The purpose of the present study was to determine the subcellular localization of NAD(P)H oxidase, a reactive oxygen species (ROS)-producing enzyme, in the human placenta at various gestational ages. Ultrastructural enzyme histochemistry for NAD(P)H oxidase, using cerium as a capturing agent, was carried out. Placentas from patients with severe preeclampsia and patients who delivered infants with fetal growth restriction (FGR) were also studied. Electron-dense precipitates indicating NAD(P)H oxidase activity were visible in the microvillous membranes of the placentas, especially on the surface plasma membrane of the syncytiotrophoblast microvilli, after 25 weeks of gestation. The distribution pattern and enzyme intensities were apparently the same among normal, preeclamptic, and FGR placentas. Cytochemical control experiments ensured the specific detection of NAD(P)H oxidase activity. These observations indicated that syncytiotrophoblasts possessed NAD(P)H oxidase activity, and thus ROS-generating activity. Placental NAD(P)H oxidase may play a role in placental lipid peroxidation and the placental defense mechanism.

中文翻译：

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胎盘滋养细胞中酶的组织化学可检测NAD（P）H氧化酶：正常，先兆子痫和胎儿生长受限并发症。

本研究的目的是确定在不同胎龄的人胎盘中NAD（P）H氧化酶（一种产生活性氧（ROS）的酶）的亚细胞定位。以铈为捕获剂，对NAD（P）H氧化酶进行了超微结构酶组织化学分析。还研究了严重先兆子痫患者和分娩有胎儿生长受限（FGR）的患者的胎盘。妊娠25周后，在胎盘的微毛膜上，特别是在合体滋养层微绒毛的表面质膜上，可见指示NAD（P）H氧化酶活性的电子致密沉淀物。正常，先兆子痫和FGR胎盘之间的分布模式和酶强度明显相同。细胞化学对照实验确保了NAD（P）H氧化酶活性的特异性检测。这些观察结果表明合体滋养细胞具有NAD（P）H氧化酶活性，并因此具有ROS产生活性。胎盘NAD（P）H氧化酶可能在胎盘脂质过氧化和胎盘防御机制中起作用。