模拟失重及高+Gx对猕猴心肌超微结构、血浆内皮素-1及C-反应蛋白的影响

Effects of Simulated Weightlessness and High +Gx Load on Myocardial Ultrastructure,Plasma Endothelin-1 and C-reactive Protein in Rhesus Macaque

目的:探讨30天模拟失重后高+Gx过载对猴猴心肌超微结构、血浆内皮素-1及C反应蛋白的影响,来研究模拟失重超重对心血管的影响,本实验为研究抗荷服和飞船轨道运行段应急返回超重医学提供实验数据。方法:15只雄性猕猴随机分为5组,即模拟失重组(对照组,A),+13 Gx/230 s组(B),模拟失重超重组+11 Gx/270 s(C),模拟失重超重组+13 Gx/230 s(D)和模拟失重超重组+15 Gx/200 s(E)。动物放血处死,抽取血液测定血浆内皮素-1及C反应蛋白的含量,组织取材后经戊二醛固定,制成电镜标本,观察猴心肌超微结构的变化。结果:C组、D组和E组血浆内皮素-1及C反应蛋白含量较A组升高,有统计学意义(P<0.05),C、D、E组之间无统计学意义(P>0.05)。D组血浆内皮素-1及C反应蛋白含量较B组升高,有统计学意义(P<0.05)。电镜下A组可见线粒体双层膜结构清晰,线粒体嵴清晰;B、C、D组部分线粒体出现双层膜结构消失,嵴数量减少;E组线粒体出现水肿、空泡样变,肌节断裂。结论:(1)失重后超重+13 Gx可引起心肌轻微损伤,失重后超重+15 Gx心肌损伤严重,且损伤程度随着+Gx值的增加而加重。(2)失重后超重比单纯超重心肌损伤严重。(3)本实验为超重耐力研究和提出科学合理的飞船轨道运行段应急返回超重医学提供实验支持。

Objective： To explore the effects of simulated weightlessness 30 days and high ＋ Gx overload on myocardial ultrastructure,plasma endothelin-1 and c-reactive protein in rhesus macaque,to study simulated weightlessness and overweight on the effect of cardiovascular,this experiment can provide experimental data for the Study of anti-G suits and spacecraft orbit segment emergency return overweight medicine.Methods： Fifteen male rhesus macaque are randomly divided into five groups： simulated weightlessness group（control group,A）,＋13 Gx/230 s group（B）,＋11 Gx/270 s exposure after simulated weightlessness group（C）,＋13 Gx/230 s exposure after simulated weightlessness group（D）,＋15 Gx/200 s exposure after simulated weightlessness group（E）.The animals are sacrificed to extract blood to measure plasma endothelin-1 and c-reactive protein content.The tissues are fixed by glutaraldehyde and made into electron microscopy specimens to observe the change of myocardial ultrastructure in rhesus macaque.Results： The content of group C,D and E plasma endothelin-1 and C-reactive protein increase than group A,there is statistically significant（P 0.05）,there is no statistical significance between the group C,D,E.The content of group D plasma endothelin-1 and C-reactive protein increase than group B,there is statistically significant（P0.05）.In the electron microscope,group A visible mitochondria bilayer structure clear and mitochondrial cristae clear;part of the mitochondrial bilayer structure disappeared and the number of mitochondrial cristae reduce in the group B,C,D.group E mitochondrial edema,vacuolar degeneration,sarcomere fracture.Conclusion：（1） ＋13 Gx exposure after simulated weightlessness can cause myocardial minor injuries,＋15 Gx exposure after simulated weightlessness can cause myocardial serious injury,along with the increase of ＋Gx load level,the severity of myocardial injury increased.（2） The myocardial injury of overweight after weightlessness is serious than simply overweight.（3） This study can provide experimental support for overweight endurance studies and scientific and rational spacecraft orbit segment emergency return overweight medical.