PAS-Na treatment mitigated the Pb-induced increase in intracellular Ca2+ in primary hippocampal neurons. a Primary hippocampal neurons were treated with increased concentrations of PbAc for 24 h. b Primary hippocampal neurons were treated with 50 μM PbAc for 24 h, followed by 100, 200 or 400 μM PAS-Na treatment for 24 h. a, b Representative fluorescent images of intracellular Ca2+ and quantifications of corresponding fluorescence intensity. Scale bar = 20 μm. * P < 0.05 and * * P < 0.01, compared to the control group. ##P < 0.05 and ##P < 0.01, compared to the Pb-treated group.