硫酸镁对脑外伤兔超氧化物歧化酶影响的动态观察

目的　探讨硫酸镁对脑外伤兔血中超氧化物歧化酶 (SOD)的动态影响。方法　新西兰大白兔 4 0只 ,随机分为对照组和硫酸镁组 ,采用改良Feeney自由落体脑损伤装置制造重型脑外伤模型 ,脑外伤后 30分钟 ,对照组给予 2 0 %甘露醇 10 0ml及生理盐水 5 0 0ml静滴 ,1次 /日。硫酸镁组则在滴注 2 0 %甘露醇 10 0ml后给予硫酸镁针 0 5g(2 5 %硫酸镁针 2 0ml)加入 5 0 0ml生理盐水中静滴 ,1次 /日 ,连续 5天。两组分别于伤前(0h)及伤后 3h、12h、2 4h、4 8h、72h、96h、12 0h静脉抽取血液标本 2ml,用分光光度计进行血浆SOD检测。结果　对照组和治疗组比较F =2 9 38,P <0 0 0 1,表明两组之间SOD的差别有统计学意义 ;不同时间的SOD的差别具有统计学意义 (P <0 0 0 1) ;组别与时间之间存在差别交互作用 (P <0 0 0 1)。结论　硫酸镁在脑外伤后早期(5天内 ) ,通过抑制SOD降低 ,阻止自由基大量生成而起脑保护作用并降低重型脑外伤的死亡率。

An Experimental study of Magnesium Sulfato on Plasma SOD Dynamic Influence in Rabbit Brain Injury

Objective To study the protective action of magnesium sulfate to the brain and the dynamic effect on blood superoxide dismutase(SOD)in cerebral trauma rabbits,and to provide the theory foundation in treatment and guiding drug administration.Methods 40 New Zealand adult rabbits were randomly divided into 2 groups:control group (n=20) and treatment group (n=20).Severe brain trauma was made by modified Feeney free dropping mode.Thirty minutes later of cerebral trauma,the rabbits in control group were treated with 20% mannitol 100ml and normal saline 500ml iv.gtt.qd.and the rabbits in treatment group were treated with above same method plus magnesium sulfate 0.5g added in normal saline 500ml iv.gtt.qd.All rabbits in two groups were treated with above method for five consecutive days.Before and after brain trauma 3h,12h,24h,48h,72h,96h,120h,all rabbits were drawn 2ml blood from groin vein or external jugular vein.722 spectrophotometer was used to measure plasma SOD.Results According to analysis of variance,between control group and treatment group F=29.38,P<0.001.It indicated that the difference of SOD between two groups has statistic significance; the difference of SOD on various time points had statistic significance (P<0.001).The groups and time have interaction (P<0.001).Conclusions Magnesium sulfate plays a role in protecting brain and reducing the mortality of brain trauma by inhibiting SOD descend and reducing free radical production within five days after trauma.