Barger S W, Van Eldik L J
Department of Cell Biology, Vanderbilt University, Nashville, Tennessee 37232.
J Biol Chem. 1992 May 15;267(14):9689-94.
The glial-derived protein S100 beta can act as a mitogen or a neurotrophic factor, stimulating proliferation of glial cells or differentiation of immature neurons. We report here that dimeric S100 beta evokes increases in intracellular free calcium concentrations ([Ca2+]i) in both glial cells and neuronal cells. The [Ca2+]i increase exhibited a rapid transient component which was not affected by removal of extracellular calcium and a sustained component which appeared to require influx of extracellular calcium through Ni(2+)-sensitive channels. S100 beta also stimulated hydrolysis of phosphoinositides, suggesting a mobilization of calcium from intracellular stores. These data suggest that although the final biological responses of neuronal and glial cells to S100 beta are different, transduction of the S100 beta signal in both cell types involves changes in [Ca2+]i.
神经胶质源性蛋白S100β可作为一种促有丝分裂原或神经营养因子，刺激神经胶质细胞增殖或未成熟神经元分化。我们在此报告，二聚体S100β可引起神经胶质细胞和神经元细胞内游离钙浓度（[Ca2+]i）升高。[Ca2+]i升高表现出一个快速瞬态成分，该成分不受细胞外钙去除的影响，以及一个持续成分，该成分似乎需要细胞外钙通过镍（2+）敏感通道流入。S100β还刺激了磷酸肌醇的水解，表明钙从细胞内储存库中动员出来。这些数据表明，尽管神经元细胞和神经胶质细胞对S100β的最终生物学反应不同，但两种细胞类型中S100β信号的转导都涉及[Ca2+]i的变化。
