title: Effect of 7-chloro kynurenic acid on glycine modulation of the N-methyl-D-aspartate response in guinea-pig myenteric plexus.
abstract: The glycine modulation of the N-methyl-D-aspartate (NMDA) response in guinea-pig myenteric plexus was investigated by using D-serine and 7-chloro kynurenic acid as a glycine agonist and antagonist, respectively. D-serine caused a concentration-dependent enhancement of the NMDA response, an effect which was competitively inhibited by 7-chloro kynurenic acid (pA2 = 6.0). In addition, 7-chloro kynurenic acid induced a concentration-dependent, non-competitive inhibition of the NMDA response per se, even in the absence of added D-serine. This inhibition was fully reversed by exogenous D-serine, suggesting that this effect was also due to the occupancy of the glycine site. These results emphasize the usefulness of the guinea-pig myenteric plexus for studying the function of the NMDA receptor complex.
authors.affiliation: Glaxo Research Laboratories, Verona, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Reggiani
authors.forename: G
authors.initials: G
authors.lastname: Maraia
authors.forename: R
authors.initials: R
authors.lastname: Ceserani
authors.forename: G
authors.initials: G
authors.lastname: Gaviraghi
mesh_terms: D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D005998:Glycine / Q000037:antagonists & inhibitors* / Q000502:physiology; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007736:Kynurenic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D008297:Male; D009197:Myenteric Plexus / Q000187:drug effects*; D016202:N-Methylaspartate; D012694:Serine / Q000494:pharmacology
chemical_list: D001224:Aspartic Acid; D012694:Serine; D016202:N-Methylaspartate; D007736:Kynurenic Acid; C057013:7-chlorokynurenic acid; D005998:Glycine