Maternal stress decreases steroid aromatase activity in brains of male and female rat fetuses.
Maternal stress decreases steroid aromatase activity in brains of male and female rat fetuses.
复制标题
母体压力会降低雄性和雌性大鼠胎儿大脑中类固醇芳香酶的活性。
DOI：
10.1159/000123410
复制
发表时间：
1982
影响因子：
4.1
通讯作者：
Ward,IL
中科院分区：
文献类型：
--
作者：
Weisz,J;Brown,BL;Ward,IL
测定了17-21天龄雄性和雌性大鼠胚胎下丘脑和杏仁核联合标本的类固醇芳香酶活性。这些胎儿来自正常母亲和暴露在压力环境中的母亲，这种压力会导致男性后代的行为男性化和去女性化失败。在白天的黑暗阶段(维拉诺瓦组，怀孕后第17、18、19、20和21天)采集应激母亲和对照组的组织样本。在光期(好时组，怀孕后17.5天、18.5天、19.5天和20.5天)采集额外的样本。所用的芳香酶测定法是基于与[Lβ-~3H]雄烯二酮孵育时形成的氚水的测定，其灵敏度为每管10-15fmol。在对照组和应激组的胎儿中，芳香酶活性没有性别差异。综合两种性别的数据，发现以下显著影响：(1)怀孕后18、19和20天，应激组的芳香酶活性低于对照组；(2)好时组(对照组)在怀孕后18.5天和20.5天，对照组和应激组的酶活性在怀孕后18.5天和19天至20天之间逐渐下降；(3)应激组胎儿在20天和21天之间酶活性升高。在先前的研究中，大脑中的类固醇芳香酶活性与男性胎儿血液中的睾酮水平之间没有明显的关系。未能发现性别差异或睾丸激素对芳香酶活性的影响可能是由于组织稀释，因为酶活性可能集中在几个离散的核区。在得出任何确定的结论之前，需要测量这些区域的酶活性。
Steroid aromatase activity was measured in homogenates of combined hypothalamic and amygdaloid specimens obtained from 17- to 21-day-old male and female rat fetuses. The fetuses were obtained both from normal mothers and mothers exposed to a regimen of stress that results in a failure of behavioral masculinization and defeminization of male offspring. Tissue samples from stressed mothers and controls were obtained during the dark phase of the day (Villanova group, days 17, 18, 19, 20 and 21 postconception). Additional samples were obtained during the light phase (Hershey group, days 17.5, 18.5, 19.5 and 20.5 postconception). The aromatase assay used, based on the measurement of tritiated water formed during an incubation with [lβ-3H] androstenedione, had a sensitivity of 10–15 fmol per tube. There was no sex difference in aromatase activity in fetuses of either control or stressed mothers. When data from the two sexes were combined, the following sfatistically significant effects were identified: (1) lower aromatase activity in stressed compared with control fetuses on days 18, 19 and 20 postconception, (2) a progressive decline in enzyme activity between days 18.5 and 20.5 postconception in the Hershey group (controls) and between days 19 and 20 in both the control and stressed fetuses in the Villanova group, and (3) an increase in enzyme activity in the stressed fetuses between days 20 and 21. No relationship was evident between steroid aromatase activity in brain and circulating testosterone levels in male fetuses as determined in a previous study. Failure to detect sex differences or an effect of testosterone on aromatase activity could be due to tissue dilution since enzyme activity may be concentrated in a few discrete nuclear regions. Measurement of enzyme activity in these regions is needed before arriving at any definitive conclusions.