间断性头高位对模拟失重兔股静脉及颈静脉组织形态变化的影响  

Effects of Intermittent Head-up Tilt on Histomorphological Changes of Femoral Vein and Jugular Vein in Rabbits under Simulated Weightlessness

作　　者：孙会品[1] 孙喜庆[1] 王冰[1] 姚永杰[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医学系,陕西西安710032

出　　处：《航天医学与医学工程》2005年第6期410-414,共5页Space Medicine & Medical Engineering

基　　金：国家自然科学基金资助(30000197)

摘　　要：目的观察间断性头高位45°对21d模拟失重兔股静脉及颈静脉组织形态的影响。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。模拟失重组在21d实验期间保持头低位-20°。对抗组在21d模拟失重期间每天保持45°头高位倾斜2h。实验结束后取股静脉和颈静脉进行光镜和透射电镜观察。结果光镜下可见模拟失重组股静脉内皮细胞脱落,平滑肌细胞层萎缩,管壁变薄;颈静脉内皮细胞增生,弹力层增厚;对抗组静脉的组织形态学改变与对照组比较变化不明显。透射电镜下可见模拟失重组股静脉平滑肌细胞线粒体肿胀,染色质边集;颈静脉平滑肌细胞内质网发达,向分泌型转变;对抗组静脉的超微结构与对照组比较变化不明显。结论21d模拟失重可引起兔股静脉发生萎缩性改变,颈静脉发生增生性改变;每天2h头高位45°可部分对抗模拟失重所引起的股静脉及颈静脉结构的改变。Objective To observe the effects of intermittent head-up tilt on histomorphological changes of femoral vein and jugular vein in rabbits under 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. Rabbits in simulated weightlessness group were kept head-down tilt -20° for 21 d. Those in the countermeasure group were kept 45° head-up tilt for 2 h every day during 21 d head-down tilt. After the 21 d experiment, microstructure of femoral vein and jugular vein were studied under light microscope and transmission electron microscope. Result Exfoliated endothelial cells in the endothelium and necrotic changes in smooth muscle cells were found in femoral vein and vessel wall became thinner. While hyperplasia of endothelial cells and thickened internal elastic lamina were found in jugular vein in rabbits of simulated weightlessness group. No significant changes were observed in femoral vein and jugular vein in rabbits of the countermeasure group. When observed by transmission electron microscope, swelling of mitochondria, and gathering of chromatin around the karyotheca were found in smooth muscle cells of the femoral vein. Quantity of endoplasmic reticulum in smooth muscle cells in the jugular vein increased and the cells turned into excretory type in rabbits of the simulated weightlessness group. The ultrastructure of femoral vein and jugular vein in rabbits of countermeasure group showed no obvious differences with those of control group. Conclusion Twenty-one-day simulated weightlessness may induce a hyperplastic change in femoral vein and atrophic change in jugular vein of rabbit. Two-hour 45°head-up tilt every day may partly counteract the changes induced by simulated weightlessness.

关 键 词：模拟失重 头高位倾斜 股静脉 颈静脉 超微结构 

分 类 号：R852.22[医药卫生—航空、航天与航海医学]