Oxytocin receptors in the primate ovary: molecular identity and link to apoptosis in human granulosa cells
Oxytocin receptors in the primate ovary: molecular identity and link to apoptosis in human granulosa cells
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DOI：
10.1093/humrep/dep467
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发表时间：
2010-04-01
影响因子：
6.1
通讯作者：
Mayerhofer, A.
中科院分区：
文献类型：
--
作者：
Saller, S.;Kunz, L.;Mayerhofer, A.
催产素（OT）是由一些哺乳动物排卵前卵泡和黄体的颗粒细胞（GCs）产生的。OT在卵巢中的作用与黄体生成素、甾体生成和黄体溶解有关。人体外受精（ivf）衍生(h)GCs具有功能性OT受体（OTR），与细胞内Ca2+升高有关，但人颗粒细胞（hGCs）中OT受体的分子特性及其下游后果尚不清楚。RT-PCR、测序和免疫细胞化学鉴定了hGCs中真正的OTR。OT （10 nM-10 μ M）诱导细胞内Ca2+水平升高（Fluo-4测量），这被tocinoic酸（TA; 50 μ M，选择性otr拮抗剂）阻断。otr激活的下游效应包括细胞活力/代谢的浓度依赖性降低，表现为atp水平降低，caspase3/7活性升高（P < 0.05），以及细胞退化的电镜迹象。TA阻止了所有这些变化。免疫反应性OTR见于大的和令人惊讶的小的人类卵巢窦前卵泡的CL和GCs。在恒河猴卵巢中，在婴儿卵巢的原始和生长的初级卵泡以及成年卵巢各发育阶段的卵泡以及CL中检测到免疫反应性OTR，这些结果通过激光捕获显微解剖切除的GCs的RT-PCR分析得到证实。我们的研究在人类和恒河猴的GCs中发现了真正的OTRs。高水平的OT激活导致hgc细胞退化。由于小卵泡的GCs也表达OTRs，因此OT在卵泡发育中可能具有未知的功能。
Oxytocin (OT) is produced by granulosa cells (GCs) of pre-ovulatory ovarian follicles and the corpus luteum (CL) in some mammalian species. Actions of OT in the ovary have been linked to luteinization, steroidogenesis and luteolysis. Human IVF-derived (h)GCs possess a functional OT receptor (OTR), linked to elevation of intracellular Ca2+, but molecular identity of the receptor for OT in human granulosa cells (hGCs) and down-stream consequences are not known.RT-PCR, sequencing and immunocytochemistry identified the genuine OTR in hGCs. OT (10 nM-10 mu M) induced elevations of intracellular Ca2+ levels (Fluo-4 measurements), which were blocked by tocinoic acid (TA; 50 mu M, a selective OTR-antagonist). Down-stream effects of OTR-activation include a concentration dependent decrease in cell viability/metabolism, manifested by reduced ATP-levels, increased caspase3/7-activity (P < 0.05) and electron microscopical signs of cellular regression. TA blocked all of these changes. Immunoreactive OTR was found in the CL and GCs of large and, surprisingly, also small pre-antral follicles of the human ovary. Immunoreactive OTR in the rhesus monkey ovary was detected in primordial and growing primary follicles in the infantile ovary and in follicles at all stages of development in the adult ovary, as well as the CL: these results were corroborated by RT-PCR analysis of GCs excised by laser capture microdissection.Our study identifies genuine OTRs in human and rhesus monkey GCs. Activation by high levels of OT leads to cellular regression in hGCs. As GCs of small follicles also express OTRs, OT may have as yet unkown functions in follicular development.