Experimental studies of the small intestine mucosa

Abstract

The problems pertaining to the surgical therapy of the short bowel syndrome have not yet been solved despite numerous methods for the retardation of stool passage and the enlargement of the absorbent small intestinal surface. We therefore developed a model for the cultivation of neomucosa of endogenous origin on the perietal peritoneum of Wistar rats. In 191 young Wistar rats of each sex with a body weight of 200 to 500 grams, a loop of the small intestine was largely blocked off from the intestine with the help of Braun's anastomosis, opened up and thus sewed onto the parietal peritoneum of the laboratory animal. This led to the formation of a tube with two-thirds of the circumference consisting of small intestine and one-third of peritoneum. After the peritoneal part had been over-grown by neomucosa, the original jejunal part was removed and a tube consisting of perietal peritoneum with a muscular portion was formed around the neomucosal island. After another 4-5 months, a mucosal tube with complete neomucosal lining had formed. It was demonstrated by histological, enzyme histochemical and electron microscopy methods that the neomucosa is indeed a functioning small intestinal mucosa. Intragastric administration of a prostaglandin E2 analogue resulted in accelerated neomucosal growth as well as an increase in the height of the villi and the depth of the cryptae and a decrease in the thickness of the granular tissue. Measurements of the accumulation of 14C glucose and its inhibition by ouabain confirmed the active transport of the 14C glucose in the cell of the small intestinal neomucosa. The cultivation of functioning small intestinal mucosa on the perietal peritoneum of rats was thus accomplished.