Comparison of Highly Inbred Diabetic and Nondiabetic Lines in the Upjohn Colony of Chinese Hamsters

Eighteen Chinese hamsters, each from two highly inbred lines XA (glucosurie) and M (aglucosuric), were studied with regard to their insulin and glucagon reserves, liver and epididymal fat pad enzymes, and kidney glycosidases. Reciprocal perturbation in pancreatic insulin and pancreatic and stomach glucagon was found in the diabetic XA line, and the degree of disturbance increased with the severity of hyperglycémie. Depression in glucokinase and elevation in phosphenolpyruvate carboxykinase were observed in the livers of all XA animals, whereas decreases in hepatic pyruvate klnase and 6-phosphogluconate dehydrogenase occurred only in XA animals with prolonged diabetes. The levels of these and other enzymes were found to be normal in the epididymal fat pad of the XA animals. Difference in lactate dehydrogenase isozyme distribution was detected in both liver and fat pad between XA and M lines and was attributed to genetic variance. The XA animals showed an elevated level of plasma N-acetyl-β-glucosaminidase but had a similar level of this enzyme in the kidney as the M line, α- and β-galactosidase are significantly depressed in the kidney of the XA animals, whereas αand β-glucosidase are not. Thus, reciprocal disturbances in tissue insulin and glucagon reserves are present in spontaneous diabetes in the Chinese hamsters, and the deviant levels of enzymes in such tissues as liver and kidney may contribute to the manifestation of hyperglycemie and diabetic complications.