周期性牵张力对骨髓破骨细胞形成的影响

Effects of the cyclic-tension force on the formation of osteoclast in rat bone marrow culture

目的 :通过大鼠骨髓破骨细胞的体外诱导培养 ,观察不同时段周期性牵张力对骨髓破骨细胞形成的影响。方法 :通过体外细胞培养加载系统 ,选择频率为 6周 /min ,弹性基底膜发生 12 %形变率的周期性牵张力。试验共分为 4组 ,A组 :为对照组 ,在整个培养期间不加力 ;B组 :从培养的第 2d开始加力 ,连续加力 3d ;C组 :从培养的第 2d开始加力 ,连续加力 5d ;D组 :从培养的第 5d开始加力 ,连续加力 2d。每组各 6孔 ,均于培养的第 7d进行多核细胞计数。结果 :B组、C组多核细胞数量与对照组相比明显减少 (P <0 .0 5 ) ,而D组多核细胞数量与对照组相比无显著性差异 (P >0 .0 5 )。B组与C组相比亦无显著性差异。结论 :周期性牵张力主要是在骨髓诱导培养的早期抑制破骨细胞的形成 ,后期施力对破骨细胞的形成无明显影响。

Objective:To investigate the effect of the cyclic-tension force on the osteoclast formation in rat bone marrow culture, so as to learn about the mechanisms of bone remodeling under mechanical strain.Method:Osteoclast formation was assessed in marrow cultures plated on flexible membranes subjected to 12% elongation by strain unit at 6 cycles/min (i.e. 5-s elongation and 5-s relaxation) in different duration. Result: Cultures strained during days 2 through 7 inhibited osteoclast formation, a degree of inhibition similar to that observed when the cultures were subjected to strains during only days 2 through 4 but also evaluated on day 7. In contrast, straining of culture during days 5 through 7 had little influence on inhibiting the formation of osteoclast.Conclusion: the cyclic-tension force mainly in early stage inhibit the formation of osteoclast in rat bone marrow culture. The results suggest that mechanical strain must be considered as inhibitory to osteoclast recruitment.