The mechanism of extracellular ATP regulating intracellular Ca~(2+)

By using micro-fluorometric measurement of intracellular free Ca~(2+) concentration,this paper studies regulative effects of extracelluar ATP on intracellular Ca~(2+) concentration in rat β cells and INS-1 cells.Our results demonstrate that ATP has different regulative effects on Ca~(2+) in rat β cells and INS-1 cells.It suggestes that extracellular ATP elevated intracellular Ca~(2+) by mobilization of calcium store in rat pancreatic β cells.In contrast,extracellular ATP elevates intracellular Ca~(2+) via influx of extracellular Ca~(2+) in INS-1 cells.