催产素对小鼠胚泡着床的影响

Effect of oxytocin on implantation in mice

给予雌性未育成年小鼠皮下注射外源性催产素（ＯＴ），观察不同剂量ＯＴ对小鼠胚泡着床的影响。结果表明：不同剂量ＯＴ对小鼠胚泡着床均有抑制作用；对未着床鼠的黄体细胞形态学观察，各实验组与对照组相比，黄体细胞界限模糊不清，胞浆含量减少，出现核固缩，且呈剂量反映关系；随ＯＴ剂量增加，各组血清中雌二醇（Ｅ２）浓度逐渐升高，而孕酮（Ｐ）的浓度却降低。提示ＯＴ抑制小鼠胚泡着床可能与干扰卵巢黄体细胞的机能导致Ｐ浓度降低有关。

bjectives: To investigate effect of oxytocin(OT) on implantation of mice's blastocyst. Design: The research of anti implantation. Setting: Reproductive Laboratory of Qiqihar Medical College. Methods: Mature female mice were obtained and mated with mature male mice. The vaginal plug was examined next day moring. When the vaginal plugs were found, the mice were randomly divided into 5 groups: control group; OT100 mIU, 400 mIU, 800 mIU and 1 600 mIU groups. Salin and OT at different doses were administrated separately to controls and tested mice via subcutaneous injection until fifth day of pregnancy and killed at twelfth day of pregnancy. The average number of implantation and the percentage of blastocyst implantation were counted and calculated. The concentration of the serum estradiol and progesterone were measured in nonimplantation mice of each group by RIA. The morphology of luteal cells of the nonimplantation mice in each group were surveyed by the method of HE dyeing. Results: Compared control group with experimental groups, implantation of blastocyst was inhibited by various doses of OT (implantation percentage were: control group 75.0%; OT 100mIU 41.7%, P >0.05; OT 400mIU 25.0%, P<0.05;OT 800mIU 18.2%, P<0.001; OT 1 600mIU 9.0%, P <0.001) . The morphology of luteal cells were examined. The boundary lines of the luteal cells was obscure, the content of cytoplasm was declind and the pyknosis was found in the treated mice with different doses of OT. At the same time, the concentrations of estradiol and progesterone in serum were determined. The production of estradiol gradually increased and progesterone decreased as OT dose increased in the experimental groups. Conclusions: The results demonstrated that OT can inhibit implantation in mice via disturbing the function of luteal cells and caused the decrease of concentration progesterone in corpus luteam.