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Updated: May 6, 2026

Single Synapse Indicators of Glutamate Release and Uptake in Acute Brain Slices from Normal and Huntington Mice
Published on: March 11, 2020
Interactions between central glutamatergic, catecholaminergic and cholinergic systems with regard to locomotor
A Svensson1, M L Carlsson, A Carlsson
1Department of Pharmacology, University of Göteborg, PO Box 33031, S-400 33, Göteborg, Sweden.
Abstract:
Following injection of 5µg of the competitive NMDA receptor antagonist AP-5 into the nucleus accumbens, but not following injection of the same dose into the dorsal striatum, a pronounced locomotor stimulation in monoamine-depleted mice was produced; theα-adrenoceptor agonist clonidine (1 mg/kg) administered ip caused a marked potentiation of an intraaccumbens AP-5 (2.5µg) injection.On the other hand, 10µg of AP-5 combined with an ip injection of clonidine (1 mg/kg) caused a marked locomotor stimulation following local application into the dorsal striatum but not following application into the prefrontal cortex. Likewise, in combination with systemically administered clonidine, a substantial locomotor stimulation was observed after application of the muscarine receptor antagonist methscopolamine (62µg) into the dorsal striatum but not into the prefrontal cortex.This study suggests that NMDA receptors in the nucleus accumbens exert an inhibitory influence on locomotor activity. The dorsal striatum may also be involved in such control via NMDA and muscarinic receptors.
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