Valproate enhances fluid consumption suppressed by shock or neophobia, but not by partial satiation or d-amphetamine, in rats.

The effects of sodium valproate (100 and 300 mg/kg) on fluid consumption in water deprived rats were assessed. Drinking was inhibited to approximately equal extents by a water pre-load, by d-amphetamine (1.5 mg/kg), by neophobia and by shock at mild (0.3mA) or moderate (0.5mA) intensities, the latter condition having an enhanced level of deprivation also. At both doses valproate significantly enhanced drinking in the neophobia, mild shock and moderate shock conditions but failed to increase drinking suppressed by pre-load or d-amphetamine. It is concluded that the increases in drinking suppressed by neophobia or shock which valproate induces are due to anxiolytic actions of the drug and not non-specific enhancement of fluid consumption. The present results also constitute a further parallel between the actions of valproate and those of benzodiazepines.