To Investigate The Changes And Significance Of HIF-1α And HIF-2α Of The Serum In Healthy Native Tibetan And Immigrant Han In Different Altitudes

Objective: To investigate the significance of hypoxic inducible factor （HIF）-1αand HIF-2α in Han in plain、native Tibetan and immigrant Han in different altitudes.Methods: Chose healthy adult of Han in plain （altitude5m）, native Tibetan andimmigrant Han in moderate （2261m）and high altitude （4380m）.The serum concentrationof HIF-1α and HIF-2α was measured with enzyme linked immunosorbent assay（ELISA）.Analyzed the correlation between HIF-1α and HIF-2α, them with arterial partialpressure of oxygen（PaO2）and hemoglobin（Hb）.Results: The level of HIF-1α increased in both Tibetan and Han in high altitude（P<0.01）. But there was no significant difference between Tibetan and Han （5.27±0.98,6.06±1.85,P<0.01）.The level of HIF-2α in Han in high altitude was the highestin all groups. There was no significant difference between Tibetan in moderate andhigh altitude （0.14±0.06,0.18±0.16, P>0.05）. The level of HIF-2α of Tibetan wasless than Han in plain and high altitude. The level of HIF-1α and HIF-2α negativecorrelated with PaO₂（r=-0.475,r=-0.551, all P<0.01）, positive correlated with Hbin Han groups （r=0.433, r=-0.463, all P <0.01）. The level of HIF-1α and HIF-2α didn’t have correlation with PaO2in Tibetan groups（r=-0.270, r=-0.198, allP>0.05）. There was no correlation between HIF-1α and Hb in Tibetan groups（r=－0.141, P>0.05）.There was positive correlation between HIF-2αand Hb in Tibetan groups（r=0.325,P <0.01）. There was positive correlation between HIF-1α and HIF-2α in Han groups（r=0.505，P<0.01）；There was no correlation between HIF-1α andHIF-2α in Tibetan groups（r=-0.011，P>0.05）.Conclusions:1. HIF-1didn’t increase until oxygen to a certain degree.In the samelow oxygen levels,HIF-1α is identical in Tibetan and Han in same altitude.2.HIF-2α of Tibetan was obviously lower than Han in the same altitude.HIF-2αclosely related with Hb, may play a more important role than HIF-1α in theregulation of Hb. 3.HIF-1α and HIF-2α were all play the role in hypoxia adaption in Tibetan andHan, but they also had difference.HIF-2α may be associated with lower Hb of Tibetan.