摘要
为了解动物关节软骨对低加载速率的高应力载荷的即时损伤反应 ,在恒定应力速率下 ,对离体新鲜牛肩关节软骨组织块施加单次低应变速率的应力负荷 ,随后行组织块培养 ,应力峰值变化范围为 2～ 11MPa。通过FDA/PI双荧光染色法观察组织块受载 3天后软骨细胞损伤的程度及分布模式 ,并计算细胞死亡比例 ;SEM观察胶原超微结构。结果表明 ,自 5MPa开始 ,实验组软骨细胞的死亡比例均高于正常组 ,且随着应力峰值的增大而增加 ;实验组死亡细胞的分布比较广泛 ,应力峰值超过 9MPa的组织块的死亡细胞几乎分布于软骨全层。实验组与对照组均没有出现胶原结构的破坏。
To explore the mode of matrix and cell injury of articular cartilage subjected to high stress mechanical loads with a low rate of loading. Loads characterized by a constant stress rate of 0.26MPa/s to a peak stress between 2MPa and 11MPa being applied to the adult bovine articular cartilage explants was designated as the test groups. No mechanical loads were applied to the control group. All the explants were maintained in culture for the next few days after loads. The spatial patterns and severity of chondrocyte injury were determined using fluorescein diacetate and propidium iodide. Matrix damages were assessed by inspection of the microstructure of the collagen fiber network under SEM. When the peak stress was 5MPa and higher, the rate of cell death in the explants of test groups was significantly greater compared with controls, and the greater peak stress applied, the higher percentage of dead versus total cells was documented, and a more diffuse distribution of dead cells was observed. When the peak stress reached 9MPa, cell death involving full depth of the cartilage was observed in test groups . Damages to the collagen fiber network were not observed both in test and control groups. The results indicated that high stress mechanical loads with a low rate of loading resulted in more severe chonrocytes damage rather than collapse of collagen fiber network.
出处
《解放军医学杂志》
CAS
CSCD
北大核心
2003年第5期454-455,共2页
Medical Journal of Chinese People's Liberation Army
关键词
低加载速率
高应力载荷
关节软骨
即时损伤作用
超微结构
cartilage, articular
stress, mechanical
fluorescent dyes
microscopy, electron, scanning
