聚己内酯/聚乳酸膜防止硬膜外瘢痕粘连的实验研究

Eperimental study on the prevention of epidural scar adhesion with polycaprolactone/polylactic acid membrane

目的探讨将聚己内酯／聚乳酸(polycaprolactone／polylactic acid,PCL／PLA)膜置于硬膜外,以减少硬膜外瘢痕粘连的方法。方法用大鼠96只,L1、L3全椎板切除,分为空白对照组、自体游离脂肪片组及PCL／PLA膜组3组。术后1、3、6、12周处死动物。对硬膜外瘢痕形成及粘连做大体及组织学观察,逆转录,聚合酶链式反应(RT-PCR)方法检测硬膜外瘢痕中转化生长因子β(TGF-β)的表达,并用免疫组化法及RT-PCR法检测相应脊髓中P物质、c-fos的表达。结果与空白对照组相比,PCL／PLA膜组硬膜外瘢痕粘连减轻,术后3周及6周时硬膜外瘢痕组织中TGF-β表达量明显减少,脊髓中P物质、c-fos表达减少;脂肪片早期可减轻硬膜外瘢痕粘连,但后期粘连也有所加重,脊髓中P物质、c-fos表达也有相应改变。结论聚己内酯／聚乳酸膜可减轻硬膜外的瘢痕形成及粘连,使脊髓中疼痛介质P物质、c-fos表达减少,有助于防止术后腰腿痛的复发。

Objective To evaluate the ability of a polycaprolactone/polylactic acid (PCL/PLA) membrane to inhibit epidural scar adhesion after laminectomy, and observe the responsive changes of the pain media in the spinal cord. Methods L1 , L3 laminectomies were performed on 96 Wister rats. The rats were divided into 3 groups: Noneimplant Control Group (NC) , Autologous free fat graft group ( AFFG) and PCL/PLA membrane group ( PCL/PLAm) . The rats were killed at 1, 3, 6, and 12weeks postoperatively. Epidural scar formation and adhesion were observed grossly and histologically. Reverse transcription polymerase chain reaction ( RT-PCR) were used to analyses the expression of Transforming growth factor beta (TGF-p) in the epidural scar. Immunohistochemistry stain and RT-PCR were performed to evaluate the expression of the substance P and the c-fos gene in the relevant spinal cord, and the results were analyzed statistically. Results Gross evaluation and histological evaluation showed that in the NC lamina defect site had much scar tissue and had wide and tight adhesions to the dura; in the AFFG, with the fat degrading gradually, the adhesions were increased; whereas in the PCL/PLAm group,there were slightly adhesions to the dura. RT-PCR showed that the expression of the TGF-p was much less in the PCL/PLAm group than in the NC group. The insertion of the PCL/PLA membrane and the fat patch reduced the expression of the substance P and the c-fos gene in the spinal cord. Conclusion The insertion of the PCL/PLA membrane reduces scar formation and seperates fibrosis tissue from the dura, the results indicate that PCL/PLA membrane is an effective way of reducing peridural scar formation and preventing the failed back surgery syndrome.