Effects of low dose-rate irradiation on the glucose metabolism in type II diabetes model mice

We examined the effects of low dose-rate irradiation on the levels of glucose and insulin in the mice. Ten-week-old female type II diabetes model (db) mice were irradiated with gamma-rays at 0.30, 0.70 or 1.2 mGy/h. The level of plasma glucose and the level of plasma insulin was measured. After the irradiation for 24 days, in the control mice, the level of insulin was decreased to 50% of the initial level, while the decrease was significantly less in the irradiated mice. The mice were irradiated for 2 weeks, and then, after one night fast, they were subjected to a glucose tolerance test. In the irradiated mice, the glucose level was gradually increased. In the non-irradiated mice, the glucose level increased rapidly and the level was kept. These results suggest that the low dose-rate irradiation improved the effectiveness of insulin on the insulin metabolisms and the glucose metabolism in the db mice. (c) 2004 Elsevier B.V. All rights reserved.