Acosta Tomas Javier, Bah Mamadou Bousa, Korzekwa Anna, Woclawek-Potocka Izabela, Markiewicz Wlodzimierz, Jaroszewski Jerzy Jan, Okuda Kiyoshi, Skarzynski Dariusz Jan
Laboratory of Reproductive Endocrinology, Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan.
J Reprod Dev. 2009 Apr;55(2):149-55. doi: 10.1262/jrd.20133. Epub 2008 Dec 24.
To examine whether oxygen (O(2)) and nitric oxide (NO) are temporally associated with the acute changes in luteal function during luteolysis, we determined the real-time changes in the circulating concentrations of progesterone (P4) and nitrite/nitrate (the stable metabolites of NO) and the partial pressure of oxygen (pO(2)) during prostaglandin F(2alpha) (PGF(2alpha))-induced luteolysis in cattle. Catheters for frequent blood sample collection were inserted into the ovarian vein (OV), jugular vein (JV) and aorta abdominalis (AA) in 12 cows on Day 9 of the oestrous cycle (oestrus=Day 0). On Day 10, the cows were randomly divided into two groups and treated with a luteolytic dose of a PGF(2alpha) analogue or saline solution (control). Blood samples were collected at -2, -1, 0, 0.25, 0.5, 0.75, 1 and 2 h and then at 2-h intervals until 12 h after treatment (0 h). Injection of a PGF(2alpha) induced a significant decrease in the concentrations of P4 in OV plasma within 2 h. The decrease in P4 concentrations was preceded by an increase in the NO concentrations in the blood collected from OV, JV and AA. Basal pO(2) was significantly higher in OV blood than in JV blood (P<0.05). PGF(2alpha) injection increased pO(2) in OV blood between 0.5 and 2 h. These results demonstrate that PGF(2alpha) induced an acute increase in pO(2) and NO in the ovarian circulation and suggest that O(2) and NO are involved in the early events of CL regression, including inhibition of P4 secretion and output, in cattle.
为了研究氧气（O₂）和一氧化氮（NO）是否与黄体溶解期间黄体功能的急性变化存在时间上的关联，我们测定了牛在前列腺素F₂α（PGF₂α）诱导的黄体溶解过程中，孕酮（P4）和亚硝酸盐/硝酸盐（NO的稳定代谢产物）的循环浓度以及氧分压（pO₂）的实时变化。在发情周期第9天（发情=第0天），将12头母牛的卵巢静脉（OV）、颈静脉（JV）和腹主动脉（AA）插入用于频繁采集血样的导管。在第10天，将母牛随机分为两组，分别用黄体溶解剂量的PGF₂α类似物或盐溶液（对照）进行处理。在处理前-2、-1、0、0.25、0.5、0.75、1和2小时采集血样，然后在处理后（0小时）每隔2小时采集一次，直至12小时。注射PGF₂α在2小时内导致OV血浆中P4浓度显著降低。P4浓度降低之前，从OV、JV和AA采集的血液中NO浓度升高。OV血中的基础pO₂显著高于JV血（P<0.05）。注射PGF₂α使OV血中的pO₂在0.5至2小时之间升高。这些结果表明，PGF₂α诱导卵巢循环中pO₂和NO急性升高，并提示O₂和NO参与了牛黄体退化的早期事件，包括抑制P4分泌和输出。
