Effect of Pb on barrier permeability of the in vitro BBB model. We used C6 cells and ECV304 cells to establish the in vitro BBB model. (A) Values of transendothelial electrical resistance (TEER) and (B) Flux of FTIC-dextran were assessed in response to control group (Con), ECV304+Pb group and C6+Pb group at different time points. Con group, in which the in vitro BBB model was established without any stimulation; C6+Pb group, in which Pb was added into the culture plates and C6 cells were stimulated by Pb; ECV304+Pb group, in which Pb was added into the inner chamber and ECV304 cells were stimulated by Pb. Data represent as means ± SD (n=3), *p < 0.05 vs. Con.