Wijayagunawardane Missaka P B, Gabler Christoph, Killian Gary, Miyamoto Akio
Department of Animal Science, University of Peradeniya, Peradeniya, Sri Lanka.
Biol Reprod. 2003 Oct;69(4):1341-6. doi: 10.1095/biolreprod.103.017327. Epub 2003 Jun 11.
Tumor necrosis factor (TNF) alpha is an important physiological mediator of cell-to-cell communication. Recent observations suggest that TNFalpha is involved in the control of reproductive functions. The present study examined the role of TNFalpha in the secretion of factors involved in regulating smooth muscle contraction, such as prostaglandin E2 (PGE2), prostaglandin F2alpha (PGF2alpha), endothelin-1 (ET-1), and angiotensin II (Ang II), as it was in the original by the cow oviduct at different stages of the estrous cycle using an in vitro microdialysis system. Expression of mRNA for TNFalpha and its receptors (TNFalpha-R) was also evaluated. For microdialysis, the lumen of a portion (length, 10 cm) of the each oviductal segment was implanted with a dialysis capillary membrane, and TNFalpha (100 ng/ml) was infused for 4-8 h during a 16-h incubation period. The microdialysis system maintains cell-to-cell integrity and cell-to-cell communication, and it enables real-time observation of physiological changes in the luminal release of different substances. Concentrations of PG, ET-1, and Ang II in 4-h fractions were measured using second-antibody enzyme immunoassays. Infusion of TNFalpha stimulated oviductal secretion of PG, ET-1, and Ang II during the follicular and postovulatory stages, but not during the luteal stage. Expression of TNFalpha, TNFalpha-R type I, and TNFalpha-R type II mRNA was detected in the bovine oviduct by reverse transcription-polymerase chain reaction. High expression of both TNFalphaR types and ligands was detected during the follicular and postovulatory stages, whereas low expression was detected during the luteal stage. The results of the present study provide, to our knowledge, the first direct evidence that TNFalpha stimulates PG, ET-1, and Ang II secretion and that up-regulation of the TNFalpha system occurs in the cow oviduct during the periovulatory period. In conclusion, the TNFalpha system may optimize the release of contraction-related substances and modulate local contraction to regulate the oviductal transport of the gametes and embryo.
肿瘤坏死因子（TNF）α是细胞间通讯的重要生理介质。最近的观察结果表明，TNFα参与生殖功能的调控。本研究利用体外微透析系统，研究了TNFα在发情周期不同阶段对牛输卵管分泌调节平滑肌收缩相关因子（如前列腺素E2（PGE2）、前列腺素F2α（PGF2α）、内皮素-1（ET-1）和血管紧张素II（Ang II））的作用。还评估了TNFα及其受体（TNFα-R）的mRNA表达。对于微透析，在每个输卵管段的一部分（长度10 cm）管腔内植入透析毛细管膜，并在16小时的孵育期内注入TNFα（100 ng/ml）4 - 8小时。微透析系统维持细胞间的完整性和细胞间通讯，并能实时观察不同物质在管腔内释放的生理变化。使用二抗酶免疫测定法测量4小时馏分中PG、ET-1和Ang II的浓度。在卵泡期和排卵后期，注入TNFα刺激输卵管分泌PG、ET-1和Ang II，但在黄体期则不然。通过逆转录-聚合酶链反应在牛输卵管中检测到TNFα、I型TNFα-R和II型TNFα-R mRNA的表达。在卵泡期和排卵后期检测到两种TNFαR类型及其配体的高表达，而在黄体期检测到低表达。据我们所知，本研究结果首次直接证明TNFα刺激PG、ET-1和Ang II的分泌，并且在围排卵期牛输卵管中发生TNFα系统的上调。总之，TNFα系统可能优化收缩相关物质的释放并调节局部收缩，以调节输卵管对配子和胚胎的运输。
