目的:研究骨髓间充质干细胞（MSC）在视网膜色素变性（RP）大鼠体内的分化。方法:Lewis大鼠腹腔注射30g/L NaIO₃ 100mg/kg,建立大鼠RP模型,将体外培养的MSC植入视网膜下腔,用免疫荧光标记的方法对MSC进行追踪,并观察术后第1,2,3,4,5wk MSC在该微环境中的分化。结果:术后第1wk即可见MSC位于视网膜色素上皮（RPE）层与光感受器细胞层,但全角蛋白（PCK）及rhodopsin标记阴性,第3wk开始可见MSC在体内表达PCK及rhodopsin。结论:MSC植入RP模型大鼠视网膜下腔后可存活,主要分布于RPE层和视锥、视杆细胞层,并表达RPE细胞和光感受器细胞的表面标志。

AIM:To assess the differentiation of rat mesenchymal stem cell（MSC） in the microenvironment of retinitis pigmentosa（RP） induced by the administration of sodium iodate. METHODS:In vitro cultured Lewis rat MSC were injected into the subretinal space of NalO₃ induced RP rat eyes（30g/L NalO₃100mg/kg）.To observe the trace and differentiation of MSC by immuno-fluorescent method successively in 5 weeks after the surgery. RESULTS:The majority of the transplanted cells stay in retinal pigment epithelium（RPE） layer and cones and rods layer.From the 2^nd week after transplantation,the engrafted MSC expressed PCK and rhodopsin under fluorescent microscope. CONCLUSION:MSC can survive mainly in the outer layer of retina in the microenvironment of RP and differentiate forward the RPE cell and photoreceptor.