Responses of obese-hyperglycemic mice and normal mice to “bound” and crystalline insulin

Abstract

The effects of bovine crystalline insulin and “bound” insulin obtained from human serum on glucose utilization in intact obese-hyperglycemic mice and their nonobese siblings and on their isolated epididymal adipose tissue have been studied. “Bound” insulin showed activity similar to that of crystalline insulin in control mice. It stimulated the incorporation of glucose into diaphragm glycogen in vivo and into epididymal adipose tissue glycogen and fat in intact mice and isolated epididymal fat pads. The utilization of glucose by obese-hyperglycemic mice was depressed when compared to controls in the presence of “bound” or crystalline insulin. In older obese and control mice, their ability to synthesize epididymal adipose fat decreased. The formation of diaphragm glycogen also decreased with age in the obese but not control mice.