间断性头高位对模拟失重兔动脉内皮素表达和组织形态的影响  

Effects of Intermittent Head-up Tilt on the Endothelin Expression and Morphological Changes of Artery during Simulated Weightlessness in Rabbits.

作　　者：孙喜庆[1] 王冰[1] 孙会品[1] 石菲[1] 耿捷[1] 王永春[1] 

机构地区：[1]第四军医大学航空航天生物动力学教研室,陕西西安710032

出　　处：《航天医学与医学工程》2006年第4期265-268,共4页Space Medicine & Medical Engineering

基　　金：国家自然科学基金资助项目(30000197)

摘　　要：目的观察21d模拟失重期间间断性头高位45°对兔股动脉及颈动脉内皮素(ET-1)表达和组织形态的影响。方法24只健康雄性兔,随机分为对照组、模拟失重组和对抗组,每组8只。模拟失重组兔在21d实验期间保持头低位-20°。对抗组兔在21d模拟失重期间每天保持45°头高位倾斜2h。实验结束后取股动脉和颈动脉进行组织学和ET-1免疫组化染色观察。结果光镜下可见模拟失重组兔股动脉内皮细胞脱落,管壁变薄,ET1-表达减少;颈动脉平滑肌细胞增生,弹力层增厚,ET1-表达增加;对抗组兔股动脉和颈动脉的组织形态学改变和内皮素表达与对照组相比无明显变化。结论21d模拟失重可引起兔股动脉发生萎缩性改变,ET1-表达下降;颈动脉发生增生性改变,ET1-表达增加。每天2h头高位45°可部分对抗模拟失重所引起的兔动脉结构和ET-1表达的变化。Objective To observe the effects of intermittent 45° head-up-tilt on endothelin （ ET-1 ） expression and morphological changes of femoral and carotid arteries in rabbits induced by 21 d simulated weightlessness. Method Twenty-four healthy male rabbits were randomly divided into control group, simulated weightlessness group and countermeasure group, 8 rabbits in each group. The simulated weightlessness group kept head-down tilt for 21 d, The countermeasure group was exposed to 45° head-up tilt for 2 h every day during 21 d head-down tilt. After 21 d experiment, structure of femoral artery and carotid artery were studied and ET-1 expression was tested by immunohistochemical method. Result Detachment of endothelial cells in femoral artery, necrosis of smooth muscle cells and decreased ET-1 expression were found in animals in the simulated weightlessness group, and the vessel wall became thinner. While hyperplasia of endothelial cells and thickened internal elastic lamina of the carotid artery were also observed. No significant changes were observed in femoral artery and carotid artery in animals of the countermeasure group. ET-1 expression decreased in femoral artery but increased in carotid artery in animals of the simulated weightlessness group, but no significant change was found in both femoral and carotid arteries in animals of the countermeasure group as compared with those in the control group. Conclusion Twenty-one days simulated weightlessness may induce an atrophic change and decreased ET-1 expression in femoral artery, and hyperplastic change and increased ET-1 expression in carotid artery in rabbits. Two-hour 45° head-up tilt every day may partly counteract the change in femoral artery and carotid artery induced by simulated weightlessness.

关 键 词：失重模拟 动脉 形态学改变 人工重力 内皮素 

分 类 号：R852.22[医药卫生—航空、航天与航海医学]