Dopaminergic cells express subunits of the NADPH oxidase complex. (A) mRNA from untreated N27 cells was reverse transcribed and amplified using PCR primers specific to rat NADPH oxidase subunits. Nox1-4 subunits as well as p22phox, p40phox, p47phox, and p67phox were identified by their mRNA expression. Nox2, p22phox, and p47phox were also detected by their protein expression (Western immunoblot, B-D) and cellular localization (immunofluorescence, B-D). Scale bar equals 10 μm; all three micrographs were taken at the same magnification.