雌、孕激素对卵巢切除小鼠子宫骨桥蛋白表达的影响

Effects of estrogen and progesterone on the expression of osteopontin in the ovariectomized mouse uterus

目的探讨雌激素和孕激素对卵巢切除小鼠子宫骨桥蛋白(osteopontin,OPN)表达的影响。方法将性成熟雌性昆明小鼠切除卵巢后分为注射芝麻油(对照组)、173-雌二醇(E组)25 ng/只,孕酮(P组)2mg/只,E 25 ng+P 2mg/只(E+P组),给药3 d后取小鼠子宫;另设单次注射17β-雌二醇25 ng/只(E组)及芝麻油(对照组)后6、12和24h取子宫进行比较。采用免疫组织化学及逆转录-聚合酶链式反应(RT-PCR)法检测小鼠子宫骨桥蛋白的定位及mRNA的转录。结果 (1)OPN的免疫染色主要位于子宫内膜腔上皮、腺上皮和间质。对照组均未检测到OPN。E组OPN的免疫染色最强,E+P组次之,P组最弱。在雌激素作用不同时间,6 h在腺上皮OPN的免疫染色弱阳性,12 h腺上皮、腔上皮OPN的免疫染色阳性,24 h腔上皮、腺上皮和间质均可见较强的OPN免疫染色。(2)E组OPN的mRNA转录水平显著增高,且与E+P组、P组和对照组相比均有显著性差异(P<0.05);E+P组、P组也可促进OPN的mRNA转录,但与对照组相比差异均无显著性(P>0.05)。在雌激素作用不同时间,6 h、12 h和24 h组均可检测到OPN的mRNA转录,与对照组比较均有显著性差异(分别为P<0.05,P<0.05和P<0.01);24 h组OPN的mRNA转录显著增高,与6 h组和12 h组比较均有显著性差异(P<0.01),6 h组与12 h组比较差异无显著性(P>0.05)。结论小鼠子宫内膜的OPN最初是由腺上皮分泌的,雌激素可诱导小鼠子宫内膜OPN的表达,孕激素的作用不明显。

Objective： To investigate the effects of estrogen and progesterone on the expression of osteopontin in the ovariectomized mouse uterus. Methods： Ovariectomized Kunming female mice were injected daily with sesame oil （control group）, 25 ng of 17β-estradiol （E group）, 2 mg of progesterone （P group） and 25 ng E2 ＋2 mg P （E＋P group）, respectively, for 3 consecutive days. 12 hours after the final injection, mouse uteri were collected. In another experiment, a single injection of 17β-estradiol 25 ng or sesame oil was made, and the mouse uteri were collected at 6 h, 12 h and 24 h, respectively, after injection. Immunohistochemistry and reverse transcription polymerase chain reaction （RT-PCR） were used to detect the expression of osteopontin in mouse uterus. Results：（1） Osteopontin was mainly localized in the luminal and glandular epithelium and uterine stroma in treatment group, while the immunostaining of osteopontin in control group was negative. The expression of osteopontin was the highest in E group, second highest in E＋P group, and very weak in P group. （2）At 6 h after 17β-estradiol treatment, the osteopontin positive signal was only weakly localizedin the glandular epithelium. The immunostaining was seen both in luminal and glandular epithelium at 12 h, and a stronger staining in luminal and glandular epithelium and uterine stroma at 24 h. （3）. The expression of osteopontin mRNA in t3 group was significantly higher than that in Eq-P group, P group or control group （P〈0.05）. The transcription of osteopontin mRNA was promoted in E-I-P group and P group, but not significantly higher than that in control group（P〉0. 05）. At different time after 17β- estradiol treatment （6 h,12 h and 24 h）, the transcription of OPN mRNA was detected and significantly higher than that in control group （P〈0.05, P〈0.05 and P〈0. 01, respectively）. The expression of osteopontin mRNA at 24 h after E treatment was significantly higher than that at 6 h and 12 h （P〈0.01）. The expression of osteopontin mRNA at 6 h and 12 h was roughly same （P〉0.05）. Conclusions： Mouse endometrial osteopontin is first secreted by glandular epithelium, and estradiol can induce the expression of osteopontin in the mouse endometria.