慢性缺氧幼鼠模型的建立

目的 建立一种适合紫绀型先天性心脏病研究的慢性缺氧幼鼠模型。方法 健康雄性5周龄SD大鼠20只，随机均分2组。对照组和低氧组大鼠分别饲养在常压常氧下和常压低氧箱内（吸入氧浓度分别为21％和10％），饲养2周后检测动脉血气、红细胞计数、心脏质量／体质量比值以及心肌和肺组织抗氧化酶活性的变化。饲养期间每2天记录水和食物的消耗量。结果 与对照组比较，低氧组大鼠红细胞比容、血红蛋白含量和红细胞计数均明显增加（P〈0．01），进食量及饮水量均明显减少，体质量也明显降低，而心脏质量及心脏质量／体质量比值明显增加（P〈0．01）。低氧组心肌及肺组织谷胱苷肽过氧化物酶（GSH—PX）活力、超氧化物歧化酶（SOD）活性、总抗氧化能力（T—AOC）均明显降低（P〈0．01）。结论 建立的慢性缺氧幼年大鼠模型符合临床紫绀型先天性心脏病的病理生理特点，可以用于紫绀型先天性心脏病器官损伤的研究。

Construction of the Chronic Hypoxia Model in Immature Rats

Objective To contrust the model of chronic hypoxia in rats for cyanotic congenital heart defects.Methods Male Sprague-Dawley rats(5-weeks old) were randomly divided into 2 groups (n=10 per group): in control group,control normoxic animals exposed to room air [fraction of inspired oxygen(FiO_2),0.21%];in hypoxia group,chronic hypoxic animals(FiO_2,0.10%) were housed in the normobaric hypoxic chambers described below for 2 weeks.Water and food consumption was assessed every 2 days.Aterial blood gas analysis,antioxidase activitity,red blood cell counts and the heart weight/body weight ratio were observed at the end of the 2-week exposure to normoxic or hypoxic environment.Results In hypoxia group there was a significant decrease in hematocrit values,hemoglobin concentrations,and red cells as compared with control group(all P<0.01).In hypoxia group,the amount of ingested food and the amount of ingested water were less than those in control group,and body weight was lower in hypoxia group than that in control group(P<0.01).In hypoxia group,heart weight and the heart weight/body weight ratio were higher,and antioxidase activitities were lower(P<0.01) than those in control group.Conclusion The estabilished model was in conformity with pathophysiological characterics and pathological changes of chronic hypoxia heart disease clinically.It allows experiments to be performed to study the cyanotic myocardium.