妊娠期绵羊不同程度高原缺氧模型的建立

Reproduction of the model of plateau hypoxia in different degrees in gestational sheep

目的应用西北人工实验舱建立妊娠期绵羊不同程度高原缺氧模型,并评估其氧合状态及氧化损伤程度。方法采用24只人工授精配种成功的妊娠期绵羊,随机均分为平原对照组(LAC)、轻度低氧暴露组(MHE)和重度低氧暴露组(SHE)。用人工实验舱模拟西北地区高原低氧低压低温环境,通过调节温度、湿度、压力和空气氧含量等参数制备MHE与SHE动物模型,分别于建模前(0d)与建模后7、15、30、90、120d检测3组动物氧合状态、生命体征及行为模式,动态检测肝脏组织氧化损伤标志物的水平。结果经不同条件人工实验舱造模30d(MHE组)及90d(SHE组)后,妊娠期绵羊动脉血气指标分别达到轻度和重度缺氧诊断标准。建模后90d,与LAC组比较,MHE组及SHE组妊娠期绵羊呼吸频率减低(P<0.05),心率升高(P<0.05),运动减少,且SHE组饮食较MHE组减少;建模后120d,MHE组及SHE组妊娠期绵羊蛋白质氧化损伤的生物标志物羰基(CO)和细胞氧化损伤的生物标志物丙二醛(MDA)水平均明显高于LAC组(P<0.05),且SHE组明显高于MHE组(P<0.05)。结论应用西北人工实验舱成功建立了妊娠期绵羊不同程度高原缺氧模型。高原低氧环境可引起妊娠期绵羊氧化应激损伤。

Objective To reproduce the model of plateau hypoxia in different degrees in pregnant sheep by using hypobaric chamber for the evaluation of oxygenation status and oxidative damage in these models. Methods Twenty-four pregnant sheep conceived by successful artificial insemination were randomly divided into three groups（8 each）： low altitude control group（LAC）, mild hypoxia exposure group（MHE） and severe hypoxia exposure group（SHE）. Sheep in the latter two groups were fed in hypobaric chamber, and the models were reproduced by adjusting the temperature, humidity, pressure and oxygen content simulating environment of different altitudes of northwest China. The degree of oxygenation, vital signs, behavior pattern and oxidative damage biomarkers were dynamically determined before modeling and 7, 15, 30, 90, 120 days after modeling, respectively. Results Thirty and 90 days after modeling, the arterial blood gas parameters of sheep in MHE and SHE group met the diagnostic criteria. Ninety days after modeling, the respiratory frequency decreased（P〈0.05）, the heart rate increased（P〈0.05）, and lassitude were found in MHE and SHE groups than in LAC group; the consumption of feeding decreased in SHE group than in MHE group（P〈0.05）. One hundred and twenty days after modeling, the CO and MDA increased significantly in MHE and SHE groups than those in LAC group（P〈0.05）, also in SHE group compared with that in MHE group（P〈0.05）. Conclusion Different degrees of hypoxia models of pregnant sheep have been successfully reproduced by using hypobaric chamber, and the results showed that the hypoxic environment in high altitude regions may cause oxidative stress injury of gestational sheep.