The effect of insulin on intracellular ph and ribosomal protein S6 phosphorylation in oocytes of Xenopus laevis.
The effect of insulin on intracellular ph and ribosomal protein S6 phosphorylation in oocytes of Xenopus laevis.
复制标题
胰岛素对非洲爪蟾卵母细胞内 ph 值和核糖体蛋白 S6 磷酸化的影响。
DOI：
10.1016/0012-1606(84)90176-3
复制
发表时间：
1984
影响因子：
2.7
通讯作者：
Maller,JL
中科院分区：
文献类型：
--
作者：
Stith,BJ;Maller,JL
胰岛素和黄体酮都能刺激非洲爪蟾（xenopus laevis） 6期大卵母细胞生发囊泡破裂（GVBD）。大量研究表明，孕酮处理的卵母细胞在GVBD之前，细胞内pH （pHi）和核糖体蛋白S6磷酸化增加。本研究比较了胰岛素和黄体酮对pHi和S6磷酸化的影响。两种激素对pHi和S6磷酸化的增加程度相似，且两种激素对pHi变化的时间过程相同。在7 × 10−8 m浓度下观察到胰岛素的半最大效应。在1nm霍乱毒素存在下，黄体酮诱导这两种反应的能力被抑制，而胰岛素的作用不受影响。然而，两种激素诱导的GVBD均被霍乱毒素阻断。在对黄体酮或胰岛素均未发生GVBD的小的IV期卵母细胞中，对黄体酮的反应发生了部分pHi增加，但没有S6磷酸化，但对胰岛素的反应发生了这两种事件。这些结果表明，IV期卵母细胞在激素作用下无法经历GVBD，并非由于无法增加pHi或磷酸化S6。本研究结果还表明，胰岛素和黄体酮对这些事件的调节是不同的。
Both insulin and progesterone are capable of stimulating germinal vesicle breakdown (GVBD) of large, Stage VI oocytes ofXenopus laevis. Numerous studies have shown an increase in intracellular pH (pHi) and ribosomal protein S6 phosphorylation prior to GVBD in oocytes treated with progesterone. In this study the effect of insulin and progesterone on pHi and S6 phosphorylation was compared. Both hormones increased pHi and S6 phosphorylation to similar levels and the time course of pHi change was the same for both hormones. Half-maximal effects of insulin were observed at 7 × 10−8Mconcentrations. In the presence of 1 nMcholera toxin, the ability of progesterone to induce these two responses was inhibited while the action of insulin was unaffected. However, GVBD induced by either hormone was blocked by cholera toxin. In small, Stage IV oocytes that do not undergo GVBD in response to either progesterone or insulin, a partial increase in pHi without S6 phosphorylation occurred in response to progesterone but both events occurred in response to insulin. These results suggest that the inability of Stage IV oocytes to undergo GVBD in response to hormone is not due to a failure to increase pHi or phosphorylate S6. The results in this paper also indicate that these events are regulated differently by insulin and progesterone inXenopusoocytes.