The effect of lead on intracellular Ca2+ in mouse lymphocytes

Abstract: Objective: Lead exposure is one of major public health problems. The aim of this study was to examine in vitro the effect of lead on lymphocyte intracellular Ca2+ ([Ca2+]i). Methods: Lymphocytes were separated from mice spleen and treated with three doses of PbCl2 (1, 10 and 100μmol/L). [Ca2+]i was measured in a Thermo Labsystems Fluoroskan Ascent after loading the cells with Fura2-AM probe. Results: The lymphocyte [Ca2+]i in 10 and 100μmol/L PbCl2 groups increased to the highest level after 10min of lead exposure (P <0.05). After 1h of lead exposure, however, lymphocyte [Ca2+]i levels were not statistically different from that in control group cells (P >0.05). Removal of Ca2+ from external solution did not significantly affect the PbCl2-induced lymphocyte [Ca2+]i. PbCl2 increased the [Ca2+]i under both normal Ca2+ and Ca2+-free conditions. With pretreatment of calmodulin (CaM) antagonist W7, lymphocyte [Ca2+]i levels were still high, but [Ca2+]i levels were not as high as those in the absence of W7. Conclusion: When the lymphocytes were exposed to PbCl2 ranging from 1 to 100μmol/L, the lymphocyte [Ca2+]i level was increased, but the increase appeared reversible. CaM may play a role in the process of the effect of lead on the lymphocyte [Ca2+]i. [Copyright &y& Elsevier]