Other molecular processes that are redox-sensitive relate to total protein carbonyl content, an important index of whole cell protein oxidation.33 Accumulation of protein carbonyls has been observed in several human pathologies, including diseases of the lung.34 We found increased protein carbonylation in basal conditions, in PAH-hPASMCs compared with control cells, along with increased carbonyl content in response to serotonin in WT mPASMCs, an effect that was absent in mPASMCs from Nox1−/− mice. Here, NOX1 is linked to pulmonary arterial hypertension.