BEHAVIORAL AND AUTONOMIC THERMOREGULATION IN LEAN AND GENETICALLY-OBESE (OB/OB) MICE

The capacity for behavioral thermoregulation was assessed in lean and genetically obese (ob/ob) mice, using operant conditioning. After 30 min at an initial air temperature (Ta) of 0.degree. C, total thermal reinforcements and Ta were greater in ob/ob than lean mice; deep body temperature increased in both genotypes. Without a heater, body temperature in the ob/ob fell markedly in the cold. Behavioral thermoregulation also depended on food intake and test temperature. The capacity for behavioral thermoregulation is thus unimpaired in the ob/ob mouse, unlike that for autonomic thermoregulation, suggesting separate sets of central controls for the 2 thermoregulatory systems.