模拟失重下兔股静脉应力-应变关系及其相关组织形态学变化
http://www.100md.com
2005年2月26日
模拟失重下兔股静脉应力-应变关系及其相关组织形态学变化
岳勇 姚永杰 杨志军 谢小萍 王冰 朱庆生 孙喜庆 吴兴裕
(710032 西安，第四军医大学航空航天医学系)
【摘要】 目的 观察模拟失重对兔股静脉应力-应变关系的影响及股静脉的组织形态学变化。 方法 建立头低位(-20°)倾斜的模拟失重家兔模型。24只雄性健康新西兰兔，随机分为模拟失重21d组、模拟失重10d组和对照组，每组8只。各组取股静脉各做成血管条及血管环并分别做轴向和环向拉伸实验；对照组和实验组的血管试样均行显微结构观察。 结果 随着载荷应力的增加，血管试样的轴向和环向形变均显著增加(P<0.01)，卸载时，均显著减少(P<0.01)，相同应力下，3组试样的轴、环向卸载形变均较加载时增大(P<0.05)，存在明显滞后环。相同应力(轴向：0～2 g；环向0.5～1 g)下，HDT-21d及HDT-10d组的轴、环向加卸载形变均较对照组显著增加，且HDT-21d组较HDT-10d组仍有显著增加。组织形态学观察表明，模拟失重时股静脉的管壁材料组份及结构均发生变化，内皮细胞呈矮柱或立方状，并伴有部分内皮细胞脱落，平滑肌层变薄等萎缩性改变。 结论 模拟失重后股静脉顺应性明显增加，且21d 组较10d组增加更显著，同时股静脉管壁的组织结构发生明显改变，这可能是其顺应性增加的重要原因之一。
, http://www.100md.com
【关键词】 失重模拟； 顺应性； 股静脉； 应力-应变； 显微结构； 拉伸实验
【中图分类号】 R852.22
Stress-strain relationship of femoral vein in rabbits after simulated weightlessness and its histomorphological changes YUE Yong, YAO Yong-jie, YANG Zhi-jun, et al. Faculty of Aerospace Medicine, Fourth Military Medical University, Xi'an 710032, China
【Abstract】 Objective To observe the effect of simulated weight1essness on stress-strain relationship of femoral vein and to investigate the structural changes of femoral vein in rabbits. Method The head-down tilt (-20°) (HDT) rabbit weightlessness simulation model were set up. Twenty four healthy male New-Zealand rabbits were randomly divided into HDT-2l d group, HDT-10 d group and control group. Femoral vein strips and rings were taken from 3 groups of rabbits for uniaxial tensile test. The microstructure of femoral vein were observed. Results With the increase of load stress, longitudinal and circumferential strain of vein samples from 3 groups increased significantly (P<0.0l), and in the course of unloading, they decreased obviously (P<0.01). The longitudinal and the circumferential strains in the course of unloading increased more obviously than those in the course of loading at the same stress. Under the same stress, the longitudinal or circumferential strain of HDT-21 d group and HDT-10 d group increased more obviously than that of control, and that of HDT-21 d increased more obviously than that of HDT-10 d. The components and structure of femoral vein wall of HDT-rabbits changed significantly as compared with that of controls. Some endothelium ce1ls of femoral vein became short and columnar or cubic, some of which fell off and smooth muscle layer became thinner. Conclusions The femoral venous compliance increase significantly after weightlessness-simulation, and the structure of femoral vein wall changed obviously. The structural changes may be one of the important reasons of femoral vein compliance increase.
【Key words】 Weightlessness simulation; Comp1iance; Femoral vein; Stress-strain; Microstructure; Tensile test, http://www.100md.com
岳勇 姚永杰 杨志军 谢小萍 王冰 朱庆生 孙喜庆 吴兴裕
(710032 西安，第四军医大学航空航天医学系)
【摘要】 目的 观察模拟失重对兔股静脉应力-应变关系的影响及股静脉的组织形态学变化。 方法 建立头低位(-20°)倾斜的模拟失重家兔模型。24只雄性健康新西兰兔，随机分为模拟失重21d组、模拟失重10d组和对照组，每组8只。各组取股静脉各做成血管条及血管环并分别做轴向和环向拉伸实验；对照组和实验组的血管试样均行显微结构观察。 结果 随着载荷应力的增加，血管试样的轴向和环向形变均显著增加(P<0.01)，卸载时，均显著减少(P<0.01)，相同应力下，3组试样的轴、环向卸载形变均较加载时增大(P<0.05)，存在明显滞后环。相同应力(轴向：0～2 g；环向0.5～1 g)下，HDT-21d及HDT-10d组的轴、环向加卸载形变均较对照组显著增加，且HDT-21d组较HDT-10d组仍有显著增加。组织形态学观察表明，模拟失重时股静脉的管壁材料组份及结构均发生变化，内皮细胞呈矮柱或立方状，并伴有部分内皮细胞脱落，平滑肌层变薄等萎缩性改变。 结论 模拟失重后股静脉顺应性明显增加，且21d 组较10d组增加更显著，同时股静脉管壁的组织结构发生明显改变，这可能是其顺应性增加的重要原因之一。
, http://www.100md.com
【关键词】 失重模拟； 顺应性； 股静脉； 应力-应变； 显微结构； 拉伸实验
【中图分类号】 R852.22
Stress-strain relationship of femoral vein in rabbits after simulated weightlessness and its histomorphological changes YUE Yong, YAO Yong-jie, YANG Zhi-jun, et al. Faculty of Aerospace Medicine, Fourth Military Medical University, Xi'an 710032, China
【Abstract】 Objective To observe the effect of simulated weight1essness on stress-strain relationship of femoral vein and to investigate the structural changes of femoral vein in rabbits. Method The head-down tilt (-20°) (HDT) rabbit weightlessness simulation model were set up. Twenty four healthy male New-Zealand rabbits were randomly divided into HDT-2l d group, HDT-10 d group and control group. Femoral vein strips and rings were taken from 3 groups of rabbits for uniaxial tensile test. The microstructure of femoral vein were observed. Results With the increase of load stress, longitudinal and circumferential strain of vein samples from 3 groups increased significantly (P<0.0l), and in the course of unloading, they decreased obviously (P<0.01). The longitudinal and the circumferential strains in the course of unloading increased more obviously than those in the course of loading at the same stress. Under the same stress, the longitudinal or circumferential strain of HDT-21 d group and HDT-10 d group increased more obviously than that of control, and that of HDT-21 d increased more obviously than that of HDT-10 d. The components and structure of femoral vein wall of HDT-rabbits changed significantly as compared with that of controls. Some endothelium ce1ls of femoral vein became short and columnar or cubic, some of which fell off and smooth muscle layer became thinner. Conclusions The femoral venous compliance increase significantly after weightlessness-simulation, and the structure of femoral vein wall changed obviously. The structural changes may be one of the important reasons of femoral vein compliance increase.
【Key words】 Weightlessness simulation; Comp1iance; Femoral vein; Stress-strain; Microstructure; Tensile test, http://www.100md.com