Klantsa M. Features of morphological changes in the liver of rats under conditions of acute and chronic acetylsalicylic acid poisoning

The dissertation presents a theoretical generalization and a new solution to the actual scientific problem of establishing the features of morphological changes in the bloodstream, cells and tissue of rat’s liver under the conditions of experimental modeling of acute and chronic poisoning by acetylsalicylic acid given the state of acid-base balance and blood viscosity. Studies show that the liver parenchyma of intact mature rats consists of hepatocytes with a central round nucleus and cytoplasm of moderate electron density. The venous section of the rat bloodstream has certain specific features: according to the division of the liver into six lobes, they have six partial trunks, which flow into the big venous collector and which opens directly into the caudal vena cava. The largest diameter has the vein of the largest left lobe. Acute poisoning with acetylsalicylic acid at toxic doses is accompanied by a significant decrease in pH and blood viscosity in rats. Under the conditions of chronic poisoning of acetylsalicylic acid after 1 day of the experiment there was a tendency to decrease the investigated parameters of blood, but its severity was much lower compared to acute poisoning. After 3 days from the beginning of chronic intoxication, stabilization of observed indicators and even partial compensation of pH occurred. However, further, the pH again continued to progressively, however, it was not reaching the level reported for acute poisoning. In contrast, blood viscosity, on the contrary, tended to increase. In severe acute acetylsalicylic acid poisoning structural changes occur in rat liver which lead to the slowdown of organ blood flow, tissue ischemia with the development and progression of functional and dystrophic changes in the structural components of the organ, in the course of which there are several stages: early lesions in the form of hydropic dystrophy of hepatocytes (1 day), a period of relative compensation and stabilization (3-7 days) and a period of recovery of the progression of structural changes (14-28 days). During chronic poisoning aspirin for 28 days observation acquired a tendency to increase the length of the venous reservoir liver, while significantly increasing its width and area. Increased swelling of hepatocytes was confirmed by a further increase of the levels of quantitative characteristics. The area of cross section of both hepatocytes and their nuclei increased significantly. At the same time, the area of hepatocytes increased by 20.2%, their nuclei - by 19.5% and cytoplasm - by 20.3% (in all cases, p˂0.05). As a result, nuclear-cytoplasmic ratios decreased by 11.0%.