Morphological and Enzymological Studies of the Small Intestine Villi of Rats Receiving Diets Containing Different Levels of Protein

摘要

Forty eight one-day old male vistar rats were kept in 3 groups on isocaloric diet, with normal (control), 1.5 percent higher or lower raw protein (T1) and (T2). After 31 d these were sacrificed and samples were taken from proximal and distal duodenum, jejunum and ileum for morphological and enzymological investigations. All villous parameters (villous height, villous width and crypt depth) increased (P<0.05) in T1 and decreased in T2 in most parts of the small intestine compared with the control group. In T1group leaf-like and tongue like villi increased (P<0.05) but bridge like villi decreased. In T2 group the results were reversed. Brush border total leucine amino peptidase and lipase activity increased in T1 and decreased in T2. Therefore, it seems that protein content of the food can change shape and size of the villi and enzyme activity and, therefore, will lead to changes in the absorption capacity of the small intestinal mucosa.