TGF-β1和CTGF在周围神经卡压后骨骼肌纤维化中的作用

Effect of TGF-β1 and CTGF on skeletal muscle fibrosis in nerve compression

目的研究TGF-β1和CTGF在周围神经卡压后骨骼肌纤维化中的表达及与I型胶原纤维沉积的关系，并探讨其在周围神经卡压后骨骼肌纤维化中的作用。方法取清洁雄性SD大鼠50只，随机分为A组（假手术组，仅分离暴露坐骨神经）和B组（坐骨神经慢性卡压组）。术后2、4、6、8和10周，切取各组大鼠卡压侧腓肠肌，行苏木精-伊红、Masson、免疫组化染色和RT—RCR、Westernblot检测，观察腓肠肌萎缩和纤维化程度以及TGF-β1、CTGF和I型胶原纤维的表达情况。结果在各取材时间点B组与A组相比，肌纤维萎缩，细胞外基质中胶原纤维随卡压时间延长逐渐增多；TGF-β1和CT-GF的表达在卡压初期逐渐缓慢升高，于6周左右达到高峰，其后缓慢下降，仍维持长时间高表达。结论周围神经卡压后其支配的骨骼肌发生纤维化；在纤维化过程中，骨骼肌组织中TGF-β1和CTGF的表达显著上调，且长时间高表达，I型胶原纤维的沉积与TGF—β1和CTGF的表达有关，TGF-β1和CTGF在周围神经卡压后骨骼肌纤维化中发挥重要作用。

Objective To investigate expression of TGF-β1, CTGF and collagen deposition in skeletal muscle during chronic entrapment of peripheral nerve. Methods Fifty rats were separated into two groups, control group and experimental group. At different time points after operation, the right gastrocnemius of 5 rats from each group were collected for further analysis such as HE, Masson stain, immunohistochemical staining, RT-PCR and Western-blot. Results It was observed that axon degeneration occurred during chronic nerve entrapment, and which was in line with reports from other groups. Moreover, it had been demonstrated that after nerve entrapment, skeletal muscles may form fibrosis and degeneration consequently. Within this pathological procedure, expression of TGF-β1. CTGF and deposition of collagen I changed rapidly when compared with control group. Conclusion Overall, these results indicated that these factors may be important during skeletal muscle degeneration after chronic nerve entrapment.