Fig. 6.

Effects of bafilomycin A1 treatment on Ag dissolution and metallothionein expression following exposure to AgNPs. A549 cells were incubated in culture medium with or without 200 nM BFA1 for 24 h before treating with AgNPs (50 μg Ag/ml) for an additional 24 h. a Ag concentrations in the soluble (left) and insoluble fractions (right). Values (ng/10⁴ cells) are mean ± standard deviation (n = 3). b mRNA levels of MT-I (left) and MT-II (right). Total RNA was isolated and subjected to real-time PCR analysis using MT-I or MT-II gene-specific primers. Each value (mean ± standard deviation, n = 3) was normalized to the GAPDH level, and the control value (cells without BFA1 and AgNPs) was set to 1. **P < 0.01 compared to cells without BFA1 and with AgNPs