总之，HIF?1α在脑缺氧缺血性损伤中的保护机制研究尚未深入，很多方面仍未得到直接证据，而目前还存在争议。如Cramer等[29]在体外试验中发现在HIF?1α基因缺失的髓细胞，无论在缺氧环境还是正常氧浓度下，其ATP和乳酸的含量均明显降低，而乳酸含量是髓细胞活化发挥炎症作用的标志之一，提示HIF?1α可能会促进炎症反应的发生。另外，Helton等[30]通过敲除大鼠大脑HIF?1α基因发现，非但未增加缺氧缺血损伤，反而减轻了缺氧缺血后脑损伤。关于HIF?1α具体的脑保护作用机制仍有待进一步的研究和探讨。
4 问题与展望
HIF?1α对脑缺氧缺血性损伤的保护作用是多方面的，随着对HIF?1α及其下游缺氧反应基因研究的深入，其在脑缺氧缺血损伤中的作用会更加明确。HIF?1α有可能成为脑保护治疗中最有前途的靶基因，具有广阔的应用前景，它为临床治疗脑缺氧缺血性损伤提供了一种新的治疗策略。【参考文献】
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