MORPHOLOGICAL CHANGES OF RAT PLACENTA IN DIFFERENT PERIODS OF PREGNANCY UNDER MODELED PREECLAMPSIA

The purpose of the study was to determine the morphological changes of rat placenta in II, III week of pregnancy under modeled preeclampsia. Modeling of preeclampsia was performed in the rats, as follows: lumen of the abdominal aorta below the renal artery was narrowed by the silk tread on the third of its diameter (0.2 mm). The placenta tissue was studied by histological and immunohistochemical methods (AE1/AE3, CD133, Ki-67). The study has shown that in the experimental model of preeclampsia at the end of II, III week of pregnancy the number of glycogen cells in the placenta trophyspongium layer is reduced compared with the control. There was shown sharp dilatation of the blood sinuses and lacuna, sometimes along the events of stasis. The volume of nucleated erythrocytes in fetal capillaries of the labyrinth layer is reduced compared with the control, especially in IIIweek of pregnancy. In the preparations marked by the CD133 marker, unlike to the norm of III week of pregnancy, the visualization of positive endothelial cells is complicated. The study of the preparations marked by Ki-67 marker reveals that the proliferated activity in the hypoxic placenta tissue is sharply reduced. The exception is those blood tubes, to which umbilical blood vessels are finally formed. It can be concluded that due to hypoxia placenta proliferation of placental blood vessels is disturbed that contributes to the disorder of placental blood circulation, reduce its metabolism in complications of pregnancy.