However, activation of adenosine-monophosphate activated protein kinase (AMPK) by metformin was proposedto be responsible for the markedlyreducedglucose-stimulatedinsulinrelease fromprimarypancreatic islets [32] andβ-celllines[33].Thus, contradictory to our results, another study showed significant decrease in plasma insulin level after treatment with metformin [34]; this can be attributed to the different diet used to induce diabetes where hypercaloric diet was used leading to hyperinsulinemia in the diabetic rats. Here, INS is linked to diabetes mellitus.