大鼠皮肤切创后E-选择素表达及稳定性研究

目的探讨大鼠皮肤切创后E-选择素表达规律及法医学意义。方法健康SD大鼠90只，随机分成4组：正常对照组、活体切创组（30min～7d12个时间点）、死后切创组（30min～3h3个时间点）、死后稳定性组（-20％6h-7d9个时间点，25％6h～3d5个时间点）。在大鼠头部建立皮肤切创模型，按设定的时间点取皮肤检材，运用免疫组化和图像分析技术，检测血管内皮E-选择素的表达规律。结果在活体切创组中，伤后1hE-选择素在血管内皮细胞内即呈阳性表达，持续至伤后7d，且随时间变化呈规律性表达。在正常对照及死后切创组未见阳性表达。死后-20％稳定性组各时间点E-选择素表达与死后即刻比较无显著性差异（P〉0．05）。25％各时间点与死后即刻比较有显著性差异（P〈0．01）。结论E-选择素在创伤后血管内皮细胞内特异性的表达具有时序性规律，且低温条件下稳定性较好。

A study on expression of E-selectin in the incised skin wound and its stability in rats

】Objective To study the expression of E-selectin in incised skin wound in rats and its significance in forensic medicine.Methods 90 healthy SD rats were randomly divided into 4 groups: normal control group;antemortem incised group(30min～7d,12 post-incision intervals);postmortem incised group(30min～3h,3 postmortem intervals);postmortem stability groups(1d incised skin wound preserved at-20℃ and sampled at 6h～9d postmortem,9 postmortem intervals and 1d incised skin wound preserved at 25℃ and sampled at 6h～3d,5 postmortem intervals).Incised skin wound was made on the top of the head in the rat.Detection of E-selectin was conducted by immunohistochemical technique.Image analysis were used to study the dynamic expression of E-selectin in the skin vascular endothelial cells.Results In antemortem incised group,the positive immunoreactivity of E-selectin was detected as early as 1h and lasted till 7d after incision in the vascular endothelial cells and changed time-dependently with the extension of post-incision interval.No positive immunoreactivity of E-selectin in the control skin and post-mortem incised skin wound.There was no significant difference in E-selectin expression among each postmortem stability group of which skin samples were kept at-20℃ as compared with the wounded skin at 0h after injury(P>0.05).However,there was significant difference in E-selectin expression among each postmortem stability group of which skin samples were kept at 25℃ degree as compared with the wounded skin at 0h after injury(P<0.01).Conclusion E-selectin is time-dependently expressed in the vascular endothelial cells with the extension of post-incision interval,and is of stability under the condition at lower temperature.