IN-VITRO STUDY OF THE EFFECT OF MIGLITOL ON CARBOHYDRATE DIGESTION AND INTESTINAL METABOLISM IN NORMAL AND NON-INSULIN-DEPENDENT DIABETIC RATS

The effect of miglitol was studied (20 mg/kg body weight), administere d intraduodenally alone or together with maltose, on the absorption an d intestinal metabolism of glucose during its translocation from the l umen of the intestine to the blood, using in vitro perfused preparatio ns of complete small intestine-pancreas, proximal small intestine alon e, or distal small intestine alone, isolated from normal and non-insul in-dependent diabetic rats. in the absence of a luminal administration of maltose in normal rats, the glucose uptake from the vascular perfu sate was greater in the presence (0.52 +/- 0.04 mmol/h) than in the ab sence (0.39 +/- 0.02 mmol/h) of miglitol (p < 0.05). In diabetic rats, no significant variations were observed in glucose uptake from the va scular perfusate as an effect of miglitol, but the glucose uptake in t he presence of this drug was significantly less (p < 0.05) than that o bserved in normal rats. Portal lactate was significantly greater (p < 0.05) in diabetic than in normal rats and, after administration of mig litol, rose in both normal and diabetic rats, the rise being significa ntly greater in normal than in diabetic rats (p < 0.01). When maltose was administered luminally (2 g/kg body weight), the values of portal glucose in both normal and diabetic rats were significantly less in th e presence of miglitol in the complete as well as in the distal and pr oximal small intestine preparations (p < 0.05); the glucose uptake fro m luminal administered maltose was greater in the presence of miglitol in diabetic (p < 0.05) and in normal (p < 0.05) rats except in the co mplete small intestine of normal rats; and no significant differences were observed in portal lactate levels between normal and diabetic rat s in the presence of miglitol. In conclusion, our results show that mi glitol administered luminally at the doses employed here, as well as r educing the transport of glucose from the lumen of the intestine into the blood supply, significantly stimulate intestinal glucose metabolis m.