机械牵张对缺血缺氧离体培养心肌细胞形态的影响

Effects of mechanical stretch on cardiac myocyte morphological cultivated under ischemia and hypoxia in vitro

目的:在严重缺血缺氧时,细胞形态已受损的基础上,细胞接受力学刺激其形态变化如何?探讨机械牵张对缺血缺氧心肌细胞形态学的影响。方法:建立离体培养的心肌细胞机械牵张模型,以缺氧加无糖培养模拟烧伤早期缺血缺氧损害,心肌细胞形态变化采用F-actin荧光染色,利用图像分析系统分析细胞面积、长度。结果:缺氧3h后微丝破坏,失去正常网络状结构;缺氧12h部分微丝断裂,细胞收缩变形,细胞失去正常铺展外观。牵张3h细胞形态完好,与周边界限清楚,细胞面积增加,微丝沿细胞受力方向排列,局部呈增强趋势;牵张12h可见微丝沿受力方向排列,核周明显增强,胞体宽大。缺氧牵张3h微丝破坏明显,细胞形态不规则,胞浆内见空泡;缺氧牵张12h细胞形态严重受损,微丝结构几乎完全破坏,细胞铺展面积变小,细胞完整性严重受损。牵张12h细胞面积增加达22.4%,长度增加19.59%,缺氧牵张12h后细胞面积则减少22.1%。结论:机械牵张加重了缺血缺氧对心肌细胞的破坏。

AIM:To investigate how is the morphology changed after cells stimulated, during the major ischemia and hypoxia, and on the basis of injured cellular morphology,so as to study the effects of mechanical stretch on cardiac myocyte morphology in the combination with ischemia and hypoxia. <METHODS:The models of mechanical stretch of cardiac myocyte in vitro were established. An early injury of ischemia and hypoxia was simulated with the cultivation of ischemia and no sugar.The changes of cardiac myocyte morphology were observed by F actin immunofluorescence and statistical analysis was also carried out by image analysis system for area and length.<RESULTS:After three hour hypoxia,microfilament was damaged severely and lost the normal structure.After twelve hour hypoxia, part of microfilament was damage,the cell contracted and deformed and lost the normally spreading appearance.After three hour static stretch,cellular morphology was complete,the verge was obvious and the area of cell was enlarged. Microfilament was lined as the strength,which could be seen from the increased ratio.After twelve hour static stretch,part of microfilament was lined as the strength,the outline was enlarged obviously,and the soma was wide.After three hour hypoxia and stretch,microfilament was damaged obviously,cellular morphology was anomalous,and vacuole was seen in the cytoplasm.After three hour hypoxia and stretch,microfilament was damaged severely,microfilament was damaged completely,the spreading area of cell was shortened,and the whole cell was damaged severely.During twelve hour stretch,the area of cell was increased 22.4% and lengthened to 19.59% ,while the area of cell was decreased 22.1% after twelve hour hypoxia and stretch. <CONCLUSION:Mechanical stretch worsens the damage of cardiac myocyte, which is caused by ischemia and hypoxia.