Changes and significance of serum nitric oxide levels in the early stage after rat liver transplantation

Objective To investigate the changes and significance of serum nitric oxide levels in the early stage after rat liver transplantation.Methods Male Sprague Dawley rats were used as do- nors and recipients of orthotopic liver transplantation,and the time of cold preservation and anhepatic phase was 4 h and 25 min respectively.Forty-eight rats were randomly divided into groups A,B and C (n=16 each).The samples of blood were taken from vena cava and hepatic tissues from left lobe 2 h, 4 h,6 h in groups A,B and C respectively after liver graft reperfusion.ALT and NO levels in serum were detected,and the expression of NF-κB in hepatic tissue was examined by immunohistochemical technique.Amounts of bile flow in 5 min after liver graft reperfused initially were measured.The pathological changes in liver tissues were observed.Results Amounts of bile flow in 5 min in group A (3.73±1.11μl) were greater than those group B (2.35±0.92μl) and group C (2.23±0.81μl) (P0.05).Serum ALT levels in group A (468±36 IU/L) were lower than those in group B (619±49 IU/L) and group C (820±65 IU/L) (P0.05),and serum ALT levels in group B were lower than those in group C (P0.05).Serum NO levels in group A (14.2±1.5μmol/L) were higher than those in group B (10.5±1.2μmol/L) and group C (10.3±1.1μmol/L) (P0.05).Percentage of positive cells expressing NF-κB p65 from hepatic tissues in group A (23.5%±1.9%) was lower than that in group B (43.8%±3.8%) and group C (48.6%±5.1%)(P0.05).Histopathologic examination showed that the injuries in hepatic tissues were aggravated as reperfusion time prolonged, meanwhile,Pearson correlation analysis revealed that the levels of NO were negatively correlated with NF-κB p65 and ALT closely (r:-0.77,-0.74 respectively,P0.01).Conclusion In the early stage after rat liver transplantation,serum NO levels were decreased and the activities of NF-κB enhanced,which resulted in the farther damage of liver function and hepatic tissue structures as reper- fusion time prolonged.