Subtypes of NMDA receptor in neurones cultured from rat brain.
The non-competitive N-methyl-D-aspartate (NMDA) antagonist, ifenprodil, discriminates two receptor populations, each of which shows a reciprocal abundance in cultured cortical and cerebellar granule cells. Thus approximately 70% of NMDA-gated membrane current was antagonized with high affinity (IC50 = 1.4 +/- 0.9 microM) in cortical neurones whereas only approximately 20% was antagonized with high affinity (IC50 = 1.3 +/- 0.3 microM) in granule cells. Inhibition curves for CGS 19755 appeared relatively monophasic: this competitive NMDA antagonist had a significantly higher affinity for the granule cell receptor (Ki = 0.8 +/- 0.2 microM) compared with that on cortical neurones (Ki = 2 +/- 0.6 microM). The data suggest that these two antagonists may be of value in identifying the expression of subpopulations of native NMDA receptors in other brain regions.
Priestley
T
T
Merck Sharp and Dohme Research Laboratories, Neuroscience Research Centre, Harlow, Essex, UK.
Ochu
E
E
Kemp
J A
JA
D000818:Animals; D001921:Brain / Q000166:cytology; D001923:Brain Chemistry / Q000502:physiology*; D002478:Cells, Cultured; D005998:Glycine / Q000494:pharmacology; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D010875:Pipecolic Acids / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000378:metabolism*
D010875:Pipecolic Acids; D010880:Piperidines; D016194:Receptors, N-Methyl-D-Aspartate; C053672:selfotel; D016202:N-Methylaspartate; C010739:ifenprodil; D005998:Glycine