The effect of lead on calcium release activated calcium influx in primary cultures of human osteoblast-like cells.

To further understand the significance of bone as a target tissues of lead toxicity, as well as a reservoir of systemic lead, it is necessary to define the effect of lead on the calcium release activated calcium influx (CRACI) in primary cultures of human osteoblast-like cells (OLC). Pb2+ inhibited the immediate CRACI dose-dependent manner. Influx of Pb2+ into human OLC was increased dose-dependent manner. The present study demonstrates that the interference of Pb2+ with CRACI of human OLC is at least twofold: (1) the initiation of CRACI, i.e., the measurable influx of Ca2+ upon Ca2+ readdition, is partially inhibited by Pb2+ and (2) the influx of Pb2+ was enhanced after CRACI had been induced.