Leoni S, Spagnuolo S, Terenzi F, Marino M, Bolaffi C, Pulcinelli F M, Mangiantini M T
Dept. of Cellular and Developmental Biology, University of Rome La Sapienza, Rome, Italy.
Biosci Rep. 1993 Feb;13(1):53-60. doi: 10.1007/BF01138178.
The changes in intracellular calcium concentration and IP3 production after the addition of epinephrine were analysed in adult, fetal (20th-22nd day of intrauterine life), and regenerating rat hepatocytes (4 h-24 h after partial hepatectomy) to determine whether the signal transduction is the same in quiescent proliferating and differentiating cells. The epinephrine treatment causes a significative cytosolic calcium transient in hepatocytes isolated in the last day of fetal life (22-day old) and in the early stage of regeneration (4 h). This effect is not significant in the previous stage of fetal life (20-day old) and at the onset of M phase of cell cycle after partial hepatectomy (24 h). [3H]myo inositol incorporation into IP3 and IP4 is higher in 20 day fetal and regenerating hepatocytes with respect to the control. In these cells the epinephrine does not affect basal level of IP3 and IP4, while it causes a substantial increase of these inositol phosphates in adult hepatocytes. [3H]myo inositol incorporation into PIP2 is very low at the 20th day of fetal life. Epinephrine has no effect on this parameter in fetal and regenerating hepatocytes. Our results show that the epinephrine signal is mediated differently in proliferating and in quiescent hepatocytes.
分析了成年、胎儿（子宫内生活第20 - 22天）和再生大鼠肝细胞（部分肝切除术后4小时 - 24小时）在添加肾上腺素后细胞内钙浓度和IP3生成的变化，以确定在静止、增殖和分化细胞中信号转导是否相同。肾上腺素处理在胎儿期最后一天（22日龄）分离的肝细胞和再生早期（4小时）引起显著的胞质钙瞬变。在胎儿期的前一阶段（20日龄）和部分肝切除术后细胞周期M期开始时（24小时），这种作用不显著。与对照组相比，20日龄胎儿和再生肝细胞中[3H]肌醇掺入IP3和IP4的量更高。在这些细胞中，肾上腺素不影响IP3和IP4的基础水平，而在成年肝细胞中它会导致这些肌醇磷酸酯大量增加。在胎儿期第20天，[3H]肌醇掺入PIP2的量非常低。肾上腺素对胎儿和再生肝细胞中的这个参数没有影响。我们的结果表明，肾上腺素信号在增殖和静止的肝细胞中通过不同方式介导。
