Effect Of Cystamine On HIF-1α,Survivin Following Global Cerebral Ischemia In Rats

ObjectiveTo observe the expression of Hif-1αand survivin, and the effects of CYS on them, following the global cerebral ischemia in rats. To explore the neuro-protection mechanisms of CYS.MethodsThe experimental GI model was established by 4-vessel-occlusion method, and confirmed by electroencephalogram (EEG).78 adult male Sprague- Dawley rats were randomly divided into sham group (n=6), global cerebral ischemia group(GI, n=36) and global cerebral ischemia+CYS treatment group (GI+EPO, n=36).CYS were administered to rats in GI+CYS group by abdominal-cavity injections (150mg/kg/day) one time a day. In the sham group, it's only 10ml NS a day for 3 days.In the sham group, hippocampuses were obtained 3 days later. In the GI and GI+CYS groups, hippocampuses were got separately after 6 hours,12 hours,1 day,3 days,5 days and 7 days. The expression of Hif-1 a and survivin were detected by western-blotting.All the data was measured by SPSS16.0. A value of P<0.05 was considered statistically significant. ResultsExpression of Hif-1αIn GI group,the expression of HIF-1αincreases on 12h, and got to the top on the 3d.After 3d, it becomes lower and lower. Compare with the sham group, the expression of HIF-1 a are higher (p<0.05) from 12h to the 7day.In GI+CYS group, the trend is almost the same.But levels of HIF-1 a are lower(p<0.05) compare with the GI group.Expression of survivinIn the GI group, the expression of surviving increases from 12h, and got to the top after 5 days. Compare with the sham group, the levels of survivin from 12 hours to 7 days are higher than the sham group (p<0.05).In the GI+CYS group, it starts to rise on 6h, and gots to the top on the 3 day.The levels of survivin on 6h,12h,1d,3d are higher than the GI group(p<0.05).Conclusion(1) Hif-1αand survivin are over-expressed after severe global ischemia.(2) CYS can depress the expression of Hif-1α, advance the peak time of survivin and increase it's expression level.(3) Expression of survivin may be restrained by Hif-1α,which is over-expressed after severe global ischemia.(4) CYS can increase the expression of survivin by depressing the expression of HIF-1α, which maybe one of the mechanisms how it protect the brain...