动脉修复过程中组织结构成分与生物力学指标的变化规律

Change law of structure component and biomechanical index during repair of anastomotic artery

目的:探讨动脉吻合后的修复过程中,动脉壁弹性纤维和胶原纤维结构成分及吻合口段动脉顺应性的变化规律。方法:实验于2005-03/2005-06在解放军第三军医大学完成。选用健康成年Wistar大鼠50只,雌雄不拘,体质量195～230g。随机分为动脉吻合术后3,7,14,30d组和正常对照组,每组10只。动脉吻合手术组麻醉后,显露游离股动脉中部,切断后以12/0尼龙线行端端吻合。正常对照组只显露股动脉不行动脉切断及吻合术。在体测定大鼠股动脉吻合后3,7,14,30d吻合口段的压力与直径相关数据,分析动脉的顺应性与平均血压的关系。取术后各时间点的动脉段,常规石蜡切片后,分别行弹性纤维和胶原纤维特殊染色,显微图像分析测定两种纤维结构成分的相对含量;同时采用寡核苷酸探针组织切片原位杂交,检测各时间点动脉壁弹性蛋白原mRNA表达变化。结果:实验大鼠50只均进入结果分析。①与正常对照组相比较,术后3～14d吻合口段动脉的顺应性逐渐降低,术后14d降低最显著。术后30d有所回升。②术后3～7d弹性纤维和胶原纤维相对含量与对照组比较无显著变化,术后14和30d弹性纤维和胶原纤维相对含量高于对照组[弹性纤维:(0.269±0.039),(0.350±0.062);胶原纤维:(0.684±0.031),(0.691±0.023);对照组:(0.189±0.035),(0.294±0.047),P<0.05]。③术后14d胶原纤维与弹性纤维含量的比值较对照组明显增高(4.20±0.56,1.66±0.39,P<0.05)。④术后3d动脉壁即有弹性蛋白原mRNA的表达,术后7d为表达高峰期,随后表达逐渐减少。结论:动脉吻合后的修复过程中其可扩张能力呈先减弱后有所回升的变化趋势,这种生物力学特性变化与动脉组织结构成分改变密切相关。

AIM： To explore the changes of contents of elastic fiber and collagen fiber, and biomechanical property of anastomotic arteries during repair process. METHODS： The experiment was conducted at the Third Military Medical University of Chinese PLA between March and June 2005. Fifty healthy adult Wistar rats （male and female） were selected with the body mass of 195-230 g. They were assigned randomly into 3, 7, 14 and 30 days artery anastomosis groups and normal control group with 10 rats in each group. After anesthesia, the middle freeing femoral arteries of rats in the artery anastomosis group were exposed. After cutting, end-to-end anastomosis was performed with 12/0 nylon thread. Only femoral- artery was exposed, but did not perform the artery break and anastomosis in the normal control group. The related data of arterial pressure and diameter were measured 3 days, 7 days, 14 days, and 30 days after anastomosis in rat femoral arteries. The arterial compliance was calculated, and the relationship between compliance and average pressure was determined. The anastomosed arteries were removed at each time point, paraffine and stained with various methods of elastic fiber and collagen fibers. The relative contents of elastic fiber and collagen fiber in arterial wall were measured with image analysis system. The change of expression of tropoelastin mRNA was observed by oligonucleotides in situ hybridization technology. RESULTS： A total of 50 experimental rats were involved in the result analysis. ①Compared with the normal control group, the compliance of arteries gradually decreased from 3 days to 14 days after anastomosis, It was decreased most markedly at 14 days, and partially returned at 30 days after anastomosis. ②The contents of elastic fiber and collagen fiber from 3 days to 7 days had no significant difference, and it increased at 14 days and 30 days after operation than that in the control group [elastic fiber： （0.269±0.039）, （0.350±0.062）; collagen fibers： （0.684±0.031 ）, （0.691 ± 0.023）; control group： （0.189±0.035）, （0.294±0.047） ,P 〈 0.05]. ③The ratio of contents of collagen fibers and elastic fibers increased significantly after operation for 14 day than that in the control group （4.20±0.56,1.66± 0.39,P 〈 0.05）. ④There was expression of tropoelastin mRNA after 3 days of anastomosis. The peak expression was noted at 7 days after anastomoses and decreased gradually. CONCLUSION： The distensibility of anastomotic artery decreases in earlier period after operation, and then returns partially during repair process. The biomechanical property change is closely related to the changes of the contents of structural components in arterial tissue.