Studies with the mutation, diabetes, in the mouse

The findings suggest a defect in the peripheral utilization of insulin rather than in the synthesis and release of the hormone from the pancreas in man, and causes metabolic disturbances in homozygous mice resembling diabetes mellitus in man.

Abstract

The mutation, diabetes (db), that occurred in the C57BL/Ks strain of mice is a unit autosomal recessive gene with full penetrance, and causes metabolic disturbances in homozygous mice resembling diabetes mellitus in man. Abnormal deposition of fat at 3 to 4 weeks of age is followed by hyperglycemia, polyuria and glycosuria. The diabetic condition appears to develop in two stages. In the early stage, there are marked increases in the levels of plasma insulin, the rates of lipogenesis, gluconeogenesis, and glucose oxidation, and there is a reduction ofβ-cell granules in the islet of Langerhans with other changes suggestive of a compensating adaptation to increased insulin demand. On the other hand, the late stage is characterized by a near normal level of circulating insulin, a marked decrease in glucose utilization but with a continued high rate of gluconeogenesis. These findings suggest a defect in the peripheral utilization of insulin rather than in the synthesis and release of the hormone from the pancreas.