임신성 고혈압과 정상 혈압을 보인 임신의 태반에서 면역조직화학 염색을 통해 본 Endothelial Nitric Oxide Synthase의 분포양상 = Immunohistochemical Localization of Endothelial Nitric Oxide Synthase in Normotensive and Preeclamptic Placentas

다국어 초록 (Multilingual Abstract)

Objective; Endothelial isoform of nitric oxide synthase[eNOS] regulates the vascular resistance by producing nitric oxide[NO], endothelium-derived relaxing factor. The purpose of this study was to compare the expression of eNOS by immunohistochemical staining in the placentas and umbilical vessels of preeclamptic pregnancies with that of normotensive pregnancies. Method; Placentas and umbilical vessels were examined from 5 preeclamptic pregnancies and 5 normotensive pregnancies. Frozen sections of umbilical cords, chorionic plate vessels, and terminal villi were immuno-stained with a monoclonal eNOS antibody[H32]. Mann-Whitney U test and Fisher`s exact test were used where appropriate, and p value < 0.05 was taken to be significant. Results; No differences in eNOS immuno-staining in the endothelium of chorionic plate vessels and stem villous vessels were found between preeclamptic and normotensive pregnancies. In the syncytiotrophoblast, eNOS immunostaining appeared diffusely in distribution in both the preeclamptic and normotensive placentas. In contrast, eNOS expression was only observed in the small terminal villous vessels with underlying smooth muscle layer in the preeclamptic placentas[p<0.05]. Conclusion; Increased eNOS expression in terminal villous vessels in preeclampsia may be the result of vascular alterations or damage that take place in the placenta, and may be an adaptive response to the increased resistance and poor perfusion in this pathological pregnancies.