NMDA receptors with different sensitivities to magnesium and ifenprodil control the release of [14C]acetylcholine and [3H]spermidine from rat striatal slices in vitro.
KCl (20-100 mM) and N-methyl-D-aspartate (NMDA, 100-1,000 microM) produce concomitant concentration-dependent increases in the release of previously captured [14C]acetylcholine and [3H]spermidine from rat striatal slices in vitro. The effects of NMDA (300 microM) on striatal [14C]acetylcholine and [3H]spermidine release were blocked with equal potencies by the competitive NMDA antagonist CGP 37849, the glycine site antagonist L-689,560, and the NMDA channel blocker dizocilpine. In contrast, although NMDA-evoked [14C]acetylcholine release was antagonized by ifenprodil (IC50 = 5.3 microM) and MgCl2 (IC50 = 200 microM), neither compound antagonized the NMDA-evoked release of [3H]spermidine at concentrations up to 100 microM (ifenprodil) or 1 mM (MgCl2). Distinct NMDA receptor subtypes with different sensitivities to magnesium and ifenprodil therefore exist in the rat striatum.
Nicolas
C
C
Synthelabo Recherche (LERS), Department of Neurochemistry, Rueil-Malmaison, France.
Fage
D
D
Carter
C
C
D015763:2-Amino-5-phosphonovalerate / Q000031:analogs & derivatives / Q000494:pharmacology; D000109:Acetylcholine / Q000378:metabolism*; D000634:Aminoquinolines / Q000494:pharmacology; D000818:Animals; D002250:Carbon Radioisotopes; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology*; D015636:Magnesium Chloride / Q000494:pharmacology; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D010880:Piperidines / Q000494:pharmacology*; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000502:physiology*; D013095:Spermidine / Q000378:metabolism*; D014316:Tritium
D000634:Aminoquinolines; D002250:Carbon Radioisotopes; D010880:Piperidines; D016194:Receptors, N-Methyl-D-Aspartate; D015636:Magnesium Chloride; D014316:Tritium; C064539:2-amino-4-methyl-5-phosphono-3-pentenoic acid; C074617:4-trans-2-carboxy-5,7-dichloro-4-phenylaminocarbonylamino-1,2,3,4-tetrahydroquinoline; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D015763:2-Amino-5-phosphonovalerate; D008274:Magnesium; D000109:Acetylcholine; C010739:ifenprodil; D013095:Spermidine