Is tumor necrosis factor α a trigger for the initiation of endometrial prostaglandin F2α release at luteolysis in cattle?
Is tumor necrosis factor α a trigger for the initiation of endometrial prostaglandin F2α release at luteolysis in cattle?
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DOI：
10.1095/biolreprod62.5.1109
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发表时间：
2000-05-01
影响因子：
3.6
通讯作者：
Okuda, K
中科院分区：
文献类型：
--
作者：
Miyamoto, Y;Skarzynski, DJ;Okuda, K
确定肿瘤坏死因子α的生理意义为了研究肿瘤坏死因子α（TNF-α）在调节牛子宫内膜促黄体生成前列腺素（PC）F-2 α释放中的作用，研究了TNF-α对离体子宫内膜组织分泌PGF（2 α）的影响，并与催产素（OT）的作用进行了比较。测定发情周期中牛子宫内膜中TNF α特异性受体的存在。子宫内膜切片（20-30毫克）取自发情周期的六个阶段（发情期：第0天;早期I：第2-3天;早期II：第5-6天;中期：第8-12天;晚期：第15-17天;卵泡期：第19-21天），通过卵巢和子宫的肉眼检查确定，暴露于TNF α（0.06-6 nM）和/或OT（100 nM），OT在卵泡期和发情期刺激PGF（2 α）输出（P < 0.001），但在黄体晚期不刺激。另一方面，TNF α对PGF（2 α）分泌的刺激作用不仅在卵泡期，而且在黄体晚期也有黄体晚期子宫内膜组织同时暴露TNF-α组与对照组比较差异有显著性（P < 0.001），（0.6nM）和OT（100 nM）对PGF（2 α）输出的刺激作用高于单独的TNF α或OT的作用（P < 0.05）。在整个发情周期中观察到TNF α与牛子宫内膜的特异性结合。TNF-α受体浓度在黄体早期I期低于其它各期（P < 0.01）。子宫内膜的解离常数（K-d）值在发情周期中是恒定的。总体结果使我们假设TNF α可能是牛黄体溶解开始时子宫内膜输出PGF（2 α）的触发因素。
To determine the physiological significance of tumor necrosis factor alpha (TNF alpha) in the regulation of luteolytic prostaglandin (PC) F-2 alpha release by the bovine endometrium, the effect of TNF-alpha on PGF(2 alpha) output by the endometrial tissues in vitro was investigated and compared with the effect of oxytocin (OT), Furthermore, the presence of specific receptors for TNF alpha in the bovine endometrium during the estrous cycle was determined. Endometrial slices (20-30 mg) taken from six stages of the estrous cycle (estrus: Day 0; early I: Days 2-3; early II: Days 5-6; mid-: Days 8-12; late: Days 15-17; and follicular: Days 19-21), as determined by macroscopic examination of the ovaries and uterus, were exposed to TNF alpha (0.06-6 nM) and/or OT (100 nM), OT stimulated PGF(2 alpha) output at the follicular stage and at estrus (P < 0.001), but not at the late luteal stage. On the other hand, the stimulatory effects of TNF alpha on PGF(2 alpha) output were observed not only at the follicular stage but also at the late luteal stage (P < 0.001), When the endometrial tissues at late luteal stage were simultaneously exposed to TNF alpha (0.6 nM) and OT (100 nM), the stimulatory effect on PGF(2 alpha) output was higher than the effect of TNF alpha or OT alone (P < 0.05). Specific binding of TNF alpha to the bovine endometrial membranes was observed throughout the estrous cycle. The concentration of TNF-alpha receptor at the early I luteal stage was less than the concentrations at other luteal stages (P < 0.01). The dissociation constant (K-d) values of the endometrial membranes were constant during the estrous cycle. The overall results lead us to hypothesize that TNF alpha may be a trigger for the output of PGF(2 alpha) by the endometrium at the initiation of luteolysis in cattle.