Peculiaritiesof lipid peroxidationрrocesses in jejunum at resections of different volumes of liver parenchyma

Abstract

Introduction. Resections of large volumes of liver parenchyma are complicated by postresection portal hypertension, which leads to structural and functional changes in the organs of the basin portal hepatic vein. The features of the remodeling of the jejunum structures and the features of the processes of lipid peroxidation after resection of different volumes of liver parenchyma were not adequately investigated.

The aim of the study – to learn the features of lipid peroxidation processes in the jejunum of experimental animals after resection of different volumes of liver parenchyma.

Research Methods. The studies were performed on 36 white male rats, which were divided into 3 groups. The first group consisted of 12 intact experimental animals (control), 2nd – 12 animals, which removed the left side lobe of the liver, which was 31.5% of its parenchyma, 3rd – 12 rats after resection of the left and right lateral lobes, that is 58, 1% of liver parenchyma. One month after the beginning of the experiment, euthanasia of rats was performed by bloodletting under conditions of thiopental anesthesia. In quantitative evaluation of lipid peroxidation processes, the content of diene conjugates and active products of thiobarbituric acid in the wall jejunum homogenates were determined. Sections from the jejunum were fixed in a 10% neutral formalin solution, and after conducting, the ethyl alcohol of increasing concentration was placed in paraffin. Histologic sections 5–7 мm thick after deparaffinization were stained with hematoxylin-eosin, for van Gizon, Mallory, Weigert, and toluidine blue. Gistostereometrically there were determined the relative volumes of damaged endothelial cells, epithelial cells, smooth myocytes, relative volume of stroma in the muscle. A correlation analysis was carried out between biochemical and histostereometric indices with the definition of the coefficient (r) of correlation. Quantitative values were processedstatistically.

Results and Discussion. It was established that in conditions of the simulated experiment one month after the resection of the liver the expressed processes of lipid peroxidation occurred in the intestine. Thus, after removal of 31.5% of the liver parenchyma, the content of diene conjugates increased in 1.9 times after resection of 58.1% of liver parenchyma – 3.4 times, the concentration of active products of tiobarbituric acid, respectively, in 2.1 and 6.7 times. The obtained and analyzed indicators testify that at removal of significant volumes of liver parenchyma processes of peroxide oxidation of lipids, which depend on the removed volume of a liver, are substantially increased. A relative volume of damaged epithelial cells of the mucous membrane of the jejunum in the 2nd group of observations increased in 2.6 times, endothelial cells – 2 times, smooth myocytes – 1.86 times, stroma in the muscle of the jejunum– 12.7%. After resection of 58.1% of liver parenchyma,the investigated morphometric parameters increased by 30.6; 19.0; 11.8 and 2.4 times. Correlation connections between the concentrationlipid peroxidation products and relative volumes of damaged endothelial cells, epithelial cells, smooth myocytes and stroma in the wall of the jejunum were positive and significant and intensified when 58.1% of liver parenchyma were removed and ranged from +0.53 to +0.84,

Conclusions. Lipid peroxidation plays an important role in the adaptive-compensatory processes of the jejunumafter resection of different volumes of liver parenchyma. The degree of morphological changes in the jejunum correlates with the concentration oflipid peroxidation products and depends on the removed volume of liver parenchyma.