机械压力及细胞内钙释放通道阻滞对髁突软骨细胞骨架影响的研究

Effect of Mechanical Pressure on Cytoskeletal Structure in Rabbit Mandibular Condylar Chondrocytes and the Function of Intracellular Calcium Release Channel Block in it.

目的 :探讨髁突软骨细胞骨架随力学刺激的变化过程及其是否受到细胞内钙及其IP3 通道的影响。方法 :消化法培养 2周新西兰白兔的髁突软骨细胞 ,用自行设计制作的可控液压细胞加载装置分别在 90kPa压强下加载6 0min、36 0min、2 0g/L肝素阻断处理后再分别进行 90kPa压强下加载 6 0min、36 0min ,考马斯亮蓝染色方法观察各实验组细胞骨架形态的变化特征。结果 :对照组MCC细胞骨架系统显示为围绕胞核呈丝网状紧密有序排列 ,弥散性颗粒较均匀地分布其中 ;90kPa加压 6 0min后MCC细胞骨架增多且排列致密 ;加压时间延长至 36 0min时 ,MCC细胞骨架表达较 6 0min时减弱 ,且多呈网状排列结构 ;IP3 通道阻断后 ,再经 90kPa加压 6 0min ,MCC细胞骨架收缩聚集于胞膜周边 ,呈现稀疏、不连续的排列状态 ;加压时间延长至 36 0min时 ,MCC细胞骨架有序的网状结构重新出现 ,有些细胞出现特征性“鸟喙”样改变。结论 :MCC细胞骨架系统参与了髁突软骨细胞力学信号转导过程 ,适宜的压力可使骨架表达增强、排列致密 ,在此机械力导致MCC细胞骨架的重排过程中 ,细胞内钙及其IP3

Objective: To investigate the change of cytoskeletal structure under the mechanical pressure and the effects of intracellular calcium release channel block on that process in rabbit mandibular condylar chondrocytes(MCC). Methods: In vitro cultured MCC from two-week-old New Zealand rabbits were incubated under continuous pressure of 90 kPa for 60min, 360min by hydraulic pressure controlled cellular strain unit designed by ourselves, with or without blocking the intracellular calcium release channel by 20g/L heparin. Coomassie BB staining was used to observe the characteristics of cytoskeletal structure in different groups. Results: The cytoskeleton of cultured MCC was revealed correspondingly uniform and tight network-like structure in the cytoplasm. Continuous pressure of 90kPa for 60min caused cytoskeleton increased and arranged even tighter. When the pressure time prolonging to 360min, the cytoskeleton of MCC expressed decreasingly with network-like structure. Blocking the intracellular calcium release channel by 20g/L heparin, which was inositol triphosphate receptor inhibitor, The cytoskeleton of MCC under 90kPa for 60min showed sparsely, discontinuously and concentrating around the cytomembrane. But the uniform and tight network-like structure reappeared in most MCC with the pressure time increased to 360min and some individual cells showed typical change of 'bird mouth-like', which means the shrinking and adherence to the membrane, as well as the change of the shape and function of those cells. Conclusion: The cytoskeletal system participates in the transition process of mechanical signal to biological effect in MCC. Feasible pressure could cause it increased and arranged even tighter. Intracellular calcium and its inositol triphosphate receptor channel may play an important role in the recomposition process of MCC cytoskeleton under mechanical pressure.