Estradiol-17beta is produced in bovine corpus luteum.
Estradiol-17beta is produced in bovine corpus luteum.
复制标题
Estradiol-17beta 在牛黄体中产生。
作者：
K. Okuda;Y. Uenoyama;B. Berisha;I. G. Lange;H. Taniguchi;S. Kobayashi;A. Miyamoto;D. Schams
本研究旨在探讨细胞色素P450芳香酶(芳香酶)基因在发情周期牛黄体(CL)中的表达、活性及17β雌二醇(E2)的分泌。用逆转录聚合酶链式反应检测黄体早期、中期、晚期和退化期黄体组织中芳香酶基因的表达。虽然芳香酶在黄体早期和退化阶段的表达显著低于黄体中期和黄体晚期，但在所研究的所有黄体阶段中都检测到了芳香酶基因的表达。此外，培养的黄体中期细胞明显地将外源[(3)H]雄烯二酮转化为雌二醇，芳香化酶抑制剂显著抑制了这一转化。为了研究发情周期中雌激素在CL内的局部释放，进行了CL体外微透析系统(MDS)的研究。采用反相高效液相色谱结合酶免疫分析法检测MDS灌流液中雌二醇的含量。在发情周期中，微透析液中雌二醇的基础释放没有变化。此外，当新鲜制备的黄体中期细胞暴露于雌二醇(10(-14)~10(-9)M)时，雌二醇刺激前列腺素(PG)F(2α)的分泌(P<；0.05)，尽管它不影响孕酮和催产素的分泌。这些结果表明，在整个发情周期中，雌二醇在牛CL中局部产生，提示雌二醇作为一种自分泌/旁分泌因子对CL中PGF(2α)的产生起着调节作用。
The aim of this study was to investigate the expression of cytochrome P450 aromatase (aromatase) mRNA, its activity, and estradiol-17beta (estradiol) secretion in bovine corpus luteum (CL) during the estrous cycle. Expression of aromatase mRNA was examined in CL at the early, mid, late, and regressed luteal stages by using a reverse transcription-polymerase chain reaction. Aromatase mRNA was detected in all luteal stages examined, although aromatase expression was significantly lower during the early and regressed luteal phases compared to the mid and late luteal phases. Moreover, cultured midluteal cells clearly converted exogenous [(3)H]androstenedione into estradiol, and an aromatase inhibitor significantly inhibited this conversion. To characterize the local release of estradiol within the CL during the estrous cycle, an in vitro microdialysis system (MDS) of CL was conducted. Estradiol in MDS perfusate was confirmed by a reverse-phase high-performance liquid chromatography in combination with enzyme immunoassays. Basal release of estradiol from microdialyzed CL did not change during the estrous cycle. Additionally, when freshly prepared midluteal cells were exposed to estradiol (10(-14) to 10(-9) M), estradiol stimulated prostaglandin (PG) F(2alpha) secretion (P < 0.05), although it did not affect progesterone and oxytocin secretion. The overall results indicate that estradiol is produced locally in bovine CL throughout the estrous cycle, and they suggest that estradiol plays a role in regulating PGF(2alpha) production in CL as an autocrine/paracrine factor.