Synergistic effects of oPL and insulin on glycogen metabolism in fetal rat hepatocytes.
Synergistic effects of oPL and insulin on glycogen metabolism in fetal rat hepatocytes.
复制标题
oPL 和胰岛素对胎鼠肝细胞糖原代谢的协同作用。
DOI：
10.1152/ajpendo.1984.247.6.e714
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Handwerger,S
中科院分区：
文献类型：
--
作者：
Freemark,M;Handwerger,S
用培养的孕20天胎鼠肝细胞研究了羊胎盘催乳素（oPL）和胰岛素在胎肝糖原代谢调节中的相互作用。oPL（0.75-22.5 μ g/ml）和胰岛素（0.01-1 μ M）均刺激[14 C]葡萄糖掺入糖原的剂量依赖性增加。然而，两种激素的量效曲线并不平行，oPL的最大效应是胰岛素的3.4倍（P <0.001）。这两种激素在低浓度下对[14 C]葡萄糖掺入有协同效应，在最大浓度下有累加效应。绵羊生长激素（oGH）也刺激[14 C]葡萄糖掺入糖原，但效力仅为oPL的12.3%。放线菌酮（20 μ M）消除了胰岛素（1 μ M）、oPL（5 μ g/ml）和oGH（100 μ g/ml）对[14 C]葡萄糖掺入的刺激。虽然oPL和胰岛素的糖原生成作用可能依赖于新的蛋白质合成，但这些研究的结果表明，这些激素通过不同的机制刺激胎肝中的糖原合成。由于胰岛素可增强oPL的糖原生成作用，因此这些激素可能协同作用，促进胎儿的肝糖原储存。
The interactions between ovine placental lactogen (oPL) and insulin in the regulation of fetal liver glycogen metabolism have been studied in cultured hepatocytes from fetal rats on day 20 of gestation. Both oPL (0.75–22.5 micrograms/ml) and insulin (0.01–1 microM) stimulated dose-dependent increases in [14C]glucose incorporation into glycogen. However, the dose-response curves for the two hormones were not parallel and the maximum effect of oPL was 3.4 times greater than that of insulin (P less than 0.001). The two hormones had synergistic effects on [14C]glucose incorporation at low concentrations and additive effects at maximum concentrations. Ovine growth hormone (oGH) also stimulated [14C]glucose incorporation into glycogen but with a potency only 12.3% that of oPL. Cycloheximide (20 microM) abolished the stimulation of [14C]glucose incorporation by insulin (1 microM), oPL (5 micrograms/ml), and oGH (100 micrograms/ml). Although the glycogenic actions of oPL and insulin may depend on new protein synthesis, the results of these studies suggest that these hormones stimulate glycogen synthesis in fetal liver by different mechanisms. Because the glycogenic actions of oPL are potentiated by insulin, these hormones may act in concert to promote hepatic glycogen storage in the fetus.