Insulin tolerance test

In the last week of the experiment, an insulin tolerance test (ITT) was performed on all animals in the respective groups after an 8-hour fast. Insulin (Beijing Xinke Technology Co., Ltd. Beijing, China) was injected subcutaneously (0.75 U/kg body weight). Blood samples were collected from the tail vein at 0, 15, 30, 60 and 120 mins after insulin injection. The blood glucose levels were determined by a glucose meter (Roche, ACCU-CHEK Active). We prepared the lancing device according to the user guide provided, then lanced the rat’s vein of the tail and got a drop of blood. To begin the test, we touched and held the test strip opening to the drop until it had absorbed enough blood.