Cherniavskyi A. Morphological features of heart in postnatal period after intrauterine effect of an antigen and Dexamethasone (anatomical and experimental research).

In the dissertation work the main morphological peculiarities of cardiac morphogenesis in postnatal period after intrauterine effect of an antigen and Dexamethasone are determined. Using anatomical and morphometric methods the dynamics of body weight and the absolute and relative weight of the heart of rats from birth up to the 45th day of life in normal condition and after intrauterine injection of staphylococcal toxoid and Dexamethasone were found out. The body weight of newborn animals of both experimental groups was significantly lower compared to the control group. In experimental rats, after the intrauterine administration of Dexamethasone there was a significant decrease of the absolute mass of the heart on the 3rd, 9th, 14th and 21st day after birth. Using morphometric research method, the dynamics of thickness of left and right ventricles and interventricular septum, artery wall, as well as the nuclear-cytoplasmic ratio of cardiomyocytes and the relative area occupied by arterial vessels in the myocardium of the rat heart from the birth up to the 45th day of life in normal condition and after intrauterine injection of staphylococcal toxoid and Dexamethasone solution were determined. It was found that the wall thickness of the left ventricle and interventricular septum of animals that were injected with staphylococcal toxoid in the prenatal period gradually increased from the 1st up to the 45th day of life with a peak of growth on the 5th day (23.01 % and 26.1 % respectively). The dynamics of the increase of right ventricle wall thickness had a wave-like nature with the largest increase on the 3rd and 21st days. The wall thickness of the left and right ventricles and the interventricular septum of heart in experimental group is less during the first three weeks after birth in comparison with the values of the control group after the 21st day, and becomes significantly higher at the 45th day.