Development of obesity in diabetic mice pair-fed with lean siblings.

Investigated the role of hyperphagia in the obesity of the diabetic mouse, C57BL/6J/db/db. Ingestion patterns and the amount of food for 25 diabetic mice were controlled by yoking their food intake to that of 16 nonobese siblings obtaining their food by barpressing. Over a period of 6 wks, young (initial ages were 28 days) pair-fed diabetic Ss accumulated 42% more body weight and approximately 5 times more extractable carcass lipid than did their siblings. Weight gain and absolute levels of carcass fat were reduced in food-restricted diabetic Ss compared with db Ss on unrestricted food intake. However, carcass fat as percentage of wet carcass weight was virtually identical in the restricted and unrestricted db rats (47.6 vs 49.6%). From these results it is concluded that the heightened adiposity of the diabetic mouse does not require hyperphagia for its expression and thus represents a metabolic obesity. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)