Some Effects of CNS Cholinergic Neurons on Memory and ACh Release
The aim of this study is to observe the relationship between the impairment in passive avoidance task induced in rats by the i.p. administration of muscarinic antagonists, scopolamine and methyl-scopolamine, and the changes in acetylcholine (ACh), monoamines output induced by these drugs. Initially we studied the effects of these drugs on the animals’ performance of a step-through passive avoidance task. We then measured the change in ACh and monoamines levels after administration of these drugs using an in vivo brain dialysis technique. Scopolamine was effective in impairing the performance of the passive avoidance task, while methyl-scopolamine did not have clear effects on the performance of the task. With regard to ACh output, scopolamine increased ACh dose-dependently and methyl-scopolamine also affected ACh release. Scopolamine did not affect monoamines release except serotonin.
These data suggest that the accumulation of ACh in the synaptic cleft is involved in the memory deficit induced by scopolamine.
KeywordsGuide Cannula Dark Compartment Muscarinic Antagonist Passive Avoidance Task Retention Trial
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- Damsma G, Westerink BHC, Vries JB, C.J. Van den Berg CJ, Horn AS (1987)Measurement of acetylcholine release in freely moving rats by means of automated intracerebral dialysis. J Neurochem 48: 1523–1528Google Scholar
- Weiner N (1985) Atropine, scopolamine, and related antimuscarinic drugs. In:Goodman and Gilman’s°The Pharmacological Basis of Tbherapeutics: seventh edition. Macmillan Publishing Company, New York, pp130144Google Scholar