AIM: To investigate the effects of exendin-4 on glucose level and glucose tolerance in non-
diabetic mice. METHODS: Non-diabetic
mice were divided into exendin-4 and normal saline (NS) groups. After a bolus intraperitoneal administration of 0.1 μg·g -1 exendin-4, glucose levels were tested at 1 h after administration, followed by daily 10 d of
injection and after the injection of 2 wk. Intraperitoneal glucose tolerance test (IPGTT) was performed on d 20 after the cessation. In addition, three different doses of exendin-4 (0.1, 0.2, 0.4 μg·g -1) were injected daily for 3 d and glucose levels were also tested daily during the injection. RESULTS: The glucose level of mice treated with 0.1 μg·g -1 exendin-4 1 h after the injection was significantly lower as comparing to NS treated mice, ((6.2±s 1.3) mmol·L -1 vs (10.6±1.1) mmol·L -1,P<0.01). The average glucose levels were not affected either during the injection or after the cessation. The results of IPGTT also showed no statistical difference between the two groups. Different doses of exendin-4 did not show notable difference in comparing to the NS group. CONCLUSION: The instant effect of exendin-4 on non-
diabetic mice is to decrease glucose level, but daily injection shows no significant influence on glucose level and glucose tolerance.