Contemporary Understanding оf Etiopatogenesis оf Preeclampsia

Nino Merabishvili, Tamar Sanikidze, Ekaterine Sioridze

Cardiovascular adaptations to pregnancy are essential to assure delivery of oxygen and nutrients to the placenta and fetus. Preeclampsia is a common (5-8% of all pregnancies) disorder of human pregnancy where the normal homodynamic development is compromised. The recent studies ascertain that abnormal migration of trophoblasts early in pregnancy predispose later pathologic changes in vascular endothelium function. Circulating factors produced during reduced perfusion of placenta may impair maternal vascular endothelial function, which in turn will cause such a systemic maternal response as preeclampsia. Endothelial cell dysfunction is considered to play a central role in pathogenesis of preeclampsia. The syndrome is pathophysiologically similar to generalized intravascular inflammatory reaction of maternal body to pregnancy. It is now determined that as a component of non-specific immune defense activated leukocytes produce various reactive oxygen species, such as peroxides, hydroxyl radicals, etc. Normally, when the oxidant-antioxidant system is under appropriate control free radicals are a part of numerous physiologic metabolic processes in the organism. Disbalance of this system induces a vicious circle of a variety of pathologic deviations. Many different clinical, bio-chemical and pathophysiological peculiarities of preeclampsia may be explained by the mechanisms of increased oxidative stress and lipid peroxidation. The relations of the factors, stimulating development of the given pathologic syndrome, to placenta is not yet studied well. Considering the scientific information stated below we are conducting the research aimed to study placental antioxidant system during normal pregnancy and preeclampsia. We are using a complex approach to the processes that take place in placenta so that to link to each other the changes on antioxidant and morphologic levels.

Keywords:   preeclampsia, placenta, endothelium, free radicals, oxidative stress, nitric oxide