犬颅脑爆震伤后脑组织中NO、ET变化实验研究

Changes of NO and ET content in brain tissues after craniocerebral explosive injury in dogs

目的建立不同伤情颅脑爆震伤动物模型,探讨颅脑爆震伤后脑组织中细胞因子一氧化氮(NO)、内毒素(ET)的变化。方法杂种雄性犬30只,随机分为:轻伤I组(13 mm,n=10),中度伤II组(9 mm,n=10)及重伤III组(5 mm,n=10),用1 g TNT当量的球型爆炸源置于距右颞顶部不同距离(13 mm、9 mm、5 mm)对犬的颅脑部引爆致伤,制作轻、中、重型颅脑爆震伤动物模型,伤后1 h、3h、6 h、12 h检测脑组织中NO、ET含量。结果犬爆震伤后,各组脑组织中NO含量与伤前比较明显升高(P<0.01),6 h达到峰值。在相同的时间点轻、中、重型伤NO含量之间有显著性差异(P<0.05)。各组脑组织ET含量与受伤前相比显著升高(P<0.01),随时间延长逐渐升高,在相同的时间点III组ET含量均较I组有显著性差异(P<0.05)。结论颅脑爆震伤后脑组织中NO、ET有不同程度的升高,伤情越重,数值指标越高,提示NO和ET可能在颅脑创伤早期的疾病演进中发挥作用。

Objective To establish dog model of craniocerebral explosive injury with different degree and observe the changes of NO and ET content in brain tissues after craniocerebral explosive injury.Methods Thirty mongrel male dogs were randomly divided into slight injury group I（13 mm,n=10）,moderate injury group II（9 mm,n=10） and severe injury group III（5 mm,n=10）.A spherical explosive with explosive energy of 1g TNT was used to detonate at different distances（13 mm,9 mm,5 mm） from dogs＇ heads to cause the slight,moderate,and severe craniocerebral explosive injury,respectively.The changes of NO and ET content in brain tissues were observed in each group at 1 h,3 h,6 h,12 h post-explosion.Results The NO content following cerebral explosive injury was increased significantly compared with that of pre-injury（P0.01）,and peaked at 6 h post-injury.The NO content at the same time point in different groups was significantly different（P0.05）.The ET content following explosive injury was increased in a time-dependent manner and was significantly higher compared with that of pre-injury.There was significant difference in ET content at the same time point between group III and group I（P0.05）.Conclusion The contents of NO and ET in brain tissues of dogs areincreased in various degree following craniocerebral explosive injury and have positive correlation with the severity of injury,which suggests that NO and ET may play an important role in the early progression of traumatic brain injury.