Renal NOX4 mRNA expression after hypoxia. Gel Star–stained 2% agarose gels demonstrating NOX4 transcripts coamplified with 18S rRNA to control for RNA loading and efficiency of RT-PCR (top panel). Bottom panel shows quantitative NOX4 gene expression after normalization to 18S rRNA. Densitometry values are mean ± SEM (n = 6 mice per group; *P < .05).