目的 評(píng)價(jià)不同硬膜外覆蓋物以及局部應(yīng)用類固醇激素對(duì)腰椎術(shù)后瘢痕形成的影響，并初步探討其機(jī)制。方法 Wistar大鼠80只隨機(jī)數(shù)字表法分為4組：膠原海綿＋地塞米松組、膠原海綿組、明膠海綿組和對(duì)照組（無(wú)任何硬脊膜外覆蓋物），每組實(shí)驗(yàn)動(dòng)物20只，麻醉后在背部正中做切口行L1-L5全椎板切除，造成0.5 cm×1.0 cm骨性缺損，顯露硬膜。膠原海綿＋地塞米松組動(dòng)物硬膜外放置膠原海綿并注射0.1 mL地塞米松，膠原海綿組動(dòng)物硬膜外放置膠原海綿，明膠海綿組動(dòng)物硬膜外放置明膠海綿，對(duì)照組直接縫合肌肉組織。手術(shù)后12周重新切開(kāi)傷口，觀察硬膜外瘢痕形成及與硬脊膜粘連情況。應(yīng)用免疫組化和Western blot檢測(cè)顯示硬膜外瘢痕及周圍組織中TGF-β1、VEGF表達(dá)情況，比較各組間差異。結(jié)果 肉眼及光鏡觀察膠原海綿＋地塞米松組和膠原海綿組的硬膜外瘢痕粘連明顯少于明膠海綿組和對(duì)照組，而膠原海綿＋地塞米松組與膠原海綿組之間無(wú)顯著差異，明膠海綿組與對(duì)照組間無(wú)顯著差異；免疫組化及Western blot檢測(cè)顯示膠原海綿＋地塞米松組和膠原海綿組硬膜外瘢痕及周圍組織中TGF-β1、VEGF的表達(dá)顯著少于明膠海綿組和對(duì)照組，而膠原海綿＋地塞米松組與膠原海綿組之間、明膠海綿組與對(duì)照組之間均無(wú)明顯差異。結(jié)論 膠原海綿可以顯著降低實(shí)驗(yàn)大鼠腰椎術(shù)后硬膜周圍瘢痕增生粘連的形成，同時(shí)加用局部注射地塞米松并沒(méi)有加強(qiáng)這種作用；局部應(yīng)用明膠海綿不能減少硬膜外瘢痕增生粘連的形成。膠原海綿應(yīng)用后局部的TGF-β1和VEGF的低表達(dá)可能是減少硬膜外瘢痕增生粘連的重要機(jī)制之一。

Objective To evaluate the effect of different epidural covering objects and local usage of steroid hormone on scar formation after spinal operation and to explore its mechanism. Methods Wistar rats (80) were randomly divided into four groups: collagen sponge + Dexamethasone (Dex) group, pure collagen sponge group, gelatin sponge group, and control (no epidural covering) group. After anesthesia, incisions were made in the middle of rat back, L1-L5 laminectomy was performed to leave 0.5 cm × 1.5 cm defects on the dura matter. Epidural placement of collagen sponge and Dex (0.1 mL) was given to rats in collagen sponge + Dex group, epidural placement of collagen sponge in pure collagen sponge group, epidural placement of gelatin sponge in gelatin sponge group, and just directed suture in control group. Twelve weeks after operation, we observed the epidural scar formation and the dura adhesion. Application of immunohistochemistry and Western blotting analysis showed the expression of epidural scar and surrounding tissues in TGF-β1 and VEGF, and the differences between gelatin sponge group and control group were compared. Results Through macroscopic and microscopic observation, the epidural scar adhesion of collagen sponge + Dex group and pure collagen sponge group was obviously less than that in gelatin sponge group and the control group; while no significant difference was detected between collagen sponge + Dex group and pure collagen sponge group, and between gelatin sponge group and control group. Immunohistochemistry and Western blotting analysis showed the TGF-β1 and VEGF in epidural scar and surrounding tissues in collagen sponge + Dex group and pure collagen sponge group were significantly less than those of gelatin sponge group and control group; but no significance was detected between collagen sponge + Dex group and pure collagen sponge group and between gelatin sponge group and control group. Conclusion Collagen sponge could significantly reduce the formation of postoperative epidural scar adhesion in rats, while local injection of Dex could not enhance this effect; the local use of gelatin sponge could not reduce the formation of epidural scar adhesion. The expression of TGF-β1 and VEGF in the scar and surrounding tissue is significantly lower in the rats applied with collagen sponge, which should be an important mechanism for its prevention of epidural scars.