Fig. 2.

Blood glucose concentrations (mg/dl) after intraperitoneal injection of vehicle or sitagliptin (6 mg/kg; time −20 min) in combination with intraduodenal infusions of 4 kcal of MPC or 0.9% NaCl in an oral glucose-tolerance test (2 g/kg of 25% glucose delivered via gavage at time 0). Sitagliptin alone significantly suppressed blood glucose levels compared with vehicle-saline at 20, 40, and 60 min postglucose load. MPC alone significantly suppressed blood glucose levels compared with vehicle-saline at 20 and 40 min postglucose load. When combined, MPC enhanced the glycemic suppressive effects of sitagliptin at 40 min postglucose load. Within a time point, data points with different letters are significantly different from each other (P < 0.05). Data are means ± SE.