Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27606, United States.
Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27606, United States.
Anim Reprod Sci. 2018 Aug;195:139-148. doi: 10.1016/j.anireprosci.2018.05.017. Epub 2018 May 19.
The porcine corpus luteum (CL) is NOT sensitive to the luteolytic effects of PGF-2α until days 12-13 of cycle. The control of "luteolytic sensitivity" (LS) of the pig CL to PGF-2α is unknown, but it is temporally associated with macrophage infiltration into the CL. Since macrophages are the predominant source of TNF-α in the porcine CL, in other studies we examined the effects of TNF-α on porcine luteal cells in culture and showed that TNF-α induces LS in vitro. In Experiment 1 of this study possible mechanisms involved in the control of LS were examined, and involved measurement of the protein levels of PTGER2/EP-2, and PTGER3/EP-3 in porcine CL collected before (days 7-10), versus after (day 13), the onset of the LS. In Experiment 2, an examination of potential mechanisms involved in the control of LS by TNF-α, was carried out in which the effects of TNF-α on mRNA and protein expression of EP-2, EP-3 and FP in cultured luteal cells, were examined. The results of Experiment 1 showed that PTGER-3/EP-3 (but not PTGER-2/EP-2) levels decreased in porcine CLs after (day 13) compared to before (day 7-10) LS. In Experiment 2, the data obtained showed that TNF-α decreased PTGER-3/EP-3 and increased PTGFR/FP protein (in EARLY stage CL). In conclusion, these studies suggest a role for PTGER-3/EP-3 in the acquisition of LS, and support the hypothesis that TNF-α from CL macrophages plays a critical role in the control of LS in the porcine CL, by increasing PTGFR/FP, and decreasing PTGER-3/EP-3 protein.
猪黄体（CL）在周期的 12-13 天之前对 PGF-2α 的溶黄体作用不敏感。猪 CL 对 PGF-2α 的“溶黄体敏感性（LS）”的控制尚不清楚，但它与巨噬细胞浸润 CL 有关。由于巨噬细胞是猪 CL 中 TNF-α的主要来源，在其他研究中，我们检查了 TNF-α对猪黄体细胞培养的影响，并表明 TNF-α在体外诱导 LS。在这项研究的实验 1 中，检查了控制 LS 的可能机制，并测量了在 LS 开始之前（第 7-10 天）和之后（第 13 天）收集的猪 CL 中 PTGER2/EP-2 和 PTGER3/EP-3 的蛋白水平。在实验 2 中，检查了 TNF-α控制 LS 的可能机制，其中检查了 TNF-α对培养黄体细胞中 EP-2、EP-3 和 FP 的 mRNA 和蛋白表达的影响。实验 1 的结果表明，与 LS 之前（第 7-10 天）相比，猪 CL 中的 PTGER-3/EP-3（但不是 PTGER-2/EP-2）水平在 LS 之后（第 13 天）降低。在实验 2 中，获得的数据表明 TNF-α降低了 PTGER-3/EP-3 并增加了 PTGFR/FP 蛋白（在早期 CL 中）。总之，这些研究表明 PTGER-3/EP-3 在获得 LS 中起作用，并支持 TNF-α 来自 CL 巨噬细胞在控制猪 CL 中的 LS 中起关键作用的假说，通过增加 PTGFR/FP 并降低 PTGER-3/EP-3 蛋白。
