猪胸腰段脊髓火器贯通伤后p53基因的早期表达

Early expression of p53 gene in pigs with gunshot injury in thoracolumbar spinal cord

目的:建立家猪胸腰段脊髓火器贯通伤模型和改良Allen's打击伤后全瘫模型,观察伤后促凋亡基因p53基因的早期表达。方法:实验于2005-05/08在解放军第一七五医院实验室完成。取健康雄性家猪20只,单纯随机分为3组:①火器伤组:9只,在全麻状态下制作胸腰段(L1～L2)脊髓火器伤模型,分为伤后1,3,6h3个时间处死。②打击伤组:9只,L1节段脊髓行改良Allen’s打击,致伤力为500g·cm,处死时间同前。③空白对照组:2只,只麻醉,不造模,伤后6h处死。伤后不同时间点(伤后1,3,6h)和不同节段(伤点、近伤点、中伤点及远伤点)取材,采用SP法进行P53蛋白免疫组化染色,用TJTY-300型全自动图像分析仪测量P53免疫组织化学染色阳性物质吸光度。结果:经补充后20只猪进入结果分析。①脊髓损伤后3h打击伤组伤点,火器伤组近伤段脊髓P53蛋白的表达高于空白对照组(P<0.001),随着时间推移,打击伤组和火器伤组P53蛋白的表达呈升高趋势(P<0.001),且火器伤组要高于打击伤组(P<0.0001)。②在脊髓损伤后6h,打击伤组仅在伤点和近伤段P53蛋白的表达高于空白对照组(5.57±0.82,3.21±0.43,P<0.05),而火器伤组近伤段、中伤段及远段伤均高于空白对照组(6.46±0.66,4.27±0.39,1.16±0.17,P<0.05)。结论:①细胞凋亡基因p53在脊髓损伤中的表达有一定的时空性,在脊髓损伤后3h出现P53蛋白表达量的增加。②脊髓火器伤的波及范围较打击伤更为广泛。

AIM：To create porcine models of gunshot spinal cord injury in thoracolumbar spine and complete paraplegia of contusion model with the modified Allen＇s method, and investigate the early expression of p53 gene as the apoptosis-promoting gene. METHODS： The experiment was conducted in the laboratory of the 175 Hospital of Chinese PLA from May to August 2005. Twenty healthy pigs were selected and randomly divided into three groups： ①gunshot injury group （n =9）： The models of thoracolumbar （LI-L2） spinal cord injury were established under general anesthesia, and the animals ware killed at 1, 3 and 6 hours after injury; ②Allen＇s method induced injury group （n =9）： The L1 segment spine underwent modified Allen＇s method stroke with 500 g .cm wounding power; the animals were killed at the same time point to the previous group; ③control group （n =2）： The pigs were only anesthetized without modeling, and killed at 6 hours after injury. Specimens ware obtained from different time points （1, 3, 6 hours after injury） and different segments （injury sites, proximal sites, middle sites and distal sites）; histological changes of these sites ware observed along with immunohistochemistry of P53, and the absorbance was detected with TJTY-300 automatic image analyzing system. RESULTS： Totally 20 pigs ware involved in the result analysis after supplement. ①The expression of proteins of P53 gene of injury sits after 3 hours injury in the Allen＇s method inducing injury group and the proximal sites of gunshot group ware higher than the control group （P 〈 0.001）; the expressions of the Allen＇s method inducing injury group and gunshot injury group ware increased with time （P 〈 0.001）, and the latter group was higher than the former one （P 〈 0.000 1 ）. ② After 6 hours injury, only the expressions in injury site and the proximal site of the Allen＇s method inducing injury group ware higher than the control group （5.57±0.82, 3.21±0.43, P 〈 0.05）, while the expressions in the injury site, middle and distal site of gunshot injury group ware all higher than the control group （6.46±0.66, 4.27±0.39, 1.16±0.17, P 〈 0.05）. CONCLUSION： ①The expressions of p53 protein in the spinal cord injury show a time and spatial characteristics, and the increase in P53 protein expression is found at 3 hours after injury. ②The injury area of gunshot injury is more extensive than that of the Allen＇s method induced injury.