HYPOTHALAMIC HYPERPHAGIC RATS OVEREAT BITTER SUCROSE OCTA ACETATE DIETS BUT NOT QUININE DIETS

Female rats were made hyperphagic with knife cuts or lesions in the ventromedial hypothalamus (VMH) and their aversion to food made bitter by adulteration with quinine or sucrose octa acetate (SOA) was examined. In short-term choice tests VMH obese rats, as well as controls, strongly preferred a 0.1% quinine diet to a 1.0% SOA diet. Yet, in 24 hr intake tests VMH obese rats overate, relative to controls, the 1% SOA diet, but underate the 0.1% quinine diet. VMH rats in both dynamic and static stages also overate SOA diets in concentrations up to 16%. However, VMH obese rats underate a 1% SOA diet when previously fed a 0.1% quinine diet. The results indicate that the VMH rat's finickiness to quinine diets may not be due to bitter taste alone, but may result from toxic postingestive effects of quinine and the development of a conditioned taste aversion. © 1979.