FEATURES OF MORPHOLOGICAL CHANGES OF THE PLACENTA DURING PREECLAMPSIA

Abstract

Morphofunctional changes in the placenta in case of preeclampsia and the increase in the expression level of the transforming growth factor have a series of regular stages from the formation, strain and disruption of adaptive mechanisms with more pronounced signs of morphological immaturity of the parenchymal and stromal elements of the placenta, especially in the area of syncytiotrophoblast and spiral vessels.
The severity of the preeclampsia course has a correlation relationship with the state of morphofunctional changes in the placenta and changes in the ratio of the pro- and anti-inflammatory interleukins at different stages of preeclampsia progression. Thus, the study showed that in the fetoplacental complex of women with preeclampsia of severe degree there is a profound damage of structural elements as blood vessels of the hemomicrocirculatory bed with impaired rheological properties of blood and syncytiotrophoblast. Common to them was the process in the form of apoptosis. However, the onset of the apoptotic process in the studies had some differences depending on the structure of the fetoplacental complex. In the syncytiotrophoblast, the disappearance of microvilli, cytoplasmic compaction, and the appearance of osmiophilic membrane structures were observed in areas adjacent to nuclei with signs of apoptosis. Endothelial cells, whose nuclei had signs of initial apoptosis, lost intercellular contacts and were separated from unaffected cells. Subsequently, the apoptotic process acquired the same characteristics for all cell populations.
Therefore, generalizing our studies of ultrastructural changes of vascular endothelial cells of the microcirculatory bed of the fetoplacental complex during pregnancy with a physiological course, it is revealed that endothelial cells completely retain their structure and function accordingly.
At preeclampsia in pregnant women, the complex of morphological changes in the placenta is characterized by significant changes in the structural and functional activity of endothelial cells, cell structure disturbance with the development of the initial stage of apoptosis. Studies have shown that lipid peroxidation is activated in the epithelium of syncytiotrophoblast, as indicated by the presence of osmiophilic structures in the cytoplasm of syncytiotrophoblasts.
The degree of clinical manifestation of preeclampsia has a correlation relationship with IL-10 deficiency and with the increase in tumor necrosis factory-α, stimulation of macrophage-protein production that contributes to the change in the ratio of Thl / Th2, which are antagonists and inhibit each other's development. However, the subpopulation of the immune response induction towards antisuppressor, proinflammatory reversal of the local immune system in preeclampsia is evident.