Lobb D K, Skinner M K, Dorrington J H
Banting and Best Department of Medical Research, University of Toronto, Ont., Canada.
Mol Cell Endocrinol. 1988 Feb;55(2-3):209-17. doi: 10.1016/0303-7207(88)90136-0.
To test the hypothesis that the cells outside the basal lamina of the follicle secrete paracrine factors that influence the cells on the inside of the follicle, two ovarian cell populations were obtained from diethylstilbestrol-treated rats. Granulosa cells were obtained by extrusion from the follicles and an ovarian cell preparation, termed thecal/interstitial, was derived from the granulosa cell-depleted ovaries. Light microscopy showed that each cell population in culture had distinctive morphologies. Electrophoretic examination of the radiolabeled proteins secreted by the two ovarian cell preparations revealed that each secreted unique protein components into the culture medium. Rat thecal/interstitial cell-conditioned medium promoted [3H]thymidine incorporation into normal rat kidney cell line (NRK) DNA and into bovine granulosa cell DNA. The growth-promoting activity was stable to heating at 70 degrees C for 5 min whereas native fibroblast growth factor (FGF) lost its activity, showing that the factor was not characteristic of FGF. To further characterize the growth-promoting activity thecal/interstitial cell-conditioned medium was concentrated and the proteins separated by size exclusion high performance liquid chromatography. The growth-promoting activity eluted with an apparent molecular weight between 15,000 and 25,000. The finding that thecal/interstitial cells in culture secrete growth-promoting factors suggests that those cells that are in close proximity to the granulosa cells may secrete protein factors that diffuse into the follicular antrum and influence granulosa cell proliferation.
为了验证卵泡基膜外的细胞分泌旁分泌因子影响卵泡内部细胞这一假说，从己烯雌酚处理的大鼠中获取了两种卵巢细胞群体。通过从卵泡中挤出获得颗粒细胞，一种称为卵泡膜/间质的卵巢细胞制剂则取自去除颗粒细胞的卵巢。光学显微镜检查显示，培养中的每种细胞群体都有独特的形态。对这两种卵巢细胞制剂分泌的放射性标记蛋白质进行的电泳分析表明，每种制剂都向培养基中分泌了独特的蛋白质成分。大鼠卵泡膜/间质细胞条件培养基促进了[3H]胸腺嘧啶核苷掺入正常大鼠肾细胞系（NRK）的DNA以及牛颗粒细胞的DNA中。这种促生长活性在70摄氏度加热5分钟后仍保持稳定，而天然成纤维细胞生长因子（FGF）则失去了活性，这表明该因子并非FGF所特有。为了进一步表征这种促生长活性，对卵泡膜/间质细胞条件培养基进行了浓缩，并通过尺寸排阻高效液相色谱法分离其中的蛋白质。促生长活性在表观分子量为15,000至25,000之间洗脱出来。培养中的卵泡膜/间质细胞分泌促生长因子这一发现表明，那些与颗粒细胞紧密相邻的细胞可能分泌蛋白质因子，这些因子扩散到卵泡腔中并影响颗粒细胞的增殖。
