几丁聚糖对大鼠颈动脉球囊损伤术后血管内膜增生的影响

目的研究几丁聚糖对大鼠颈动脉球囊损伤术后再狭窄的影响,并探讨其机制。方法60只SD大鼠分为几丁聚糖组和模型组各30只。复制大鼠颈动脉球囊损伤模型。几丁聚糖组在术前1周即开始每天一次灌胃几丁聚糖2g,并在术后继续给予至处死;模型组只建立模型但不予以任何处理。分别于手术后即刻(0d)、7d、14d、28d和35d,每组各处死大鼠6只。光镜下观察血管内膜损伤;运用图形分析系统检测增殖的内膜面积;α肌动蛋白免疫组织化学检测增殖内膜细胞的性质,血管内皮生长因子免疫组织化学标记血管内皮细胞明确损伤后血管内皮修复情况。结果模型复制成功53例,几丁聚糖组28例,模型组25例。手术后即刻见血管内膜完全剥脱,部分可见平滑肌细胞断裂。手术后7d可见内膜增生。模型组血管内膜在第28天增生达高峰,几丁聚糖组内膜增生在术后14d达到高峰。几丁聚糖组与模型组比较内膜增生程度差异有显著性(P均<0.05)。α肌动蛋白检测结果显示增殖的内膜细胞为血管平滑肌细胞。血管内皮生长因子检测结果显示几丁聚糖组在手术后14d血管完全再内皮化,而模型组手术后28d才完全再内皮化。结论几丁聚糖能预防大鼠颈动脉球囊损伤术后再狭窄,其机制可能与几丁聚糖促进血管再内皮化有关。

The Effect of Chitosan on the Endothelial Regeneration and Neointimal Proliferation After Arterial Balloon Angioplasty in Rat

Aim To investigate the effect of chitosan on the endothelial regeneration and neointimal proliferation after balloon angioplasty of right carotid artery in rat. Methods Endothelial denudation of artery in rat were performed with 2F balloon catheter. 50 SD rats were randomly divided into the modle group and the chitosan group. Artery were harvested on 0 d, 7 d, 14 d, 28 d and 35 d after the injury, respectively. The reendothelialization and the neointimal hyperplasia were observed cross-sections stained with hematoxylin-eosin from the injured segments processed for histological and morphological study by computer-assisted picture analysis system. Results Chitosan enhanced the reendothelialization of the injured arterial determined vascular endothelial growth factor (VEGF) staining. The absolute reendothelialization was observed on 14 d in chitosan group but on 28 d in the modle group. Intimal hyperplasia and lumen stenosis can be seen on the 7 d after injury. At the 28th day the intimal thicken reached at a peak. In the chitosan group the intimal thicken reached at a peak at the 14 th day. There were significant difference of neointimal in the chitosan group and the modle group on the 14th day, 28th day and 35th day. Conclusions Chitosan is effective on intimal hyperplasia and lumen stenosis after arterial injury by inhibiting neointimal proliferation which is related to the reendothelialiazation.