神经生长因子在后交叉韧带重建移植物中的表达及其意义

Expression of nerve growth factor in posterior cruciate ligament grafts and its significance

目的:探讨神经生长因子(NGF)在后交叉韧带重建移植物中的表达及其对韧带重建进程的影响。方法:将24只比格犬切断双后肢膝关节后交叉韧带,以拇趾长屈肌肌腱为移植物重建后交叉韧带,其中一侧用跟腱腱周组织包绕移植物为实验组,对侧不做包绕作为对照组,术后4周、8周、12周分别各取8只犬移植物,观察移植物组织、细胞免疫组化NGF的表达变化,并比较两组NGF免疫组化平均光密度,探讨免疫组化NGF的表达变化对移植物组织、细胞影响。结果:实验组术后4周,移植物表面有间皮细胞,间皮细胞内层是增生的纤维细胞和血管内皮细胞,类似滑膜组织;术后8周大量血管增生,成纤维细胞数量较前增多,排列较前规律;术后12周,纤维细胞较前减少,排列更为规律;对照组术后4周、8周、12周移植物有少量纤维细胞增生,细胞排列不规律,移植物仅有少量血管长入。两组NGF免疫组化平均光密度比较,在术后第4周、8周、12周差异均有统计学意义(均P<0.01)。结论:腱周组织包绕移植物重建后交叉韧带,NGF表达明显升高,移植物血管生成增多,可促进成纤维细胞增殖、迁移,加快再血管化及移植物重建进程。

Objective：To investigate the expression of nerve growth factor（NGF）in posterior cruciate ligament（PCL）graft and its effect on ligament reconstruction.Methods：PCL was reconstructed with flexor hallucis longus（FHL）wrapping the peritendon tissues of Achilles tendons in 24 Beagle dogs（experimental group）and with simple tendon autograft（control group）.After 4,8 and 12 weeks,the histological changes of autograft and NGF protein expression detected by immunohistochemistry were observed and compared.Results：In the experimental group,there were mesothelial cells on the surface of the graft at 4 weeks after operation.The inner layer of the mesothelial cells was hyperplastic fibroblasts and vascular endothelial cells,which resembled synovial tissue.After 8 weeks,a large number of blood vessels and fibroblasts were observed.Moreover,the pattern of fibroblasts was more regular.At 12 weeks after operation,the number of fibroblasts was decreased,but its pattern was more regular than before.Less fibroplastic proliferation,few blood vessels in the graft and cells with irregular arrangement were presented in the control group at week 4,8 and 12 after transplantation.There was a significant difference in the average optical density of NGF between the two groups at week 4,8 and 12 post-operation（P〈0.01）.Conclusion：Application of the additional peritendon tissues of Achilles tendons wrapping autograft in PCL reconstruction could enhance NGF level,facilitate vascularization,and promote fibrocyte migration and proliferation in grafts.