Cui Sheng, Liu Jia li, Shao Yu jing, Zhang Jian Chao
Department of Animal Physiology, College of Biological Sciences, China Agricultural University, Beijing, PR China.
Reprod Fertil Dev. 2004;16(6):611-6. doi: 10.1071/rd02104.
The present study was designed to investigate the relationship between fetal sheep pituitary oestrogen receptor (ER) alpha expression and changes in fetal and maternal plasma 17beta-oestradiol (E2) concentrations during gestation. The results revealed that immunoreactivity for ER was located in the nuclei and distributed throughout the fetal pituitary gland during gestation. The percentage of ERalpha-positive cells was approximately 2% of the total cell population in female fetuses at Day 60 of gestation, increased to approximately 7% and 13% of the total cell population at Days 90 and 120 of gestation, respectively, and then declined to approximately 10% at birth. The fetal plasma E2 concentrations were approximately 19 and 71 pg mL(-1) at Days 90 and 120 of gestation, respectively, and decreased to 22 pg mL(-1) after birth. In male fetuses, plasma E2 concentrations and the percentage of ERalpha-positive cells were similar to values in female fetuses throughout gestation, except on Day 120 when the plasma E2 level in female fetuses was significantly higher than in male fetuses. These data demonstrate that changes in the percentage of fetal pituitary ERalpha-positive cells parallel fetal plasma E2 concentrations throughout gestation.
本研究旨在探讨妊娠期间胎羊垂体雌激素受体（ER）α表达与胎儿及母体血浆17β-雌二醇（E2）浓度变化之间的关系。结果显示，妊娠期间ER的免疫反应性位于细胞核内，且分布于整个胎儿垂体。妊娠第60天时，雌性胎儿中ERα阳性细胞的百分比约占总细胞数的2%，在妊娠第90天和第120天时分别增至总细胞数的约7%和13%，然后在出生时降至约10%。胎儿血浆E2浓度在妊娠第90天和第120天时分别约为19和71 pg mL-1，出生后降至22 pg mL-1。在雄性胎儿中，整个妊娠期间血浆E2浓度和ERα阳性细胞的百分比与雌性胎儿相似，但在妊娠第120天时，雌性胎儿的血浆E2水平显著高于雄性胎儿。这些数据表明，整个妊娠期间胎儿垂体ERα阳性细胞百分比的变化与胎儿血浆E2浓度平行。
