Adaptive responses to pharmacological inhibition of small intestinal alpha-glucosidases in the rat.

Intestinal adaptation (small intestinal weight and length, weight of the caecum and of the residual colon) to feeding different doses (0-5-50-500 mg/kg bw) of the absorbable, competitive alpha-glucosidase inhibitors BAY m 1099 and BAY o 1248 for three, seven, or 28 days was studied in rats. With the highest dose of either inhibitor, a significant and time dependent growth of the caecum was observed. Under these conditions, caecal tissue polyamine concentrations (spermidine and spermine) were slightly higher after three, unaffected after seven and slightly decreased after 28 days. Comparing the trophic effect both of BAY m 1099 and BAY o 1248 with that of the almost unabsorbed glucosidase inhibitor acarbose in fed rats showed that caecal weight was higher in response to the absorbed compounds than in response to acarbose, while total caecal carbohydrate content was unaffected by the absorbed and about nine fold increased by the unabsorbed inhibitors. These findings suggest that acarbose may partially inhibit bacterial carbohydrate degradation in the caecum.