To Investigate The Significance Of HIF-1α,VEGF And PIGF Of The Serum In Healthy Tibetan And Han In Different Altitude

Objective：To measure the level of hypoxia inducible factor-1α（HIF-1α） vascularendothelial growth factor （VEGF）and placenta growth factor （PIGF） of the serum inTibetan, the moved Han and Han in plain. To analyse the difference of them at thedifferent altitude, the correlation among them and the correlation between HIF-1α,HIF-2α with arterial partial pressure of oxygen （PaO₂）.In order to understand theadaptability of Tibetan and Han to high altitude. To investigate the significance ofHIF-1α,VEGF and PIGF in different altitude.Methods：Chooses healthy adult of Han in plain （altitude5m,group1）, in moderatealtitude （2261m, group2）and high altitude （4380m,group4）, healthy adult ofTibetan in moderate altitude （2261m, group3） and high altitude （4380m,group5）.The age of them between of20and30. Each group has20men. Migrants live inplateau more than2years. Tibetan and Han of high altitude were done the chronicmountain sickness scores（CMS）.Their scores were all less than five points. Everysubject signed the informed agreement. All of them measured hemoglobin andarterial blood gas analysis. Extracted venous blood, separated serum and saved in-80℃refrigerator. The level of HIF-1α,VEGF and PIGF were determined withELISA.Compared the difference within groups.Analyzed the correlation amongthese three factors and them with PaO₂.Results：1. The comparison of the Hb and PaO₂among each group （table1）.PaO₂: There was significant difference of PaO₂among the five groups（P <0.01）.ThePaO₂of group1was higher than other groups（P <0.01）. The PaO₂of group4andgroup5were lower than group2and group3（P <0.01）. But PaO₂between group2and group3didn’t have significant difference （P>0.05）.The PaO₂between group4and group5also didn’t have significant difference （P>0.05）.Hb （g/dl）: There was significant difference among the five groups.Hb of group4and group5were higher than other groups（P <0.01）. Hb of group5was lower thangroup4（P <0.01）. Hb among group1, group2and group3didn’t have significantdifference （P>0.05）.2. The comparison of HIF-1α,VEGF and PIGF level among each group （see table2）.HIF-1α: There was significant difference among the five groups. HIF-1α of group4was higher than other groups （P <0.05）.HIF-1α of group5was higher than the thirdgroup （P <0.05）.There was no significant difference among group1, group2andgroup3.（P>0.05）.VEGF:There was significant difference Among5groups.The level of VEGF waslower than group1,2and3（P<0.05）, group5was lower than group1,3and5（P<0.05）.There was no significant difference among group1, group2and group3（P>0.05）, between group2and group5were also no significant difference （P>0.05）;PIGF: There was significant difference among5groups. Group2and3were lowerthan group1（P<0.05）,group4was highest in all group（sP<0.05）. Group5was lowerthan group4（P<0.05），higher than group2and3,no significant difference withgroup1（P>0.05）.3. The correlation of HIF-1α, VEGF and PIGF with PaO2.There were negative correlation between HIF-1α,VEGF and PIGF with PaO2（requals-0.291,-0.686,-0.511respectively,P <0.01）.4. The correlation between PIGF with HIF-1α and VEGF.PIGF positive correlated with HIF-1α and VEGF （r equals0.401,0.440respe-ctively,P <0.01）Conclusions：1.With the rise of altitude, the PaO₂decreased.It is the same level ofPaO2in the same elevation in Han and Tibetan. Hb increases only in high altitude,theHb of Tibetan is significantly lower than Han. That means only when hypoxiadecreased to certain degree, the Hb will increase.Tibetan has better hypoxiaadaptability than Han.2. In high altitude,HIF-1α increased significantly, but there is no significantdifference between Han and Tibetan. It’s tip that HIF-1doesn’t increase until oxygento a certain degree in the same low oxygen levels,HIF-1α is identical. 3.VEGF increased in high altitude, there was significant difference betweenTibetan and Han.That indicated that VEGF is sensitive to hypoxia in Han thanTibetan.4.PIGF decreased in moderate high altitude than plain.PIGF of Han in highaltitude was higher than Tibetan and Han in moderate altitude.PIGF of Tibetan waslower than moderate altitude and Han in high altitude,but there was no significantdifference with plain.That may be indicated that PIGF was depressed by mildhypoxia,it will increase only when hypoxia to a certain degree, Han was higher thanTibetan.5.There were negative correlation between HIF-1α,VEGF and PIGF with PaO₂.PIGF positive correlated with HIF-1α and VEGF.