THE STATE OF THE MUCOUS MEMBRANE OF ILEUM AT RESECTIONS OF DIFFERENT VOLUMES OF LIVER

Abstract

Liver resection is widely used in modern surgical clinics. Removal of large volumes of the liver leads to postresection portal hypertension, which is complicated by bleeding from varicose veins of the esophagus, stomach, rectum, ascites, splenomegaly, secondary hyperspelinism, parenchymal jaundice and portosystemic encephalopathy. The widespread prevalence of this pathology, high mortality from its complications indicates that it is an important medical and social problem.

The aim of the study – to learn the peculiarities of structural changes in the mucous membrane of ileum at resection of different volumes of the liver.

Materials and Methods. The studies were conducted on 45 sexually mature male rats, which were divided into 3 groups. The group 1 consisted of 15 intact animals, 2 – 15 rats after resection of the left lateral part – 31.5 % of the liver parenchyma, 3 –15 animals after removal of the right and left lateral parts of the liver (58.1 %). Euthanasia of experimental animals was carried out by bloodletting in conditions of thiopental anesthesia 1 month after the beginning of the experiment. The ileum was studied histologically, electron microscopically and morphometrically. At electronograms with the same increase in columnar epitheliocytes of the mucousa the number of mitochondria in the electronogram was determined, the number of crysts in the mitochondria, the area of ​​mitochondria, the relative volume of mitochondria, the area of ​​microvilli, the relative volume of endocytosis vesicles in the cytoplasm. Quantitative indicators were processed statistically.

Results and Discussion. It was found that resection of 31.5 % of liver parenchyma did not lead to structural changes of the ileum. Resection of 58.1 % of liver parenchyma was complicated by postresection portal hypertension. Optically, the structural changes in the mucous membrane were characterized by swelling, pronounced enlargement, full-blooded of venous vessels, deformation, thickening of the villi, crypt deepening, dystrophy, necrobiosis, desquamation of epithelial cells, mucoadizations of the glands, perivasal and stromal enlargement of the connective tissue, infiltration of lymphocytes and histiocytes. Electron microscopic columnar epitheliocytes with edema, swollen mitochondria with an enlightened matrix, and destruction of crysts. The nuclei are mostly round-shaped, somewhat enlarged in size, localized at different levels of the cell, in places with lysis of nuclear shell, some nuclei are pycnotically altered. The channels of the endoplasmic net are expanded and vacuolizated in places. There was a decrease in the number of microvilli and their destruction. There was also a decrease in the number of endocytosis vesicles in the cells under study. Quantitative morphological studies of ultrastructures of columnar epitheliocytes revealed that in one month after resection of 58.1 % of liver parenchyma, the number of mitochondria in one electronogram was statistically significantly (p <0.001) decreased by 22.1 %, while the number of crysts in one mitochondria – by 18.7 %. The area of ​​mitochondria of investigated cells was statistically significantly (p <0.01) increased by 10.5 %. The relative volume of mitochondria in the epitheliocytes was reduced by 32.8 % (p <0.001), the area of ​​microvilli – by 26.6 %, and the relative volume of endocytosis vesicles in the cytoplasm of the cells under investigation – by 23.1 %. The obtained data indicate a violation of cellular bioenergetics and disturbance of suction processes.

Conclusions. Removal of significant volumes of liver parenchyma leads to postresection portal hypertension and marked remodeling of the structures of the mucous membrane of ileum, characterized by venous drainage disorder, hypoxia, dystrophic, epithelial cell changes, stromal structures, infiltration and sclerosis, severe lesions and a decrease in the number of ultrastructures that provide bioenergy cells and suction processes. The severity of the structural rearrangement of the structures of the mucosa of ileum depends on the volume of the removed parenchyma of the liver.