Character and features of morphofunctional reactions of renal vessels in rats at chronic poisoning with acetylsalicylic acid
The prevalence and availability of aspirin-containing analgesic products makes them sources of unintentional overdose, and even suicidal admission. Therefore, the toxic effect of salicylates is an important cause of morbidity and mortality. In this case, as a rule, the target body is the kidneys. The purpose of the study was to identify the structural changes in the kidneys in the process of chronic poisoning with acetylsalicylic acid. In an experiment on rats using the histological methods of the study, it was found that chronic poisoning with acetylsalicylic acid leads to severe organ disorders in the kidneys, which are manifested in the form of congestive venous plethora with reactive ascending vasoconstriction of the arterial part of the blood route of the organ with a decrease in its throughput. At the same time there was a thickening of the walls of the vessels, which occurred both at the expense of increasing their tone, and due to edema, which was confirmed by the enlightenment of the cytoplasm of the leiomyocytes of the medial cover and an increase in the distance between the nuclei of adjacent layers of the smooth muscle cells. The endothelium of these arteries looked swollen as evidenced by the protrusion of its nuclei into the lumen of the vessels in the form of a “palisade”. Such changes can be considered as a protective reaction that partially prevents hemodynamic overload of the hemomicrocirculatory channel, known in the scientific literature as the reflex of Kitaev. However, in spite of this, in the process of chronic poisoning with acetylsalicylic acid, the complete compensation of blood circulation in the kidneys does not occur. Prolonged vasoconstriction leads to the tissue ischemia, which may be the cause of the development and progression of functional and dystrophic changes in the structural components of the organ parenchyma as a morphological substrate of renal insufficiency. Confirmation of this can be considered the changes in the glomerular apparatus found during the study, which consisted in the gradual reduction of the total area of nephrons with the simultaneous decrease in the area of capillary glomeruli. Moreover, the decrease in the area of capillary glomeruli occurred more intensively, which led to the expansion of urinary spaces. In the final stage of the experiment, the capillary glomeruli were often in collaptoid condition, their size significantly decreased, and the contours became uneven-hilly. Thus, because of the chronic poisoning by acetylsalicylic acid in the kidneys appears stagnant disturbances of the organ circulation, which cause ascending vasoconstriction in the arterial part of the blood stream of the organ, which subsequently leads to ischemia and dystrophic changes in its parenchyma.