2.8. Insulin and Oral Glucose Tolerance Tests

For insulin tolerance tests, mice deprived of food for 1 h received an intraperitoneal injection of insulin (0.75 units/kg body weight; Actrapid, Novo Nordisk) and blood glucose levels were determined 0, 15, 30 and 60 min after injection. Oral glucose tolerance tests were performed on age-matched mice fasted for 16 h, as previously described (Foretz et al., 2010). Blood glucose levels were determined 0, 20, 40, 60, 90 and 120 min after the oral administration of glucose (3 g/kg body weight). Blood glucose concentration was determined with a glucometer (Roche Diagnostics).