Costa Amilton P R, Fagundes-Moura Christiane R, Pereira Virginia M, Silva Leonardo F, Vieira M Aparecida R, Santos Robson A S, Dos Reis Adelina M
Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, 31270-901 Belo Horizonte, Brazil.
Endocrinology. 2003 May;144(5):1942-8. doi: 10.1210/en.2002-220787.
The present study was undertaken to investigate the presence of angiotensin-(1-7) [Ang-(1-7)] in the ovary and a possible role for it. Cycling female rats were killed in each phase of the estrous cycle, and ovarian Ang II and Ang-(1-7) were separated by HPLC and measured by RIA. The mean levels of Ang-(1-7) in proestrus and estrus were significantly higher than those in metestrus and diestrus (P < 0.05). Ang-(1-7) was also significantly higher in equine chorionic gonadotropin (eCG)-treated immature rats. Ang-(1-7) induced a significant increase in estradiol and progesterone production (P < 0.05) in the ovary of immature rats (24-25 d old) pretreated with eCG and perfused in a closed circuit system. This effect was blocked by A-779, a specific Ang-(1-7) antagonist (P < 0.05). The present data demonstrate the presence and physiological role of a novel renin-Ang system peptide in the ovary. The higher level of Ang-(1-7) in proestrus and estrus as well as in eCG-treated rats suggests the involvement of this renin-Ang system peptide in pre- and postovulatory events.
本研究旨在调查卵巢中血管紧张素 -（1 - 7）[Ang -（1 - 7）]的存在及其可能的作用。在发情周期的每个阶段处死处于发情周期的雌性大鼠，通过高效液相色谱法分离卵巢中的血管紧张素II（Ang II）和Ang -（1 - 7），并采用放射免疫分析法进行测定。动情前期和发情期的Ang -（1 - 7）平均水平显著高于动情后期和间情期（P < 0.05）。在经马绒毛膜促性腺激素（eCG）处理的未成熟大鼠中，Ang -（1 - 7）水平也显著升高。在经eCG预处理并在封闭循环系统中灌注的未成熟大鼠（24 - 25日龄）卵巢中，Ang -（1 - 7）可显著增加雌二醇和孕酮的分泌（P < 0.05）。这种作用被特异性Ang -（1 - 7）拮抗剂A - 779阻断（P < 0.05）。目前的数据证明了卵巢中一种新型肾素 - 血管紧张素系统肽的存在及其生理作用。动情前期和发情期以及经eCG处理的大鼠中较高水平的Ang -（1 - 7）表明该肾素 - 血管紧张素系统肽参与排卵前和排卵后的事件。
