Fig. 8. Episodic hypoxia induces antioxidant mechanisms and attenuates ROS production. (A) Microarray analysis of expression level changes of genes associated with antioxidant defense in CsA treated mice (upper panel, n=5 each) and in mice with induced tubular-specific VHL-KO (lower panel; data taken from GSE44925) [21]. *: p<0.05, **: p<0.01, ***: p<0.001. Error bars indicate standard deviation. (B) Cellular ROS production in DCT cells after exposure to different types of hypoxia followed by 1 h re-oxygenation was monitored by 2', 7'-dichlorofluorescein diacetate (DCFDA) assay. Significance to normoxia ##: p<0.01, ###: p<0.001. Asterisks denote significance between hypoxic groups. ***: p<0.001. Error bars indicate standard deviation of three independent biological experiments, each with 10 replicates.