中文摘要：

目的：探讨δ-氨基γ-酮戊酸合成酶2（ALAS2）基因复合重复多态性与高住高训低练（HiHiLo）训练后左心室结构功能的关联性。方法：选取72名中国北方汉族男性健康受试者进行4周高住高练低训（Hi-HiLo）,方案为每日在低氧环境（O2浓度为14.5%~14.8%,相当于海拔3000 m）中休息10 h,每周进行3次低氧下（O2浓度为15.4%,相当于海拔2500 m）75%.VO2max强度蹬功率自行车训练,其余时间在常氧下训练;测定受试者HiHiLo前后不同状态下左心室结构功能等指标。使用GeneScan和测序方法分析该基因多态性的分布特征,并进行该多态与HiHiLo训练敏感性的关联性分析。结果：HiHiLo后,≤166bp组在安静及不同运动负荷下每博输出量的增加幅度（△b-SV、△b-SVI、△100W-SV、△100W-SVI）显著性低于〉166 bp组（P〈0.05）;≤166 bp组在安静及不同运动负荷下心输出量的下降幅度（△b-CO、△50W-CO、△100W-CO、△150W-CO、△b-COI、△50W-COI、△150W-COI）、射血分数的下降幅度（△100W-EF）、心率的下降幅度（b-△HR、50W-△HR、100W-△HR、150W-△HR）均显著性高于〉166bp组（P〈0.05）。结论：ALAS2基因复合重复多态中≤166bp基因型在心脏功能指标中HiHiLo训练敏感性最高,可作为预测HiHiLo训练后左心室功能变化的分子遗传学标记。

英文摘要：

Objective： To investigate the association between the compound dinucleotide repeat polymorphism in intron 7 of ALAS2 gene and left ventricular structure and function during HiHiLo in men of Han nationality in Northern China.Methods： 72 healthy young men of Han nationality in Northern China were selected to undergo 4 weeks HiHiLo program（hypoxic exposure 10 hours everyday with14.5%～14.8% O2,3 times hypoxic training every week with 15.4% O2 which equals to 2 500m above the sea level and high-intensity ergometry cycling with 75%V·O2max,and the other time conduct normal training at sea level.The left ventricular structure and function parameters under different loads were measured before and after protocol.GeneScan and gene sequencing was used to analyze the distribution of the FECH polymorphism.The association of the polymorphism with HiHiLo response was analyzed.Results： After HiHiLo,the increased changing rate of stroke volume under different loads（△b-SV、△b-SVI、△100W-SV、△100W-SVI）in ≤166bp genetype was significantly lower than in 166bp genetype（P0.05）;The decreased changing rate of cardic output,ejection fraction and heart rate under different loads（△b-CO,△50W-CO,△100W-CO,△150W-CO,△b-COI,△50W-COI, △150W-COI,△100W-EF,b-△HR,50W-△HR,100W-△HR,150W-△HR）in ≤166bp genetype were significantly higher than in 166bp genetype（P0.05）.Conclusion：The≤166bp genetype of compound dinucleotide repeat polymorphism in intron 7 of ALAS2 gene has association with higher left ventricular function response in HiHiLo and could be the genetic marker in predicting HiHiLo response.