In vitro changes in capacitative Ca2+ entry in neuroblastoma X glioma NG108-15 cells

Changes in capacitative Ca2+ entry were studied in neuroblastoma x glioma NG108-15 cells with fura-2 fluorescence measurements in the following three culture conditions. The application of thapsigargin (250 nM) with a Ca2+-free solution depleted intracellular Ca2+ stores and the capacitative Ca2+ entry was induced by the addition of extracellular Ca2+ in the cells cultured in the medium for proliferation. The capacitative Ca2+ entry decreased in the cells cultured in the medium for neuronal differentiation. When these cells resumed proliferation after changing the culture media to the initial medium for proliferation, the capacitative Ca2+ entry increased again and exceeded the level in the initial proliferation state. These results suggested that the capacitative Ca2+ entry occurred more intensely at the proliferation state than at the neuronally differentiated state.