[Activity of amino- and dipeptidases in the epithelial and subepithelial layers of the small intestine in rats of various age subjected immobilization stress].

Peptidase systems of all the layers of the jejunum and ileum proved to be most sensitive to stress in young rats, whereas in mature and old rats the peptidases' activity was enhanced, particularly in subepithelial layers of the ileum and jejunum. This may be regarded as an adaptive-compensatory response to probable existence of unsplit low-molecular peptides in the subepithelial space due to an augmentation of proteins catabolism and their inflow via stress-damaged membranes of enterocytes.