Résumé
ve To assess the protective effect of L-arginine on vascular endothelial cell during cardiopulmonary bypass(CPB). Methods 12 adult healthy mongrel dogs of either sex weighing 10-15kg, were divided into L-arginine group (group L, n=6) and control group (group C, n=6) . Femoral artery and vein were cannulated for monitoring of MAP and CVP. Right internal jugular vein was cannulated with Swan-Ganz catheter for hemodynamic monitoring. L-arginine 100 mg?kg-1 was administered intravenously before CPB followed by continuous intravenous infusion at 10mg?kg-1.min-1 to the end of CPB in group L. Control group was treated as group L except the administration of L-arginine. Venous blood samples were taken before CPB, 5min after CPB was started, 15, 45min after aortic cross-clamping and 15, 30min after release of aortic cross-clamp for determination of the plasma levels of metabolites of nitric oxide (NO2- and NO3-), malondialdehyde (MDA) and von Willebrand Factor(vWF). Hemodynamic parameters were measured before CPB, 15 and 30min after release of aortic clamp. Specimens of tissue from femoral artery and descending aorta were taken for microscopic examination at 15,45 min after aortic cross-clamping and 30min after release of aortic cross-clamp.Results There was little difference in plasma NO2- and NO3-concentrations before CPB between the two groups. NO2- and NO3- levels increased significantly after CPB in both groups but were significantly higher in group L than those in group C (P