NOS2 and metabolic syndrome: To determine the role of L-arginine on oxidative stress in MetS and OHD MetS with or without OHD-induced detrusor overactivity, the expressions of NOS (iNOS, eNOS, and nNOS), transcription factors (HIF-1α, NRF2, and NFκB), and oxidative stress markers (DNP and nitrotyrosine) were measured by Western Blots (Figure 8).