Suppression of milk drinking by the combination of fluoxetine and L-5-hydroxytryptophan in rats.

Fluoxetine, an inhibitor of serotonin uptake, when given at 10 mg/kg i.p. enhanced the suppression of milk drinking in non-fasted rats by the serotonin precursor, L-5-hydroxytryptophan, at doses of 10 and 20 mg/kg i.p. These findings support earlier evidence for a role of brain serotonin in the regulation of food intake.