Abstract
Effects of coadministration of gammahydroxybutyrate (GHB) and L-741,741, a selective D4 dopamine receptor antagonist, on agonistic behaviour in male mice. In previous studies, it has been described a potentiation of the antiaggressive effect after coadministration of gammahydroxybutyrate (GHB) and tiapride, indicating the exisence of an interaction between GHB and D2 dopamine receptors. The aim of this study was to examine the possible existence of an interaction between GHBergic and dopaminergic D4 systems. For this purpose, the effect of administration of gammahydroxybutyrate (GHB) and L-741,741 (0.75-3 mg/kg), a selective D4 dopamine antagonist, either alone or in combination, on agonistic behavior elicited by isolation was analized in male mice. Individually housed mice were exposed to anosmic "standard opponents" in a neutral area 30 minutes after the drugs administration, and the encounters were videotaped and evaluated using an ethologically based analysis. No significant differences were found between experimental and control groups in any of the behavioural categories analyzed. These results suggest that GHB does not interact with central dopamine D4 transmission.
