT induced response. Similarly, the 5-HT1P receptor-mediated slowly developing and long-lasting depolarizing response is potentiated by GTPgammaS and is inhibited by GDPbetaS or pertussis toxin. The activation of G(alpha)o by 5-HT also was mimicked by the 5-HT1P agonist, 5-hydroxyindalpine and was blocked by the selective 5-HT1P antagonist, N-acetyl-5-hydroxytryptophyl-5-hydroxytryptophan amide. These data provide compelling evidence to suggest that transmembrane signaling for the 5-HT1P receptors in isolated myenteric ganglia is transduced by the trimeric Go protein. ER -