ISSN:
1573-6903
Keywords:
Acetylcholine
;
glutamate
;
aspartate
;
muscarinic receptors
;
neostriatum
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract This study investigates the effects of different muscarinic receptor agonists on extracellular glutamate and aspartate concentrations in the rat neostriatum. In vivo intracerebral perfusions were undertaken in the conscious rat using a concentric push-pull cannulae system. Amino acid concentrations in samples were determined by HPLC with fluorometric detection. The intrastriatal perfusion of arecoline, a M1-M2 muscarinic receptor agonist, produced a significant decrease in extracellular [ASP] (45% of decrease) but not in extracellular [GLU]. These effects were blocked by scopolamine, a M1-M2 muscarinic receptor antagonist. McN-A-343, a M1 muscarinic receptor agonist, but not the M2 muscarinic receptor agonist, oxotremorine, produced a significant decrease in extracellular [ASP] (40% of decrease) but not in extracellular [GLU]. The effects of McN-A-343 on extracellular [ASP] were blocked by pirenzepine, a M1 muscarinic receptor antagonist. These results suggest that the decrease in extracellular [ASP] could be mediated, at least in part, by M1 muscarinic receptor activation in the rat neostriatum.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1021906529055
Permalink
