目的分离培养大鼠肌腱干细胞（tendon stem cells，TSCs）并检测其干细胞特性，观察拉力对大鼠TSCs Sox-9基因和蛋白表达的影响。 方法取SPF级12周龄SD大鼠两侧髌腱，胶原酶消化，以低密度接种分离出TSCs并传代，倒置相差显微镜观察细胞形态，结晶紫染色观察克隆形态和数量，流式细胞术检测其MSCs表面标记进行鉴定。体外力学加载仪对第3代TSCs施加4%、0.17 Hz的拉力作为实验组，对照组TSCs未进行拉力加载，分别采用实时荧光定量PCR和Western blot法检测拉力对TSCs Sox-9基因和蛋白表达的影响。 结果倒置相差显微镜观察示，分离出的原代细胞主要呈星状，第1代细胞呈纤维细胞状。分离出的细胞7 d后形成单细胞克隆；流式细胞仪检测示其CD29、CD44、CD90表达阳性，CD45表达阴性。荧光定量PCR和Western blot法检测示，与对照组相比，实验组拉力加载后4 h Sox-9基因水平下调、蛋白表达明显降低，24 h Sox-9基因水平上调、蛋白表达明显增多，差异均有统计学意义（P＜0.05）。 结论成功分离大鼠TSCs且符合MSCs特性；拉力刺激初始抑制了Sox-9表达，但拉力刺激完全消失后Sox-9表达上升
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