Ultrastructural changes in omental resistance artery in women with preeclampsia

Objective: The reduced function that is played by the endothelium has been suggested in the pathophysiologic condition of resistance arteries during preeclampsia. Our aim was to determine whether morphologic changes occur in these arteries in patients with preeclampsia. Study Design: The omental resistance arteries were isolated from 11 women with preeclampsia and 10 normotensive pregnant women; the preparations were analyzed by light and electron microscopy. Results: On light microscopic examination, no differences were apparent between both groups of women in cross-sectional preparations of the omental resistance arteries. However, after electron microscopic examination, characteristic changes were found in the subendothelial region of the resistance arteries from women with preeclampsia compared with specimens from normotensive pregnant women. The thickness of elastic lamina was irregular, and the basement membrane was, in part, incomplete. Thus, the arrangement of the location of endothelial cells was changed in the resistance arteries that were taken from women with preeclampsia. Conclusion: These results indicate that ultrastructural changes develop in the subendothelial region of omental resistance arteries in women with preeclampsia. (Am J Obstet Gynecol 2003;189:216-21.)