Effects of sodium n-dipropylacetate, muscimol hydrobromide and (R,S) nipecotic acid amide on isolation-induced aggressive behavior in mice

An inhibitor of GABA-T (sodium n-dipropylacetate), a GABA agonist (muscimol hydrobromide) and an inhibitor of GABA uptake (R,S) nipecotic acid amide were administered to DBA/2 isolated aggressive mice throughout three successive daily experimental sessions. Aggressive responses, measured by an automated device, were inhibited by the highest doses of the three drugs in each daily session. At the lowest doses, sodium n-dipropylacetate and nipecotic acid amide failed to inhibit aggression in the first session while they were effective in the subsequent sessions. Muscimol was effective in the first session but did not differ significantly from saline in the second and third session. The highest doses of these three drugs did not affect spontaneous motor activity, indicating that the observed drug effects are rather specific.