声带损伤后自身修复特点研究

Characterization of vocal fold wound healing in a rabbit model

目的通过研究兔声带固有层损伤后不同时期组织病理及主要细胞外基质(extra cellular matrix,ECM)的变化情况,探讨声带损伤后的自身修复特点。方法对实验用兔声带行锐性损伤深达声韧带,于术后3 d～12个月观察声带形态学变化,HE染色、Masson染色、Alcian Blue染色及免疫组化染色,观察声带组织学结构变化及固有层内胶原、透明质酸及纤维连接蛋白等主要ECM的分布及含量变化。结果兔声带损伤后3 d～3个月成纤维细胞明显增加,40 d～12个月纤维组织持续增生,12个月声带局部无分层结构。ECM中胶原在损伤后3 d～12个月含量均明显高于正常对照组(P<0.05),在固有层内不规则紊乱分布;透明质酸在损伤后40 d内含量有增加趋势,其后降低至正常对照组水平;纤维连接蛋白在损伤后40 d～12个月时含量均高于正常对照组(P<0.05),散在分布于固有层各层。结论兔声带损伤后,在损伤早、中期各种ECM分泌增加,主要表现为以胶原为主的纤维组织明显增多且呈无序排列,透明质酸略有增加,纤维连接蛋白明显增加;在损伤后期胶原和纤维连接蛋白含量持续高于正常,声带局部瘢痕形成。

Objective To investigate the characteristics of vocal fold wound healing by studying the changes in histopathology and the major extra cellular matrix（ECM） after vocal fold lamina propria injuring in a rabbit model. Methods Using a telescope for guidance,we made an incision in the middle region of the vocal fold tissue in 12 rabbits.Larynges were harvested at 3,15,40 days and 3,6,12 months after operation.We performed HE staining for histopathologic research,and used Masson trichrome staining for collagen,Alcian Blue staining for hyaluronic acid and immunohistochemical staining for fibronectin. Results After injury,the formation of new capillaries and inflammatory cells infiltration occurred within 15 days,fibroblasts increased significantly form 3 days to 3 months,fibrous tissues persistently increased from 40 days to 12 months,12 months after injuring,the vocal folds had no hierarchical structure in local position.In addition,the content of collagen were significantly higher than normal（P0.05） after injury,collagen had an irregular disordered distribution in the lamina propria.Hyaluronic acid had less increase,its content and distribution showed no significant difference with the normal control.Fibronectin scattered in the lamina propria,its levels were obviously higher than normal（P0.05） from 40 days to 12 months after injury. Conclusion In the early and middle period of vocal fold wound healing,the ECM in the lamina propria increased,collagen increased significantly and deposited disorderly,hyaluronic acid less increased,fibronectin obviously increased;in the late period,collagen and fibronectin levels were continuously higher than normal,disordered collagen fibers arranged in vocal fold scar.