模拟失重大鼠去内皮股动脉血管反应性的变化  

The alterations in vasoreactivity of endothelium removed femoral arteries isolated from simulated weightlessness rats

作　　者：马进[1] 任新玲[2] 程九华[1] 马孝武[1] 张立藩[1] 杨天德[3] 

机构地区：[1]第四军医大学航空航天生理学教研室,西安710032 [2]西京医院呼吸内科 [3]航天医学工程研究所,北京100094

出　　处：《中华航空航天医学杂志》2003年第4期200-203,共4页Chinese Journal of Aerospace Medicine

基　　金：国家自然科学基金资助项目 (3 980 0 15 7;3 0 170 3 5 5 )

摘　　要：目的　探讨模拟失重所致股动脉平滑肌反应性变化的特征与机制。　方法　通过尾部悬吊大鼠 4周模拟失重生理影响 ,利用离体去内皮股动脉血管环测定股动脉对血管活性物质的反应。　结果　模拟失重大鼠去内皮股动脉环对多种血管活性物质的收缩反应均明显降低。受体介导的股动脉收缩反应 ,如苯肾上腺素 ( 10 -6～ 10 -4mol/L)、内皮素 1( 10 -8～ 10 -7mol/L)及血管加压素 ( 10 -9～ 10 -7mol/L)诱发的收缩反应 ,在模拟失重 4周后均明显降低 ;非受体介导的收缩反应 ,如氯化钾( 4 0～ 80mmol/L)、氯化钙 ( 10 -5～ 5× 10 -3 mol/L)及钙离子载体A2 3187( 10 -6mol/L)激发的收缩反应在模拟失重 4周大鼠组亦明显较对照大鼠减弱。而去内皮股动脉环对硝普钠 ( 10 -9～ 10 -4mol/L)与环磷酸鸟苷 ( 10 -7～ 10 -3 mol/L)的舒张反应在模拟失重大鼠与对照大鼠间没有明显差别。去内皮股动脉对氯化钾、苯肾上腺素、血管加压素、内皮素 1、硝普钠与环磷酸鸟苷反应的敏感性在模拟失重大鼠与对照大鼠间亦没有明显差别。　结论　 4周模拟失重后大鼠去内皮股动脉受体介导与非受体介导的收缩反应均减弱 ,提示Objective The aim of this study was to investigate the nature of altered femoral arterial responsiveness in rats underwent simulated microgravity. Methods Rats were subjected to tail suspension for 4 weeks to simulate microgravity, and responses of endothelium removed femoral arterial rings isolated from tail suspended and control rats to vasoactive compounds were examined in vitro. Results Receptor mediated contractile responses of femoral arterial rings evoked by phenylephrine (10 -6 ～10 -4 mol/L), endothelin 1(10 -8 ～10 -7 mol/L), vasopressin (10 -9 ～10 -7 mol/L) in tail suspended rats were significantly lower than those of control rats. Non receptor mediated contractile responses of femoral arterial rings induced by KCl (40～80 mmol/L), CaCl 2 (10 -5 ～5×10 -3 mol/L) and Ca 2+ ionophore A23187 (10 -6 mol/L) were also decreased in tail suspension rats as compared with those of controls. But the differences of vasodilatory responses induced by SNP (10 -9 ～10 -4 mol/L) and cGMP (10 -7 ～10 -3 mol/L) between two groups were non significant. The sensitivity (EC 50 ) to these above vasoactive compounds showed no significant differences between the two groups. Conclusion It is suggested that the diminished contractile responsiveness is mainly the result of altered contractile apparatus, especially the contractile proteins, and altered signal transduction may play less important role in the changes of contractile responsiveness.

关 键 词：失重模拟 股动脉 血管收缩 大鼠 

分 类 号：R85[医药卫生—航空、航天与航海医学]