The effects of CO are dependent on the intracellular GSH level.

A. ECs were pretreated with 0.5-glutathionylated STAT3 was then detected as described in Figure 5. *P<0.05 compared with untreated ECs. ^#P<0.05 compared with TCDC or MC alone. B. ECs subjected to IL-6 treatment for 10 min were pretreated with 0.5 mM BSO for 30 min and then cultured without further treatment or exposed to TCDC or MC for 12 hours. Cell lysates were then subjected to western blotting.