ICV β-hydroxybutyrate: Effects on Food Intake, Body Composition, and Body Weight in Rats

Abstract

Sun, M., R. J. Martin and G. L. Edwards. ICV β-hydroxybutyrate: Effects on food intake, body composition, and body weight in rats. Physiol Behav 61(3) 433–436, 1997.—This study examined the effect of long-term intracerebroventricular (ICV) infusion of β-hydroxybutyrate ( βHB) on food intake, diet selection, body weight, and body composition in rats. Female rats were divided into 2 groups and implanted with a 28-day osmotic pump connected to a lateral cerebroventricular cannula. One group was infused with artificial cerebrospinal fluid (aCSF) and the other with βHB for 28 days. The rats had free access to both a high-fat/low-carbohydrate and a low-fat/high-carbohydrate diet (isocaloric) for the 28-day infusion period. The group infused with βHB had a significantly lower body weight gain during the infusion period. Cumulative food intake increased in the same manner in both groups. Fat pad weights and carcass lipid content were significantly higher in βHB rats, despite the equivalent caloric intake in both groups and the decreased body weight. Our observations are in accord with earlier studies indicating that βHB infused ICV reduces body weight, but not necessarily food intake. Increased adiposity in association with decreased body weight change in βHB-infused rats strongly suggests that energy is being partitioned to fat deposition at the expense of lean tissue growth when ketone bodies are infused into the cerebroventricles.