GROWTH CHARACTERISTICS, GLUCOSE TOLERANCE AND INSULIN SENSITIVITY OF NEW ZEALAND OBESE MICE

Comparisons were made between New Zealand obese (NZO) and control mice with respect to the following points: (1) the age of onset of obesity, (2) the frequency and severity of glucose intolerance, and (3) the degree of insulin sensivity. Total body composition analyses, intravenous glucose tolerance tests and insulin sensitivity tests were performed on the NZO and control strains. The results indicate that NZO mice have developed a significant chemical obesity by the fourth week of life while excessive body weight does not occur until after the twelfth week. Approximately two-thirds of the NZO mice demonstrate abnormal glucose tolerance tests although the degree of the glucose intolerance is relatively mild. The NZO mice are 4 to 5 times more resistant to insulin-induced convulsions than are the control mice.