DIRECT REGULATION OF ACETYLCHOLINE-RELEASE BY N-METHYL-D-ASPARTIC ACID RECEPTORS IN RAT STRIATUM

Citation
Y. Ikarashi et al., DIRECT REGULATION OF ACETYLCHOLINE-RELEASE BY N-METHYL-D-ASPARTIC ACID RECEPTORS IN RAT STRIATUM, Brain research, 795(1-2), 1998, pp. 215-220
Citations number
33
Categorie Soggetti
Neurosciences
Journal title
ISSN journal
00068993
Volume
795
Issue
1-2
Year of publication
1998
Pages
215 - 220
Database
ISI
SICI code
0006-8993(1998)795:1-2<215:DROABN>2.0.ZU;2-H
Abstract
The aziridinium ion of ethylcholine (AF64A), a cholinergic neurotoxin, was injected into the right striatum of a rat. The unilateral injecti on of 10 nmol AF64A reduced the activity of choline acetyltransferase (CAT) and the tissue content of acetylcholine (ACh) in the striatum. T he striatal contents of dopamine (DA), norepinephrine (NE), 5-hydroxyi ndoleacetic acid (5-HIAA) and gamma-aminobutyric acid (GABA) were unch anged. These results suggest that the cholinospecificity in the striat al lesion was induced by the 10 nmol dose of AF64A. The number of N-me thyl-D-aspartic acid (NMDA) receptors in the striatum treated with 10 nmol AF64A was determined by a specific binding assay using /-)-3-(2-c arboxypiperazin-4-yl)propyl-1-phosphonic acid ([H-3]CPP), a selective ligand for NMDA receptors. The number of the NMDA receptors decreased significantly in the injected area. On the other hand, in a microdialy sis using normal rats, the perfusion of 50 mu M NMDA into the striatum increased ACh release. The perfusion of 100 mu M MK801 which is the s pecific and non-competitive NMDA receptor antagonist, decreased the ba sal levels of ACh release and blocked NMDA-elicited ACh release. Taken together, the present results strongly suggest that a population of N MDA receptors exists on cholinergic interneurons within the striatum, and it directly regulates ACh release. (C) 1998 Elsevier Science B.V. All rights reserved.