中文摘要：

目的探讨不同程度失血大鼠心肌细胞中缺氧诱导因子-1α（hypoxia-inducible factor—1α，HIF-1α）蛋白和mRNA的表达及意义。方法选用清洁级SD大鼠，建立不同程度的失血模型，随机分为假手术对照组（CON）、失血10％（10-BL）组、失血20％（20-BL）组和失血30％（30-BL）组，利用Powerlab八道生理记录仪监测心功能指标，采用RT—PCR检测HIF—1α mRNA在失血后30min、1h大鼠心肌组织中的表达情况，并用免疫组化染色检测HIF—1α在心肌细胞中的分布。结果不同程度失血后，心功能均降低，1h比30min降低明显（P〈0．05）；RT—PCR半定量结果显示，与CON组相比，10-BL、20-BL、30-BL组HIF—1αmRNA表达逐渐增高（P〈0．05）；免疫组化结果表明，HIF—1α主要分布在心肌细胞细胞质中，在细胞核内也有分布。结论随失血程度增加，时间延长，HIF—1α表达增加，HIF-1α可能参与失血导致的低氧状态下心肌代谢的适应性调节。

英文摘要：

Objective This study was to investigate the protein and mRNA expression of hypoxia inducible factor - 1 α （ HIF - 1 α） in rat with different blood loss. Methods SD rats were used to build the animal model of different blood loss. The rats were randomly divided into normal control group, 10 -BL group,20 - BL group and 30 - BL group. Powerlab muhichannel electrophysiolograph was applied to detect the parameter of heart function. Immunohistochemistry, RT - PCR were used to investigate the expression of HIF -1α at 30 min and 1 h after blood loss, respectively. Results Heart function gradually degrade with the level of blood loss , 1 h was lower than 30 rain （ P 〈 0. 05 ）. The expression of HIF - 1α could not be detected in the control group. The expression of HIF - 1α mRNA in blood loss group was higher than in control group and gradually increased from 10 -BL, reaching its maximum level on 30 - BL（ P 〈 0.05 ）. Immunohistochemistry showed that HIF - 1 α protein was mainly present in cytoplasm and/oreytoblast of cardiac muscle. Conclusion These results suggested that the expression of HIF- 1α increased gradually followed by blood loss level and time prolong. HIF- 1α expression may play a key role in the process of myocardial metabolism in hypoxia caused by blood loss in mice.