Changes in Placental NO Levels During Physiological Pregnancy and Pregnancy Complicated with Eclampsia

Tinatin Khetsuriani, Paata Makharashvili, Irakli Mamamtavrishvili, Eka Khurtsidze, Nikoloz Kintraia, Tamar Sanikidze

Chachava Scientific Research Institute of Perinatal Medicine, Obstetrics and Gynecology; Tbilisi State Medical University, Georgia

There are lots of evidences suggesting that various complications of preeclampsia, including vascular reactivity changes, vasospasm and multiorganic pathologies, occur due to the development of pathological changes in maternal vascular endothelium. There has been suggested that nitric oxide deficiency plays significant role in the development of structural and functional changes of vascular endothelium in maternal organism. Proceeding from aforesaid, our research aimed to study changes in placental NO levels during physiological pregnancy and pregnancy complicated with preeclampsia. As it proceeds from the analysis of literary data and the results obtained in our study, lowered free NO levels in placental tissue, detected by us during preeclampsia, may be due to eNOS gene mutation as well as to decreased expression of this enzyme and inhibition of iNOS synthesis. At the same time, significant elevation of nitrosyled hemoglobin (HbNO) levels in placenta during preeclampsia indicates the development of tissue hypoxia. Enhanced generation of HbNO complexes results in restriction of NO physiological function, placental dysfunction and aggravation of fetoplacental circulation deficiency.

Keywords:  placenta, oxidative stress, nitric oxide, preeclampsia