Hepatic injury in a rat cardiopulmonary bypass model

An increasing number of patients were undergoing cardiac surgery with cardiopulmonary bypass (CPB) and more attention had been paid to hepatic injury after CPB. This study was designed to study how CPB could induce and aggravate the hepatic injury in a rat model. Male Sprague-Dawley rats were randomly divided into two groups (n=12): sham and CPB groups. Blood samples were collected at the beginning, at the cessation of CPB, and at 0.5, 1, 2, 3 and 24 h post-operation. Liver samples were harvested at 24 h after operation. In CPB group, the levels of serum liver enzymes and tumor necrosis factor-alpha, activities of inducible nitric oxide synthase, malondialdehyde and myeloperoxidase in liver tissue were significantly increased. In addition, swollen hepatocytes, vacuolization and congestion in sinusoids were observed. On the contrary, the activities of liver antioxidative enzymes and the concentration of glutathione (GSH) decreased remarkably. All results indicated that CPB would induce and aggravate hepatic injury by facilitating oxidative stress and the systemic inflammatory response.