Role of serotonin receptors in the effect of sertraline on feeding behaviour.

The effect of sertraline, a serotonin (5-HT) uptake inhibitor, on 1 h food intake of food-deprived rats was studied in male rats treated intraperitoneally with 1 and 2.5 mg/kg metergoline, a 5-HT1 and 5-HT2 receptor antagonist, 0.5 mg/kg GR 38032F, a 5-HT3 receptor antagonist, or intracerebroventricularly with 6-hydroxy-dopamine to destroy catecholamine-containing neurons. The feeding-suppressant effect of 10 mg/kg sertraline was not significantly modified by any treatment. At 1 and 2.5 mg/kg metergoline did not significantly modify the reduction in total intake and meal size induced by sertraline in slightly-deprived rats whereas at 1 mg/kg the 5-HT receptor antagonist completely blocked the effect of 1.5 mg/kg d-fenfluramine, a 5-HT releaser and uptake inhibitor. In a runway test, metergoline at 1 but not 2.5 mg/kg significantly attenuated the effect of 10 mg/kg sertraline on starting speed in the first and second trial blocks. Both doses tended to attenuate the effect of sertraline on running speed but the interaction was not significant. The reduction in food intake induced by sertraline was antagonized only by 1 mg/kg metergoline in the last trial block. The bulk of these findings argues against an important role of 5-HT receptors in the effect of sertraline on feeding behaviour.