Garrett W M, Mack S O, Rohan R M, Guthrie H D
Germplasm and Gamete Physiology Lab, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA.
J Reprod Fertil. 2000 Mar;118(2):235-42.
In situ hybridization was used on frozen tissue sections with digoxigenin-labelled antisense riboprobes to inhibin/activin alpha and beta(A) subunits to determine whether inhibin/activin subunit mRNA expression was associated with development of growing, steroidogenically active follicles during follicle recruitment after ovulation. Cell proliferation-associated nuclear antigen Ki-67 protein and cytochrome P450 aromatase expression in granulosa cells were determined immunohistochemically and used as markers for granulosa cell proliferation and steroidogenesis, respectively, on days 3, 5 and 7 after the onset of oestrus. The amounts of inhibin/activin alpha and beta(A) subunit mRNA and P450 aromatase protein were greater (102, 93, and 238%, respectively; P < 0.05) in medium than in small non-atretic follicles and were positively correlated with Ki-67 and with each other. Inhibin/activin alpha and beta(A) mRNA, P450 aromatase, and Ki-67 in granulosa cells were reduced by 66-83% (P < 0.001) in atretic follicles compared with non-atretic follicles. In addition, inhibin/activin alpha and beta(A) mRNA and P450 aromatase in small (1-2 mm) non-atretic follicles decreased (P < 0.05) between day 3 and day 7 independently of morphological or biochemical signs of atresia. The pattern of inhibin/activin subunit mRNA expression supports the notion that activin and inhibin have roles in growth and steroidogenesis in follicle recruitment during the early luteal phase of the oestrous cycle.
使用地高辛配体标记的抗义核糖探针，对抑制素/激活素α和β（A）亚基的冷冻组织切片进行原位杂交，以确定在排卵后卵泡募集期间，抑制素/激活素亚基mRNA表达是否与正在生长、具有类固醇生成活性的卵泡的发育相关。在发情开始后的第3、5和7天，通过免疫组织化学方法测定颗粒细胞中与细胞增殖相关的核抗原Ki-67蛋白和细胞色素P450芳香化酶的表达，并分别将其用作颗粒细胞增殖和类固醇生成的标志物。抑制素/激活素α和β（A）亚基mRNA以及P450芳香化酶蛋白的含量在中等大小卵泡中比在小的非闭锁卵泡中更高（分别为102%、93%和238%；P<0.05），并且与Ki-67呈正相关，且它们之间也呈正相关。与非闭锁卵泡相比，闭锁卵泡中颗粒细胞的抑制素/激活素α和β（A）mRNA、P450芳香化酶以及Ki-67减少了66%-83%（P<0.001）。此外，在第3天到第7天之间，小的（1-2毫米）非闭锁卵泡中的抑制素/激活素α和β（A）mRNA以及P450芳香化酶减少（P<0.05），且与闭锁的形态学或生化特征无关。抑制素/激活素亚基mRNA表达模式支持这样一种观点，即激活素和抑制素在发情周期黄体早期卵泡募集过程中的生长和类固醇生成中发挥作用。
