Effects Of Ginkgo Biloba Extract On The Expression Of NF - κB P65 In Hepatic Ischemia - Reperfusion Injury

Objective: To investigate the protective effect of Ginkgo biloba extract (EGb) on theexpression of NF-κB p65against hepatic ischemia/reperfusion injury in rats. Try toevaluate the mechanism of the hepatic ischemia/reperfusion injury in rats.Methods:45healthy male SD rats were randomly divided into5groups:(1)shamgroup;(2) model group (I/R group);(3)low dosing (20mg/kg) group;(4)normal dosing(40mg/kg) group;(5) high dosing (60mg/kg) group. Sham group were only subjectedto anesthesia and laparotomy. All rats except sham group were dissociated andclamped the hepatoduodenal ligaments with microvascular clamps after carried outlaparotomy in order to achieve ischemia. After30miniutes ischemia, the clamps wereopened and reperfusion was allowed for60minutes. Blood and lever tissues sampleswere obtained at the end of I/R:(1) determine the levels of serum alanineaminotransferase(ALT) and aspartate transaminase(AST);(2)determine the maleicdialdehyde(MDA) levels and superoxide dismutase(SOD) activity in livertissue;(3)observe the microscopical structure of the liver tissue by HEstaining;(4)determine the expression of NF-κB p65by methods of western blot.Results:(1)The levels of serum ALT and AST in model group were obviouslyelevated, and significantly different from those in sham group(P<0.01). In treatmentgroup, the levels of serum ALT and AST significantly decreased compared withmodel group, except in the low dosing group(P<0.01).(2)After I/R,MDA levels inliver tissue increased significantly, whereas, SOD activity descended obviously, therewere significant difference between model group and sham group(P<0.01);Intreatment group, MDA levels decreased and SOD activity was stepped up, whichshowed significant difference compared with model group, except no difference inlow dosing group(P<0.05,P<0.01).(3)Model group and EGb group had liver antralbecoming bloodshot and distention of liver cells to different degree, and the injurydegree of liver tissue in EGb group was significantly lightened. But there was notsignificantly changed in liver tissue of low dosing group compared with model group.(4) In the model group, the expressions of NF-κB p65in liver tissues whichdetected by western blot were significantly higher than in sham group, whereas, thenormal and high dosing group were significantly decreased compared with it(P<0.01).Conclusion: The mechanism of EGb protection from ischemia reperfusion injury ofliver in rats may be associated with anti-oxygen-derived free radicals and inhibitingthe expressions of NF-κB p65.