RESUMO
Hypoxia inducible factor 1 (HIF-1), a nuclear protein with transcription activity, can make the body produce adaptive response to hypoxia/ischemia by binding to target gene, transcription and post-transcriptional control. Ischemic tolerance refers to the adaptive response to transient ischemia and reperfusion, which can improve tissue tolerance during the following damage caused by more severe ischemic events. The recent studies have found that the expression of HIF-1 has an important significance in ischemic tolerance. HIF-1 may be a key factor of the oxygen signal transduction pathway in the development of cerebral ischemic tolerance.
RESUMO
Objective To research the expression and correlation between erythropoietin(EPO)mRNA and hypoxia inducible factor-1?(HIF-1?)mRNA in rats with brain ischemic tolerance induced by ischemic preconditioning.Methods Models of cerebral ischemic preconditioning and ischemic-reperfusion(preconditioning group)were made by twice suture method,after the short ischemic preconditioning 1 d,3 d,7 d,14 d and 21 d respectively,the models were underwent ischemic-reperfusion again.The infarct volume was measured by tetrazolium chloride(TTC)staining,the expressions of HIF-1? mRNA and EPO mRNA in the different time(1～21 d)of ischemic-reperfusion were detected by reverse transcriptase polymerase chain reaction(RT-PCR)and compared with non-preconditioning group.Results The infarct volume in the 1 d,3 d and 7 d subgroups of preconditioning group were significantly smaller compared with non-preconditioning group(all P