大鼠液压冲击脑损伤脑组织Toll样受体4表达与神经功能的关系

目的 观察大鼠液压冲击脑损伤Toll样受体4（TLR4）表达变化,探讨其与神经功能的关系.方法 成年雄性SD大鼠56只,随机分为损伤组（n=48）和假手术组（n=8）.采用液压冲击制备颅脑损伤模型,术后1h、6h、12h、24 h、3d、7d对动物进行神经功能评分,并用干湿重法、免疫组化法和Western Blot 分别测定水肿脑组织含水量及TLR4蛋白表达.结果 神经功能评分6h出现下降（3.86±0.42）分],24 h下降至最低值（2.65±0.32）分],3d逐渐升高（3.25±0.17）分];免疫组化和Western Blot均显示水肿脑组织TLR4的表达均6h开始增高,24h至3d达到高峰,7d后降低.线性相关性分析发现TLR4表达与神经功能评分呈显著负相关（r1=-0.824,rw=-0.867,P＜0.05）.结论 大鼠颅脑液压冲击伤TLR4出现高表达,可能诱发了继发性炎性脑损伤导致神经功能障碍.

The relationship between the expression of Toll-like receptor 4 and neurological function after fluid percussion brain injury in rats

Objective To investigate the expression of Toll-like receptor 4 （TLR4）,and explore its relationship with neurological function after fluid percussion brain injury in rats.Methods 56 adult rats were randomly divided into traumatic brain injury group（TBI group,n=48） and sham operation group（SO group,n=8）.The experimental models were established.The water content of edematous brain and the expression of TLR4 were measured with dry-wet measure,immunohistochemistry and Western Blot at 1 h,6 h,12 h,24 h,3 d,7 d after shock respectively.Results Compared with SO group,neuronal function score decreased in TBI group from 6 h（3.86±0.42）,reached to the lowest level at 24 h（2.65±0.32）,and gradually rose at 3rd day （3.25±0.17）.TLR4 immunoreactive expression increased from 6 h,reached its maxmum at 24 h,lasted to 3rd day,and then began to drop at 7th day.The linear regression analysis indicated that expression of TLR4 had negative correlation with change of neuronal function score （r 1 =-0.824,r w =-0.867,P〈0.05）.Conclusion TLR4 expression is upregulated following fluid percussion injury in rats and involved in neurological function impairment by inducing secondary inflammatory brain injury.