THE ROLE OF ACCUMBENS GABA-B RECEPTORS IN THE REGULATION OF RAT BEHAVIOR

The specificity of myorelaxant-like effect of baclofen injected to the nucleus accumbens septi was studied in rats pretreated locally with GABA-B receptor antagonist, delta-amino-n-valeric acid (AVA), in behavioural tests. It was found that local injection of AVA (50 and 100 mug) completely antagonized the influence of intra-accumbens injections of baclofen (2.5 and 5 mug per site). AVA was inactive when given alone in the same dose-range. The present data confirm the myorelaxant-like effect of intra-accumbens injections of baclofen, and suggest the involvement of accumbens GABA-B receptors in the action of muscle relaxant drugs. Our study demonstrates important role of GABAergic innervation of the limbic nucleus in the action of muscle relaxant drug.