为探讨矫形治疗中髁突软骨增殖活性变化的机理，本研究采用流式 细胞术 检测胰岛素样生长因子-Ⅰ(IGF-Ⅰ)对体外培养的大鼠下颌髁突软骨细胞增殖活性的 影响。结 果显示，IGF-Ⅰ直接作用于培养的髁突软骨细胞24小时及96小时后，实验各组细胞的增殖 指 数（PI）均大于对照组（42.0±0.29及11.4±0.37），其中以100ng/ml组增大最多（48.9± 0.29及23.6±0.29）；而作用96小时后各实验组的PI较对照组增高 幅度更大。以上提示，IGF-Ⅰ是大鼠下颌髁突软骨细胞的促有丝分裂因子，其作用存在延 迟效应。 In order to explore the mechanism of condylar cartilage proliferation in orthopedic treatment, we examined the effect of insulin-like growth factor-Ⅰ (IGF-Ⅰ) on the proliferation of rat mandibular condylar chondrocytes cultured in vitro by flow cytometry. The results showed that the proliferation index (PI) of IGF-Ⅰ in cultured rat condylar chondrocytes was significantly higher than that in the control group (42.0 ± 0.29 and 11.4 ± 0.37) at 24 hours and 96 hours, respectively, with 100 ng / ml group increased most (48.9 ± 0.29 and 23.6 ± 0.29), while the PI of each experimental group increased more than the control group after 96 hours. The above suggests that IGF-Ⅰ is a mitogenic factor of rat mandibular condylar chondrocytes, and its effect has a delayed effect.