高速胸部撞击伤家兔中性粒细胞凋亡与肺损伤

Apoptosis of polymorphonuclear neutrophil and lung injury in rabbits following chest injury by high-velocity impact

目的:观察兔胸部高速撞击伤后中性粒细胞凋亡的发生与肺损伤的关系。方法:样品采集与处理于2003-05/2004-12,分别在解放军第四军医大学西京医院心脏外科实验室和胸部战创伤基础理论与临床实验室完成。实验选用健康国内本土兔30只,随机分为对照组5只,实验组25只。实验组动物应用呼吸心跳同步触发撞击机致伤右侧胸壁,压缩幅度20%,撞击质量5.7kg,撞击面积3.14cm2,弹丸速度(20.29±0.03)m/s。对照组不做撞击伤,其余处理同实验组。实验组于伤后4,12,24,48和72h分别处死动物5只(伤后4,12,24,48,72h组),留取支气管肺泡灌洗液及肺组织,应用膜连蛋白V-异硫氰基荧光素及碘化丙啶染色、流式细胞仪检测中性粒细胞凋亡,应用考马氏亮兰法、比色法测定总蛋白和白蛋白含量,肺组织苏木精-伊红染色及测定肺干湿重比值。结果:①伤后4,12,24,48,72h实验组支气管肺泡灌洗液凋亡的中性粒细胞比例明显低于对照组(63.1±7.6)%,(62.5±9.5)%,(64.2±7.1)%,(63.6±7.7)%,(61.5±8.5)%;(82.3±12.6)%,t=2.80～3.06,P<0.05。②伤后4,12,24,48,72h实验组肺干湿重比值明显低于对照组(0.32±0.10,0.29±0.03,0.26±0.05,0.25±0.01,0.21±0.03;0.48±0.07,t=2.90～7.94,P<0.05～0.01);伤后12,24,48。

AIM:To investigate the relationship between apoptosis impacted of polymorphonu clear neutrophil(PMN) and lung injuries following chest injuries by high veloci ty impact in rabbits. METHODS:Samples for the study was collected and treated respectively in the la boratory of Cardiac Surgery,laboratory for Basic Theory and Clinic of Thoracic W ar Trauma,Xijing Hospital,Fourth Military Medical University of Chinese PLA from May 2003 to December 2004.Thirty healthy Chinese rabbits were randomly assigned to control group(n=5) and experimental group(n=25).The rabbits in experimental group were struck on the right thoracic wall by synchronous cardiorespiratory t riggered impactor with compression of 20%,strike mass of 5.7 kg,and strike area of 3.14 cm2 at(20.29±0.03) m/s.The rabbits in the control group underwent simi lar interventions but not being struck.At 4,12,24,48 and 72 hours after wound,ra ndom 5 rabbits in experimental group were killed respectively as 4 hour group,1 2 hour group,24 hour group,48 hour group and 72 hour group.Bronchoalveolar l avage fluid(GALF) and lung were sampled to evaluate the apoptosis of PMN with An nexin V fluorescein isothiocyanate(V FITC),propidium iodide(PI) staining and f low cytometry.Chromatometry and Coomassie brilliant blue were employed to determ ine level of total protein and albumin.The lung tissue was stained with hematoxy lin and eosin(HE). The ratio of dry to wet lung weight was measured. RESULTS:①In the 4 hour,12 hour,24 hour,48 hour and 72 hour groups,the ra te of apoptotic PMN in BALF decreased significantly after injury,as compared wit h control group[(63.1±7.6)%,(62.5±9.5)%,(64.2±7.1)%,(63.6±7.7)%,(61.5±8 .5)%vs(82.3±12.6)%,t=2.80 to 3.06,P< 0.05].②The ratio of dry to wet lung wei ght significantly declined after injury in all the experimental groups as compar ed with that of control group(0.32±0.10,0.29±0.03,0.26±0.05,0.25±0.01 and 0. 21±0.03 vs 0.48±0.07,t=2.90 to 7.94,P< 0.05 to 0.01).The index of lung pulmona ry permeability significantly increased in 12 hour,24 hour,48 hour and 72 ho ur groups,compared with the control group(1.1±0.3,1.4±0.2,1.5±0.4 and 1.7±0. 6 vs 0.6±0.2,t=3.13 to 6.35,P< 0.05 to 0.01). CONCLUSION:The depression of PMN apoptosis is correlated with more and more se vere respiratory damages secondary to lung injury.