Extrapancreatic effect of glibenclamide: stimulation of duodenal insulin-releasing activity (DIRA) in man.

Experiments were performed in order to study a possible participation of gastrointestinal factors in the insulinotrophic action of glibenclamide in man. Six healthy volunteers received 5 mg glibenclamide in 50 ml saline orally. Biopsies were taken from the duodenal mucosa before and after administration of the drug. The duodenal insulin-releasing activity (DIRA) was assayed in the extracts of the biopsy material by using an in situ pancreas preparation of rat. The corresponding drug, IRI and glucose levels were measured in peripheral blood. The values of IRI correlated with both the prior elevation of DIRA and the increasing levels of the drug in the blood. These data indicate that glibenclamide might stimulate the release of gut factor(s) which, in turn, could possibly sensitize the pancrease response to the drug.