Inhibitory effect of metformin on intestinal glucose absorption in the perfused rat intestine

To investigate the effect of metformin on intestinal glucose absorption, a perfusion study of the intestine was performed in the rat. Male Wistar albino rats (8-weeks old) were used in the present study. The glucose absorption by the perfused intestine (788.1 +/- 81.9 mu mol/30 min) was not changed significantly by the direct addition of metformin (90 mu g/mL) to the perfusing medium (737.0 +/- 118.2 mu mol/30 min) or by intraduodenal metformin (250 mg/kg in saline solution) infusion (772.8 +/- 105.3 mu mol/30 min). In rats orally administered metformin (250 mg/kg) for 5 days, glucose absorption by the perfused intestine (375.0 +/- 164.3 mu mol/30 min) was significantly (P < 0.001) lower than that: in control rats (811.0 +/- 83.1 mu mol/30 min). These results indicate that metformin had a significant effect on the digestive tract, and that metformin treatment exerted an inhibitory effect on intestinal glucose absorption in the rat. BIOCHEM PHARMACOL 59;7:887-890, 2000. (C) 2000 Elsevier Science Inc.