In vitro evidence for increased facilitation of striatal acetylcholine release via pre- and postsynaptic NMDA receptors in hemiparkinsonian rats |
| |
Authors: | M Marti S Sbrenna K Fuxe C Bianchi L Beani M Morari |
| |
Affiliation: | Department of Experimental and Clinical Medicine, University of Ferrara, Italy. |
| |
Abstract: | The NMDA-evoked acetylcholine release from striatal slices and synaptosomes was investigated in rats subjected to unilateral injection of 6-hydroxydopamine into the substantia nigra. In slices prepared from the striatum contralateral to the lesion, the NMDA-evoked endogenous acetylcholine release was not significant at 10 microM NMDA and maximal at 100 microM NMDA (124 +/- 19%). Conversely, in slices taken from the dopamine-depleted striatum, NMDA was effective even at 10 microM (41 +/- 4%), and at 100 microM (196 +/- 24%) efficacy was nearly doubled. In synaptosomes prepared from the contralateral striatum, NMDA maximally stimulated 20 mM KCl-induced endogenous acetylcholine release at 1 microM (66 +/- 5.1%), with lower concentrations (0.01-0.1 microM) being ineffective. Conversely, in synaptosomes prepared from the dopamine-depleted striatum, NMDA maximally enhanced the K+/--evoked acetylcholine release at 0.1 microM (118 +/- 12.4%). Concentration-response curves of NMDA-evoked acetylcholine release in sham-operated rats could be superimposed on those observed in the contralateral striatum of the 6-hydroxydopamine-lesioned animals. The present data support the view of an increased glutamatergic regulation of striatal acetylcholine release via pre- and postsynaptic NMDA receptors during Parkinson's disease. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|