Influence of endotheliopathy of spiral arteries on placental ischemia

Abstract

Recently, worldwide authors have paid particular attention to vascular endothelium in the mother-placenta-fetus system for the understanding of development of vascular network and its normal functioning, possible gestational endotheliopathy. Endothelial dysfunction is important in the development of thrombosis, neoangiogenesis and vascular remodeling, being the key to the development of obstetric and perinatal disorders. The aim of the study was to reveal morphological signs of endotheliopathy in spiral arteries in preeclampsia, which is important for understanding the development of pregnancy complications. Placentas were obtained after delivery from mothers with preeclampsia served as the material for morphological study. A comparison group included cases from women with a physiological course of pregnancy. The morphological structure was studied after proceeding of slides stained with hematoxylin and eosin, and according to van Gieson. Morphometry was used to determine the specific vascular density, specific density of connective tissue, thickness of the walls of the spiral arteries, cross sectional area of spiral arteries, endotheliocyte height, the diameter of the nuclei of endothelial cells, nuclear cytoplasmic relationships in endotheliocytes, relative volume of injured endothelial cells. As results, it was detected, that development of preeclampsia is associated with signs of remodelling of the spiral arteries. Placental spiral arteries in preeclampsia are characterized by a decrease of specific vascular density by 36,49% with a simultaneous increase of specific density of connective tissue by 43,60%, which is accompanied by thickening of the walls of the spiral arteries 2,82 times and reducing of cross sectional area of spiral arteries 1,57 times. The spiral arteries are also found to have proliferation of the endothelium, hypertrophy of the muscular layer, marked enlargement of the perivascular connective tissue with the formation of the so-called fibrous cuff, resulting in the narrowing of the lumen of the vessels, up to their obliteration. Gestational endotheliopathy is characterized by a decrease in the height of endotheliocytes from 6.19±0.07 x10-6 m to 4.78±0.06 x10-6 m, a decrease in the diameter of cells from 3.25±0.02 x10-6 m to 2.97±0.04 x10-6 m, an increase in the relative volume of damaged endotheliocytes from 6.16±0.23% to 47.07 ±3.61%.