右甲吗喃对大鼠脑损伤后血脑屏障保护作用的实验研究

The protective effect of dextromethorphan on bloodbrain barrier following traumatic brain injury in rats

目的：研究Ｎ甲基Ｄ门冬氨酸（ＮＭＤＡ）受体非竞争性拮抗剂——右甲吗喃对大鼠脑创伤后血脑屏障的保护作用。方法：利用伊文思蓝（ＥＢ）只透过血脑屏障的特点，于大鼠脑损伤前３０分钟及伤后１０分钟、２小时腹腔内注射右甲吗喃（１０ｍｇ／ｋｇ），伤后６小时测定脑半球ＥＢ含量并进行统计学分析。结果：伤前３０分钟及伤后１０分钟应用右甲吗喃可显著降低伤侧脑半球ＥＢ含量（Ｐ均＜０．０１），伤后２小时用药与生理盐水对照组比较无显著性差异（Ｐ＞０．０５）；伤前３０分钟与伤后１０分钟、伤后１０分钟与伤后２小时用药比较均有非常显著性差异（Ｐ均＜０．０１）。结论：脑损伤后２小时以前应用右甲吗喃对血脑屏障损伤具有防治作用。

Objective:To observe the protective effect of noncompetitive NmethylDaspartate receptor antagonist——dextromethorphan (DM) on bloodbrain barrier following traumatic brain injury in rats.Methods:Male Wistar rats were divided into 4 groups according to DMtreated intervals:30 minutes preinjury (group A,10 mg/kg i.p.),10 minutes postinjury (group B),2 hours postinjury (group C),and saline controls.Rats were sacrificed at 6 hours after injury,and the content of Evans blue was measured in the hemisphere.Change in bloodbrain barrier was determined by the Evans blue method.Results:Compared with control group,Evans blue contents were significantly reduced in both group A ( P <0 01) and group B( P <0 01). Significant differences in Evans blue content were observed between group A and B,group B and C respectively (both P <0 01),while no marked changes were found between controls and group C( P >0 05).Conclusions:Early use of DM may have beneficial effect on blood brain barrier disruption following traumatic brain injury in rats.