Wang Yalei, Meng Chenling, Wei Quanwei, Shi Fangxiong, Mao Dagan
College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
Acta Histochem. 2015 Apr;117(3):297-304. doi: 10.1016/j.acthis.2015.03.007. Epub 2015 Mar 26.
Scavenger receptor class B type 1 (SR-B1) preferentially mediates the selective uptake of high density lipoprotein-cholesterol ester and the delivery of cholesterol for steroidogenesis. Although multiple analyses have investigated the function of SR-B1 in the liver, adrenal and ovary, its expression in rat ovary and uterus during the estrous cycle is lacking. In the present study, real-time PCR, western blot and immunohistochemistry (IHC) were used to investigate SR-B1 expression in the rat ovary and uterus during the estrous cycle. The results demonstrated that ovarian SR-B1 expression was in a stage-dependent manner, continuously increased from proestrus and kept elevated during metoestrus, while uterine SR-B1 expression decreased from proestrus to diestrus. To determine whether ovarian and uterine SR-B1 expression were affected by sex steroid hormones, immature rats were treated with 17 β-estradiol (E2), progesterone (P4), or their antagonists from postnatal days 24-26. Results showed that the levels of SR-B1 mRNA and protein were significantly up-regulated by E2 in both the ovary and uterus. IHC results showed that SR-B1 was primarily localized in the oocytes, theca internal cells (T-I) of follicles, interstitial cells (IC) as well as corpus luteum (CL), but not granulosa cells (GC) in the ovary during the estrous cycle. Uterine SR-B1 was highly expressed in the endometrial luminal epithelial cells (LEC) and glandular epithelial cells (GEC) as well as in the circular muscle (CM) cells, and weak staining in stromal cells (SC) through estrous cycle. Taken together, SR-B1 expression in the ovary and uterus across the estrous cycle demonstrate that SR-B1 may be involved in uterine function, follicular development as well as luteal function.
B1型清道夫受体（SR-B1）优先介导高密度脂蛋白胆固醇酯的选择性摄取以及胆固醇向类固醇生成的转运。尽管多项分析研究了SR-B1在肝脏、肾上腺和卵巢中的功能，但缺乏其在大鼠发情周期中卵巢和子宫内表达情况的研究。在本研究中，采用实时聚合酶链反应、蛋白质免疫印迹和免疫组织化学方法研究发情周期中大鼠卵巢和子宫内SR-B1的表达情况。结果表明，卵巢SR-B1的表达呈阶段依赖性，从发情前期开始持续增加，在动情后期保持较高水平，而子宫SR-B1的表达从发情前期到动情间期逐渐降低。为了确定卵巢和子宫SR-B1的表达是否受性类固醇激素的影响，在出生后第24至26天用17β-雌二醇（E2）、孕酮（P4）或其拮抗剂处理未成熟大鼠。结果显示，E2显著上调了卵巢和子宫中SR-B1的mRNA和蛋白质水平。免疫组织化学结果显示，在发情周期中，SR-B1主要定位于卵巢中的卵母细胞、卵泡的内膜细胞（T-I）、间质细胞（IC）以及黄体（CL），但不存在于颗粒细胞（GC）中。子宫SR-B1在整个发情周期中在内膜腔上皮细胞（LEC）、腺上皮细胞（GEC）以及环行肌（CM）细胞中高表达，而在基质细胞（SC）中染色较弱。综上所述，发情周期中卵巢和子宫内SR-B1的表达表明，SR-B1可能参与子宫功能、卵泡发育以及黄体功能。
