Dupont E, Labrie F, Luu-The V, Pelletier G
Medical Research Council Group in Molecular Endocrinology, CHUL Research Center, Quebec, Canada.
J Histochem Cytochem. 1991 Oct;39(10):1403-7. doi: 10.1177/39.10.1940311.
17 beta-Hydroxysteroid dehydrogenase (17 beta-HSD) is the enzyme responsible for the formation of all sex steroids in gonadal as well as extragonadal tissues. To obtain more information about the age-specific expression of 17 beta-HSD in the human placenta, we have localized this enzyme by immunocytochemistry at the light microscopic level at different periods of gestation. In the 7- and 9-week-old placenta, immunostaining was detected exclusively in the cytoplasm of the syncytiotrophoblast. Between the tenth and thirteenth weeks of gestation, immunolabeling was also observed in the cytoplasm of the cytotrophoblastic cells, suggesting that these cells could be transiently involved in the biosynthesis of sex steroids. Interestingly, between the fourteenth and twenty-fifth weeks of gestation, 17 beta-HSD was observed in both the cytoplasm and nucleus of the syncytiotrophoblast. The reaction product was much more intense in nuclei than in cytoplasm. During the last trimester of gestation, strong immunocytochemical staining was observed in all the nuclei of the syncytiotrophoblast, the cytoplasm being unstained. The meaning of this nuclear staining for 17 beta-HSD is still unclear and remains to be extensively investigated.
17β-羟类固醇脱氢酶（17β-HSD）是一种负责在性腺及性腺外组织中合成所有性类固醇的酶。为了获取更多关于人胎盘中17β-HSD年龄特异性表达的信息，我们通过免疫细胞化学方法在光镜水平对该酶在妊娠不同时期进行了定位。在7周和9周大的胎盘中，免疫染色仅在合体滋养层细胞的细胞质中检测到。在妊娠第10周至第13周期间，在细胞滋养层细胞的细胞质中也观察到免疫标记，这表明这些细胞可能暂时参与性类固醇的生物合成。有趣的是，在妊娠第14周至第25周期间，在合体滋养层细胞的细胞质和细胞核中均观察到17β-HSD。反应产物在细胞核中的强度远高于细胞质。在妊娠晚期，在合体滋养层细胞的所有细胞核中均观察到强烈的免疫细胞化学染色，而细胞质未染色。17β-HSD这种核染色的意义仍不清楚，有待深入研究。
