Abstract: AIM: To study the effect of Exendin-4 on the glucose tolerance and serum glucose level in normal animals. METHODS: The fasting blood glucose concentration was tested at 0, 1, 2, 3, 4 h and 2, 4 week after the first administration of Exendin-4 (0.1, 0.3, 0.9 g kg, 4 weeks, qd) in Wistar rats, taking insulin as positive control.Before intragastric administration 2.5 g kg glucose, Exendin-4 (0.2, 0.6, 1.8 g kg) were subcutaneously injected, then the fasting blood glucose concentration was tested at 0.5, 1, 2 h after the glucose loading.After hypodermic administration of Exendin-4 (0.2, 0.6, 1.8 g kg), half of the mice were subcutaneously administrated 2.5 g kg glucose 15 min later, and the insulin was tested at the end of the experiment. RESULTS: Exendin-4 could not significantly change the fasting blood glucose concentration at different times.The fasting blood glucose concentration was significantly decreased after glucose loading by administration Exendin-4.Exendin-4 could increase the serum insulin concentration remarkably after glucose loading and could not change much without glucose loading. CONCLUSION: The results suggest that the blood glucose regulation of Exendin-4 was related to the concentration of glucose.

Key words: Exendin-4, blood glucose, insulin, hypodermic injection