[Effect of SP on intracellular free calcium concentration in cultured osteoblast].

OBJECTIVE: To investigate the effect of SP on intracellular free calcium concentration (Ca2+)i in cultured osteoblast. METHODS: Effect of SP on intracellular free calcium was measured using cell culturing and laser scanning confocal microscopy with fluo-3/AM as a fluorescence probe. RESULTS: After treated with SP(10(-4) mol/L), 70% of the cells responded to it; the intracellular (Ca2+)i increased markedly [fluorescence intensity increased by (90 +/- 18)%]. CONCLUSIONS: These results suggested that calcium may have a role as a intracellular secondary messenger in the action of SP in osteoblast.