Argov Nurit, Sklan David
Faculty of Agriculture, PO Box 12, Hebrew University, Rehovot 76-100, Israel.
Mol Reprod Dev. 2004 Jun;68(2):169-75. doi: 10.1002/mrd.20072.
Lipoproteins in the plasma are the major source of cholesterol obtained by the ovarian theca and granulosa cells for steroidogenesis. In this study, we have identified mRNA expression in bovine theca and granulosa cells of two lipoprotein receptors, low density lipoprotein receptor (LDLr) and very low density lipoprotein receptor (VLDLr) in granulosa cells from small antral follicles through preovulatory follicles and in theca cells from large and medium sized antral follicles. In the corpus luteum (CL) both these receptors were found in the developing and differentiating stages whereas only mRNA for VLDLr was detected in the regression stage. This study also described for the first time, the presence of lipoprotein receptor related protein (LRP8) in granulosa cells from small antral follicles through preovulatory follicles and in theca cells from large and medium sized antral follicles. This may indicate a role of LRP8 in cholesterol delivery to steriodogenic cells. LRP8 was not detected in any of the CL stages. The roles of the LDLr superfamily in lipid transport to ovarian cells and its participation in follicular and CL development and regression is discussed.
血浆中的脂蛋白是卵巢膜细胞和颗粒细胞用于类固醇生成的胆固醇的主要来源。在本研究中，我们通过小腔卵泡到排卵前卵泡的颗粒细胞以及大中腔卵泡的膜细胞，鉴定了牛膜细胞和颗粒细胞中两种脂蛋白受体——低密度脂蛋白受体（LDLr）和极低密度脂蛋白受体（VLDLr）的mRNA表达。在黄体（CL）中，这两种受体在发育和分化阶段均有发现，而在退化阶段仅检测到VLDLr的mRNA。本研究还首次描述了从小腔卵泡到排卵前卵泡的颗粒细胞以及大中腔卵泡的膜细胞中脂蛋白受体相关蛋白（LRP8）的存在。这可能表明LRP8在胆固醇向类固醇生成细胞的传递中起作用。在任何CL阶段均未检测到LRP8。本文讨论了LDLr超家族在脂质向卵巢细胞转运中的作用及其参与卵泡和CL发育与退化的情况。
