Leucine treatment (100 mg/kg daily for 5 days) leads to activation of the hepatocyte nuclear system and granular endoplasmic reticulum and to a drastic increase in the number of mitochondria, characterized by polymorphism. In the spleen, Malpighian bodies and periarterial lymphoid sheaths are enlarged, lymphocytes infiltrate the periarterial zone, and the mantle zone is enlarged. In the thymus, the width of the cortical matter shrinks, while that of the medulla increases. The content of lymphocytes in the medulla decreases, while that of Hassal's bodies increases. Unambiguous effects of leucine on the small intestinal morphology (mainly on the villous epithelium) were shown. Goblet cells in the villous epithelium were sharply stenosed because of decreased secretory granules in them.

Objective. To develop a new way to enhance single-layer colonic anastomosis with oksitselanim tissue and to assess its effectiveness in comparison with anastomosis, reinforced by latex tissue adhesive (LTA). Material and methods. The study was performed on 48 white mongrel male rats. Both the groups underwent intersection of the colon with subsequent formation of anastomosis in an «end-to-end» single-row Pirogov-Mateshuk suture that in the control group was strengthened by latex tissue adhesive, and in the experimental group by oksitselanim tissue. The derivation of the experiment was carried out on 3, 7, 14, 30 days. Such parameters of blood as wbc, phagocytic index, phagocytic number, the level of circulating immune complexes, the activity of complement were studied. The swab was taken from the anastomosis zone for bacteriological examination. The presence of effusion, adhesions, abscess, anastomotic narrowing, expansion of the leading department were macroscopically evaluated. The mechanical strength of the anastomosis was determined by pneumohydropression method. The area of tanastomosis was taken for histological examination. Results. The comparison of the morphological patterns of the abdominal cavity, the results of microscopic and bacteriological study suggests a lower expression of local inflammatory changes and bacterial permeability of colonic anastomoses reinforced with «oksitselanim» tissue. The mechanical strength of anastomoses in the experimental group exceeds those in the control group. The comparative analysis of leukocyte counts, phagocytosis, levels of circulating immune complexes and complement activity suggests a more rapid and less intense non-specific inflammatory response in the experimental group. Conclusion. The «oksitselanim» preparation makes it possible to prevent quickly the development of infectious complications with minimal response of the body and provide better conditions for the tissue regeneration after the formation of intestinal anastomosis.