d-fenfluramine's effects on normal ingestion assessed with taste reactivity measures

The effects of d-fenfluramine on intake and on hedonic responses to taste stimuli in rats were investigated using a modified taste reactivity paradigm. Subjects (n = 15) were first trained to consume a 3% sucrose solution. They were then pretreated with d-fenfluramine (0.3-3.0 mg/kg, i.p.), and tested with access to either 3% sucrose, or a 0.01% quinine HCl solution. In the modified taste reactivity test, chronic oral cannulation was not used; instead, taste reactivity measures were scored during periods of noningestion in a voluntary intake test. d-Fenfluramine reliably reduced both sucrose and quinine consumption, and increased latency to drink at the highest dose. d-Fenfluramine also spared aversive responses to quinine, but reduced positive ingestive responses to sucrose. These results are consistent with an effect of d-fenfluramine to reduce taste palatability, which may, in turn, be an important factor in the effect of this drug on feeding motivation.