Gawronska B, Stepien A, Ziecik A J
Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland.
Theriogenology. 2000 Feb;53(3):659-72. doi: 10.1016/S0093-691X(99)00265-4.
We have previously shown that the porcine oviduct possesses immunoreactive and functional LH receptors and that LH causes relaxation of the oviduct, especially during the periovulatory stage of estrous cycle. The current studies were undertaken to investigate the effects of estradiol and progesterone on LH receptor protein and LH-stimulated motility of the oviduct in steroid-primed ovariectomized gilts. Twenty-one cross-bred gilts were ovariectomized at 6 m.o. of age. Four weeks later gilts received daily intramuscular injection of either 2 mL corn oil (control n = 4), estradiol benzoate (EB) 1.5 mg (n = 6), progesterone 50 mg (n = 5), or 1.5 mg EB plus 50 mg progesterone (n = 6) for 4 consecutive days. The gilts were slaughtered on Day 5 after the first injection of steroids or vehicle. Rings of isthmus and ampulla were collected from each oviduct and placed in a tissue chamber perfused with Kreb's solution for 60 min. The mechanical activity was recorded for 30 min after LH treatment. Immunoreactivity of LHR in the Fallopian tube sections were detected in the epithelium of the tubal mucosa, smooth muscle cells and the blood vessel endothelium. Western blotting showed that porcine oviducts contain 75, 48 and 45 kDa immunoreactive LH receptor proteins, like the corpus luteum (CL). The lowest receptor expression was found in controls and in gilts treated with estradiol or progesterone. Combined treatment with estradiol and progesterone resulted in a significant increase of LH receptor protein concentrations when compared with control animals. In vitro LH treatment affected oviduct contractility of combined estradiol and progesterone treated gilts but not the oviduct of the remaining groups. It also caused a decrease in amplitude, frequency and areas under the curve (AUC) of ampulla (P < 0.05) and the amplitude and AUC of isthmus (P < 0.001) in combined estradiol and progesterone-primed gilts. These results indicate that estradiol and progesterone together, but not separately, increase LH receptor protein in the porcine oviduct and that combined estradiol and progesterone priming is necessary for LH-induced relaxation of the porcine oviduct.
我们之前已经表明，猪输卵管具有免疫反应性且功能性的促黄体生成素（LH）受体，并且LH会使输卵管松弛，尤其是在发情周期的排卵前后阶段。当前的研究旨在调查雌二醇和孕酮对用类固醇预处理的去卵巢后备母猪输卵管中LH受体蛋白以及LH刺激的输卵管运动的影响。21头杂交后备母猪在6月龄时进行去卵巢手术。四周后，母猪连续4天每天接受肌肉注射2毫升玉米油（对照组，n = 4）、1.5毫克苯甲酸雌二醇（EB，n = 6）、50毫克孕酮（n = 5）或1.5毫克EB加50毫克孕酮（n = 6）。在首次注射类固醇或赋形剂后的第5天屠宰母猪。从每个输卵管收集峡部和壶腹部的环，并置于用克雷布斯溶液灌注60分钟的组织腔室中。在LH处理后记录30分钟的机械活动。在输卵管黏膜上皮、平滑肌细胞和血管内皮中检测到输卵管切片中LHR的免疫反应性。蛋白质印迹法显示，猪输卵管含有75、48和45 kDa的免疫反应性LH受体蛋白，与黄体（CL）一样。在对照组以及用雌二醇或孕酮处理的母猪中发现受体表达最低。与对照动物相比，雌二醇和孕酮联合处理导致LH受体蛋白浓度显著增加。体外LH处理影响了雌二醇和孕酮联合处理的母猪的输卵管收缩性，但不影响其余组的输卵管。它还导致雌二醇和孕酮预处理的母猪壶腹部的振幅、频率和曲线下面积（AUC）降低（P < 0.05），以及峡部的振幅和AUC降低（P < 0.001）。这些结果表明，雌二醇和孕酮共同作用而非单独作用会增加猪输卵管中的LH受体蛋白，并且雌二醇和孕酮联合预处理对于LH诱导的猪输卵管松弛是必要的。
