Oral Glucose Tolerance Test, Insulin, and Glucagon Measurement

Four weeks after surgery, oral glucose tolerance tests (OGTTs) were performed in the FG, Sham, and SG groups. After a 12-h fasting period, 2 g/kg (20% v/v) glucose solution was administered through an oral gavage. Glucose levels were measured by glucometer (Glucocard G-Meter 1810, Menarini Diagnostics, Italy) in blood samples obtained from the tails of rats at 0, 30, 60, 90, and 120 min after administration of a glucose solution. The results were expressed as glucose mg/dl plasma.

Additionally, 4 weeks after surgery insulin was measured in blood samples from the tails of rats, every 15 min for 60 min, after administration of the glucose solution administration. For this, we used an ELISA kit (ALPCO Diagnostics, Salem, NH) according to the manufacturer’s instructions. The area under curve (AUC) was calculated by trapezoidal rule for every parameter in the study.