2.3. Biochemical parameters
The plasma glucose levels were determined using Glutest Neo Super (Sanwa Chemical Co. Kanagawa, Japan) just before and 4 hours after the administration of OSI-906 or the vehicle. Serum insulin levels were determined using an insulin kit (Morinaga Institute of Biological Science, Yokohama, Japan). The glycogen content in the liver was determined using a Determiner-GL-E Kit (Wako Pure Chemical Industries). The serum glutamic pyruvic transaminase (GPT), free fatty acid (FFA), and triglyceride (TG) levels were assayed using enzymatic methods (Wako Pure Chemical Industries).