['Acute lung injury is a common complication after cardiopulmonary bypass (CPB). Oxidative damage greatly impacts CPB-induced lung ischemic pathogenesis and may represent a target for treatment. We aimed to investigate whether curcumin upregulates heme oxygenase 1 (HO-1) expression and ameliorates lung injury in a rat CPB model.', 'A total of 80 male Sprague-Dawley rats were divided into 2 sets of 5 groups (n = 8 per group): sham; control (CPB); vehicle; low-dose curcumin (L-Cur); and high-dose curcumin (H-Cur). Animals were pretreated with a single intraperitoneal injection of vehicle, L-Cur (50 mg/kg), or H-Cur (200 mg/kg) 2 hours prior to CPB. Lung tissue, serum, and bronchoalveolar lavage fluid was harvested 2 or 24 hours postoperatively. In the control group, CPB-induced lung injury was confirmed by histopathologic examination and a significantly increased wet-to-dry lung weight ratio and pulmonary permeability index value was observed (P < .05 vs sham group). Cardiopulmonary bypass was associated with a marked rise in the level of malondialdehyde and myeloperoxidase and a fall in superoxide dismutase 2 and 24 hours after surgery (P < .05 vs sham group). Administration of curcumin ameliorated lung damage and reversed the oxidative stress markers in a partially dose-dependent manner (P < .05 vs vehicle group). Furthermore, HO-1 gene transcription and protein expression were elevated to a greater extent in the lungs after curcumin pretreatment compared with the vehicle pretreatment.'] Does curcumin attenuate cardiopulmonary bypass-induced lung oxidative damage in rats?