The Changes Of C-fos And INOS And MPO And The Relationship With The Energy Metabolism In Brain During Liver Ischemia And Reperfusion Injury In Rats

Objection: The changes of c-fos, inducible oxide synthase(iNOS), myeloperoxidase (MPO) and malondialdehyde (MDA) in brain and the realationship among them in liver ischemia-reperfusion( I/R) injury were observed, the relationship with the energy metabolism in brain were investigated and its mechanism were studied following the process of liver I/R in rats. Methods: A model of liver I/R injury was established by imitation. 48 healthy Wistar rats were randomly divided into 6 groups as following(n=8): the control group(CTL,the group of sham operateration), simply ischemia 30min without reperfusion (I group), reperfusion following ischemia 30min(I/R group), 1 hour reperfusion following ischemia 30min(I/Rlh), 2 hours reperfusion following ischemia 30min(I/R2h) and 4 hours reperfusion following ischemia 30min(I/R4h). The expressions of c-fos and iNOS in brain were detected by means of immunohistochemical method in each group. The changes of MPO and MDA in brain were measured.The changes of succinic dehydrogenase (SDH), ATP-ase, lactic dehydrogenase (LDH) and lactic acid(LD) were also measured. Results: During the process of liver I/R, the expressions of c-fos and iNOS in brain were increased significantly in I/R group compared with CTL (P<0.01), the significance was also found:I/Rlh,I/R2h, I/R4h group vs. I and I/R group(P<0.01); I/R2h group vs. I/Rlh group (P<0.01) and I/R4h group compared with I/R2h group (P<0.01). The increase of MPO was obviously staistic significance in I group (P< 0.01); compared with I/R and I/Rlh group, a remarkable elevation was showed in I/R4h (P<0.01), there was no significance between I/R4h group and I/R2h group (P>0.05). The level of MDA was increased in I/R group compared with CTL (P<0.05) and its peak value at I/R2h (P< 0.05). There was a positive correlation between iNOS, MPO, MDA and c-fos (r=0.991, 0.948, 0.964, P<0.01); MPO, MDA and iNOS (r=0.936, 0.958, P<0.01); MPO and MDA (r=0.947,P<0.01). The decrease of SDH activity was significant in I group (P<0.05), so was in I/R2h group compared with I/R group (P<0.05), there was no significant decrease between I/R4h group and I/R2h group (P>0.05). The activity of ATPase in I/R group (Ca2+-ATPase) and I/Rlh group (Na+-K+ATPase) was less than that in CTL (P<0.01), both Na+-K+ATPase and Ca2+-ATPase activities had obvious changes in I/R4h group vs. I/R group (P<0.01), but not in I/R2h group compared with I/R4h group (P>0.05). The activity of LDH and the amount of LD were higher in I group (P<0.05), both had significance in I/Rlh, I/R2h group compared with I group (P< 0.05), the decrease of LD had no significance in I/R4h group compared with CTL (P>0.05). Conclusion: The changes of c-fos, iNOS and MPO in brain may be involved in the pathogenesis of the brain injury and the disorder of energy metablism in brian was obvious after reperfusion induced by liver ischemia.