Stimulation of brush border enzyme activity along the rat small intestine by misoprostol.

The effect of Misoprostol (0.3 mg/kg b.w., orally for four weeks) on the brush border membrane enzyme activity, is studied in growing rats. Misoprostol enhanced stomach and intestine relative weights as well as the mucosal weight of the duodenum and proximal jejunum. In treated rats, disaccharidases, alkaline phosphatase and aminopeptidase enzyme activity were measured in brush border purified fraction throughout the small intestine. Sucrase, maltase, aminopeptidase and alkaline phosphatase specific activities were significantly increased along the small intestine. In the proximal jejunum, sucrase (62%; p < 0.001) and maltase (42%; p < 0.01) activities were significantly greater. Sucrase activity was also significantly (p < 0.001) increased by about 103% in the distal jejunum. There was also a significant (p < 0.05) increment of 32% in the duodenal and ileal alkaline phosphatase activity after treatment. Similarly, aminopeptidase activity was significantly (p < 0.05) higher in duodenum (67%) and jejunum (24%). In conclusion, Misoprostol appreciably increased the ability of the small intestine to perform its digestive functions although further studies will be necessary to examine the cellular and molecular mechanism(s) which may be responsible for these effects.