MK-801 blocked the functional NMDA receptors in identified cerebellar neurons.
In order to clarify the nature of N-methyl-D-aspartate (NMDA) receptors in cerebellum, where heterogeneity of the NMDA receptor has been suggested, we investigated the action of MK-801 on the NMDA-induced [Ca2+]i rise in cultured cerebellar neurons using video-assisted microfluorometry. MK-801 caused a potent and selective blockade of the NMDA-activated [Ca2+]i elevation. The blockade caused by MK-801 was dependent on the presence of NMDA, i.e., use-dependent. There was no difference in the mode of blockade between immunocytochemically identified Purkinje and non-Purkinje cells, although the relative size of the NMDA-induced [Ca2+]i rise was significantly less in Purkinje cells. These results indicate that the NMDA receptors in cultured cerebellar neurons are coupled with the same channels as those in other brain regions.
Yuzaki
M
M
Division of Regulation of Macromolecular Function, Osaka University, Japan.
Kudo
Y
Y
Akita
K
K
Miyawaki
A
A
Mikoshiba
K
K
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002531:Cerebellum / Q000166:cytology / Q000378:metabolism*; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D004357:Drug Synergism; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism*; D011689:Purkinje Cells / Q000378:metabolism; D016318:Quisqualic Acid / Q000494:pharmacology; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*; D013779:Tetrodotoxin / Q000494:pharmacology
D016194:Receptors, N-Methyl-D-Aspartate; D013779:Tetrodotoxin; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D016318:Quisqualic Acid; D002118:Calcium