INHIBITION OF INTESTINAL SUGAR-TRANSPORT BY PHENFORMIN

Abstract

The effect of phenformin on the absorption of D-glucose and D-galactose by hamster and rat intestine, was studied. Phenformin did not affect D-glucose absorption by rat intestine, but it inhibited at 10-3-10-2 M the absorption of D-glucose and D-galactose by hamster intestine. The inhibition was higher when D-glucose was tested. Phenformin also inhibited active accumulation of these sugars by rings of hamster small intestine, in vitro; this effect was greater when D-glucose was utilized. The drug inhibits the O2 uptake in the tissue in the absence or in the presence of added substrate. Phenformin does not act as a specific inhibitor on D-glucose transport, but most likely by its inhibitory effect on mitochondrial respiration.