Vega M, Johnson M C, Díaz H A, Urrutia L R, Troncoso J L, Devoto L
Institute of Maternal and Child Research, San Borja-Arriaran Clinical Hospital, Santiago, Chile.
Endocrine. 1998 Apr;8(2):185-91. doi: 10.1385/ENDO:8:2:185.
To evaluate the effect of nitric oxide (NO.) in human corpus luteum (CL) function, we investigated the expression and the presence of NO. synthase (NOS) in the human CL and the action of NO. on the in vitro luteal steroid production. The expression of endothelial NOS (eNOS) in early, mid-, and late CL was assessed by reverse transcriptase polymerase chain reaction (RT-PCR) and the immunohistochemical study was performed in human CL histological sections by using monoclonal antibodies (MAbs) against the distinct NOS isoforms. In addition, seven human mid-CLs were enzymatically dispersed, and the cells were cultured with NO. donor compounds. Steroid production was measured in the culture media by specific radioimmunoassay. The results show that the expression of eNOS was highly detected in mid- and early CL, and to a lesser extent, in late CL. Meanwhile, the immunohistochemical study indicated that both isoenzymes of NOS were expressed in mid-human CL, eNOS being the more abundant isoform present. On the other hand, functional studies showed that NO. donors (L-arginine [L-Arg] and sodium nitroprusside) elicited an inhibitory action on steroid synthesis, preferentially on estradiol production by the luteal cell cultures (p < 0.05). In conclusion, the NO-NOS system is present in the human CL, and it may serve as a modulator of the in vitro human luteal steroidogenesis.
为评估一氧化氮（NO.）对人黄体（CL）功能的影响，我们研究了人CL中NO.合酶（NOS）的表达与存在情况以及NO.对体外黄体类固醇生成的作用。通过逆转录聚合酶链反应（RT-PCR）评估早期、中期和晚期CL中内皮型NOS（eNOS）的表达，并使用针对不同NOS亚型的单克隆抗体（MAb）在人CL组织切片上进行免疫组织化学研究。此外，将七个中期人CL进行酶解分散，细胞与NO.供体化合物一起培养。通过特异性放射免疫测定法测量培养基中的类固醇生成。结果显示，eNOS的表达在中期和早期CL中高度检测到，在晚期CL中检测程度较低。同时，免疫组织化学研究表明，NOS的两种同工酶在中期人CL中均有表达，eNOS是存在的更丰富的同工酶形式。另一方面，功能研究表明，NO.供体（L-精氨酸[L-Arg]和硝普钠）对类固醇合成产生抑制作用，优先抑制黄体细胞培养物中雌二醇的产生（p < 0.05）。总之，NO-NOS系统存在于人CL中，它可能作为体外人黄体类固醇生成的调节剂。
