Microinjection of a glutamate antagonist into the nucleus accumbens reduces psychostimulant locomotion in rats.
In order to study a possible modulatory effect of glutamatergic afferents to the nucleus accumbens (NAC) on psychostimulant-induced locomotion, L-glutamic acid diethyl ester (GDEE), a glutamate antagonist, was injected in the NAC of rats acutely treated with cocaine, amphetamine or caffeine. GDEE at the doses of 5, 10, and 20 micrograms/side significantly reduced locomotion induced by cocaine (20 mg/kg, i.p.). Amphetamine-induced hyperactivity was also reduced by GDEE, whereas caffeine-induced hyperactivity was not significantly decreased by GDEE. This suggests that glutamatergic afferents to the NAC modulate the effects of psychostimulants and also dopamine function in the mesolimbic system.
Division of Preclinical Neuroscience and Endocrinology, Research Institute of Scripps Clinic, La Jolla, CA 92037.
L
L
Pulvirenti
N R
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Swerdlow
G F
GF
Koob
D000661:Amphetamine / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D002110:Caffeine / Q000494:pharmacology; D003042:Cocaine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D018691:Excitatory Amino Acid Antagonists; D005971:Glutamates / Q000494:pharmacology*; D006948:Hyperkinesis / Q000187:drug effects*; D008297:Male; D008845:Microinjections; D009043:Motor Activity / Q000187:drug effects*; D009714:Nucleus Accumbens / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D012686:Septal Nuclei / Q000187:drug effects*
D018691:Excitatory Amino Acid Antagonists; D005971:Glutamates; C011829:glutamic acid diethyl ester; D002110:Caffeine; D000661:Amphetamine; D003042:Cocaine