ICV BETA-HYDROXYBUTYRATE - EFFECTS ON FOOD-INTAKE, BODY-COMPOSITION, AND BODY-WEIGHT IN RATS

This study examined the effect of long-term intracerebroventricular (I CV) infusion of beta-hydroxybutyrate (beta HB) on food intake, diet se lection, body weight, and body composition in rats. Female rats were d ivided into 2 groups and implanted with a 28-day osmotic pump connecte d to a lateral cerebroventricular cannula. One group was infused with artificial cerebrospinal fluid (aCSF) and the other with beta HB for 2 8 days. The rats had free access to both a high-fat/low-carbohydrate a nd a low-fat/high-carbohydrate diet (isocaloric) for the 28-day infusi on period. The group infused with beta HB had a significantly lower bo dy weight gain during the infusion period. Cumulative food intake incr eased in the same manner in both groups. Fat pad weights and carcass l ipid content were significantly higher in beta HB rats, despite the eq uivalent caloric intake in both groups and the decreased body weight. Our observations are in accord with earlier studies indicating that be ta HB infused ICV reduces body weight, but not necessarily food intake . Increased adiposity in association with decreased body weight change in beta HB-infused rats strongly suggests that energy is being partit ioned to fat deposition at the expense of lean tissue growth when keto ne bodies are infused into the cerebroventricles. (C) 1997 Elsevier Sc ience Inc.