[Diabetic peculiarity of the ALS-Ay and ALR-Ay strains]

ALS and ALR mice were developed as mouse models of alloxan-induced diabetes. These strains do not show spontaneous onset of diabetes. When an obesity gene (Ay) was introduced to these two strains, severe diabetic conditions occurred spontaneously in the produced ALS-Ay and ALR-Ay strains. These strains were examined body weight gain, food consumption, water consumption, urinary sugar content, ketone body level and blood sugar level, and subjected to glucose tolerance test. As a result, in comparison with ALS mice, male ALS-Ay mice showed no obesity and very low tolerance to the glucose tolerance test performed 24 weeks after birth. The level of insulin secretion was 5.0 microU/ml or less, showing hardly any secretory reaction. On the other hand, female ALS-Ay mice were obese and showed no marked decrease in glucose tolerance. The level of insulin secretion was high, and the secretory reaction was strong. In ALR-Ay strain, both male and female mice were obese and showed diabetic conditions similar to those of ALS-Ay mice, though the severity tended to be lower. The characteristic features of diabetic conditions in these mice suggest that these strains, particularly ALS-Ay, may serve as useful new-type models of diabetes.