Nox1 knockdown restores PKCε gene expression. H9c2 cells were transfected with siRNA against Nox1 or Nox4, respectively, for 24 h, followed by treatment with 10 μM norepinephrine (NE) for 48 h. A) PKCε protein, measured by Western blot. B) PKCε mRNA, determined by qRT-PCR. Data are means ± se, n = 6. *P < 0.05 vs. control.