异丙酚对大鼠脑弥漫性轴索损伤后的脑保护作用

Protective effects of propofol in diffuse axonal injury in rats

目的 评价异丙酚对损伤后脑组织的神经保护作用。方法 取健康Wistar大鼠 72只 ,采用Marmarou弥漫性颅脑损伤动物模型制备方法 ,造成大鼠重度颅脑损伤。异丙酚组 (P组 )给予1%异丙酚 1mg·kg-1·min-1持续静注 3h ;对照组 (C组 )伤后不作处理 ;正常组 (N组 )不造成颅脑损伤。各组在伤后 6、2 4、48和 72h分别取脑组织做电镜观察和血生化指标测定。结果 (1)形态学 :C组各时相显示了典型DAI改变过程 ;P组在 48和 72h轴索改变、微血管及胶质细胞损伤程度均明显轻于C组 ;(2 )血生化指标 :损伤后NES、ET和MDA值P组和C组均较N组明显升高。但P组升高程度明显低于C组 ,并且随时间延长P组各值逐渐下降 ,而C组仍持续在较高水平。MBP与NO在损伤组 (P组与C组 )升高较迟缓 ,于 72h达到高峰。MBP升高程度P组明显低于C组 ,而NO改变两组间无显著差异 ;(3)脑组织含水量 :损伤后C组持续高于正常水平 ,而P组显著低于C组 ,并且在 48h和72h恢复到N组水平。结论 本实验证实了异丙酚的脑组织保护作用。

Objective To evaluate protective effects of propofol administered after diffuse axonal injury (DAI) Methods According to Marmarou′s methods, a closed brain injury animal model was established to create severe diffuse head injury in Wistar rats Animals were divided into 3 groups In propofol group 1% propofol was infused intravenously at 1mg·kg -1 ·min -1 for 3 h, 30 min after head injury ( group P n=28) In control group no treatment was given (group C n=28) 8 rats without head injury were used as normal control (group N n=8) Brain tissue and blood samples were taken at 6, 24, 48 and 72 h after head injury for electromicroscopic examination and measurement of levels of serum myelin basic protein (MBP), neuron specific enolase(NSE) nitric oxide (NO) and malondialdebyde (MDA), and plasma endothelin (ET) Results The typical morphological changes of DAI were shown in group C; There were less axonal, gliocyte and microvascular injuries at 48 and 72 h after injury in group P than in group C The levels of serum NSE and MDA and plasma ET increased significantly after head injury in group C and P as compared with those in group N, but the increase in group P was less than in group C MBP and NO increased gradually and peaked at 72h after injury in group P and C The increase in MBP was less in group P than that in group C but no significant difference in NO was seen between the two groups Brain tissue contained more water in group C than in group P The water content returned to normal level at 48h and 72h after injury in group P Conclusions The study comfirms that propofol affords neuroprotection in rat DAI model Key Words Propofol; Neuroprotective agents; Brain injuries were greatly lower in analgesia group than those in control group 3d after operation(P<0 01) Compared with the baselines, all values remained stable 3d after operation(P>0 05), RCR increased markedly 7d after operation(P<0 01)in analgesia group; in control group RCR,RFER and NTERT decreased significantly , RICR and RFIR increased obviously 3d after operation(P<0 05 or 0 01), all values recovered(P>0 05) Conclusions Postoperative analgesia can help stabilize erythrocyte immunity function