Barañao J L, Hammond J M
Mol Cell Endocrinol. 1986 Mar;44(3):227-36. doi: 10.1016/0303-7207(86)90128-0.
The effect of follicle-stimulating hormone (FSH) on cholesterol biosynthesis was studied using a recently developed serum-free medium for the culture of porcine granulosa cells. Both cell proliferation and progesterone production were shown to be dependent on de novo cholesterol synthesis in studies with an inhibitor of HMG-CoA reductase. Under basal conditions, mevalonate levels appeared to be rate-limiting for steroidogenesis but not for cell growth. FSH treatment increased [1-14C]acetate incorporation into sterols and the intracellular content of free and esterified cholesterol. These effect were not abolished when steroidogenesis was inhibited at the cholesterol side-chain cleavage step. Estradiol also stimulated [1-14C]acetate incorporation into sterols. Quantification of progesterone secretion after blockade of cholesterol synthesis revealed the presence of intracellular pools of precursor sterols which required depletion before progesterone secretion ceased. These pools, which were tentatively ascribed to cholesterol and pregnenolone, were increased in FSH-treated cells. Stimulation of cholesterol biosynthesis may play a fundamental role in FSH action on these cells.
利用最近开发的用于培养猪颗粒细胞的无血清培养基，研究了促卵泡激素（FSH）对胆固醇生物合成的影响。在使用HMG-CoA还原酶抑制剂的研究中，细胞增殖和孕酮生成均显示依赖于从头胆固醇合成。在基础条件下，甲羟戊酸水平似乎是类固醇生成的限速因素，但不是细胞生长的限速因素。FSH处理增加了[1-14C]乙酸掺入甾醇以及游离胆固醇和酯化胆固醇的细胞内含量。当在胆固醇侧链裂解步骤抑制类固醇生成时，这些作用并未消除。雌二醇也刺激[1-14C]乙酸掺入甾醇。在阻断胆固醇合成后对孕酮分泌进行定量分析，发现存在前体甾醇的细胞内池，在孕酮分泌停止之前需要耗尽这些池。这些池暂时归因于胆固醇和孕烯醇酮，在FSH处理的细胞中增加。胆固醇生物合成的刺激可能在FSH对这些细胞的作用中起基本作用。
