Lung resection is widely used in modern surgical clinics. Removal of large volumes of lung parenchyma is lead to the development of postresection arterial pulmonary hypertension and cor pulmonale, the pathogenesis of which is complex and multifaceted, complicating the timely diagnosis of pulmonary hypertension and cor pulmonale. In this case, atrial cardiomyocytes were little studied. The purpose of the research: study of features of structural reconstruction of atrial cardiomyocytes in conditions at postresection pulmonary hypertension. Object and methods. The complex of morphological methods investigated the features of structural reсonstruction of the atrial cardiomyocytes of 38 laboratory white adult male rats, which were divided into 3 groups. The 1 group included 15 intact animals, the 2-15 rats with arterial pulmonary hypertension and compensatory cor pulmonale, 3-8 animals with pulmonary hypertension and decompensatory cor pulmonale. Postresection arterial pulmonary hypertension and cor pulmonale were modeled by performing right-sided pulmonectomy in rats. Euthanasia of rats was carried out by bloodletting under thiopental anesthesia 3 months after the beginning of the experiment. Microtome sections of atrium were stained with hematoxylin-eosin, van Gieson, Heidenhein, Mallory, Weigert, toluidine blue, impregnated with silver. The diameters of cardiomyocytes, their nuclei, the nuclear-cytoplasmic relation in these cells, and the relative volumes of damaged cardiomyocytes were morphometrically determined. Histological micropreparations of the atrium of the heart were examined using light and polarization microscopy. Quantitative indicators were processed statistically. Results and discussion. It is established that right-sided pulmonectomy lead to the development of arterial pulmonary hypertension and cor pulmonale. The morphometric parameters of cardiomyocytes atrial of cor pulmonale significantly changed. Thus, the diameter of left atrial cardiomyocytes in the compensated pulmonary heart increased statistically by 8.3 %, and at decompensation by 16.6 %.The diameter of right atrial cardiomyocytes in the compensated cor pulmpnale was statistically significant (p <0.001) increased by 28.6 %, with decompensationby 41.1% (p <0.001), The relative volume of damaged right atrial cardiomyocytes in the compensated cor pulmonale increased by 12.6 rimes (p <0.001) compared with the control index, and at its decompensation – by 19.6 tymes (p <0.001) and left atrial 5,4 and 14 tymes. The structural reconstruction of the atrial cardiomyocytes at cor pulmonale is characterized by hypertrophy, contracture lesions, foci of myocytolysis, lumps, dissociation of muscle fibers, dystrophy, necrobiosis of cells, tissues, disorders of cellular structural homeostasis. Structural changes in cardiomyocytes dominate the right atrium of decompensated cor pulmonale.
«Bulletin of problems biology and medicine» Issue 3 (152), 2019 year, 283-286 pages, index UDK 616.24-089.87-02:616.149-008
