Long-term actions of d-fenfluramine in two rat models of obesity. II. Responses to stress.

In the previous study (part I), we reported that a 28-day regimen of d-fenfluramine administered via osmotic pump sustained weight reductions in normal weight and obese rats without depleting brain 5-HT. Peripheral actions of d-fenfluramine were also examined. Here we extend those findings to night-time observations and to stressful conditions. This treatment regimen had no effects on night-time concentrations of insulin, triglycerides or corticosterone or on the stress-induced rise in triglycerides and corticosterone. The thermic response to cold was unaltered. Glucose tolerance was enhanced in lean, but not obese rats.