褪黑素对烫伤大鼠脑组织抗氧化能力与星形胶质细胞的影响

Effect of Melatonin on oxidative stress and astrocyte in brain tissue of burns modal rats

目的观察褪黑素(melatonin,MT)对烫伤大鼠脑组织GSH、SOD与MDA含量与星形胶质细胞的影响,以探讨烫伤后MT的神经保护机制。方法随机将30只SD大鼠,分为正常对照组、烫伤组和MT治疗组;MT治疗组在烫伤后10 min,3 h分别给予MT(10 mg/kg)腹腔注射治疗,对照组与烫伤组给予等量体积的生理盐水。MT治疗结束后1 h取脑行GSH、SOD与MDA含量检测,然后取额叶皮质行GFAP免疫组化染色,光镜下观察星形胶质细胞的形态变化并进行计量分析。结果与正常对照组相比,烫伤组大鼠脑组织GSH含量下降,而SOD与MDA含量增加,GFAP阳性神经元增多(P<0.05)。与烫伤组相比,MT治疗组大鼠脑组织GSH含量增加,SOD与MDA含量下降,GFAP阳性神经元减少(P<0.05)。结论烫伤后早期应用MT治疗,可以改善机体的氧化应激水平和神经系统的继发性损伤。

Objective To investigate the mechanism underlying the effects of Melatonin（MT）on burns vulnerated by steam,and study the changes of Glutathione,Malonaldehyde and Superoxide dismutase contents and astrocyte in rat cortex of frontal lobe.Methods The thirty mature Sprague-Dawley rats were randomly divided into the normal control group,the steam injury group and Melatonin treatment group.Melatonin（10 mg/kg.d）was injection into the abdominal cavity after 10 min and three hours in the Melatonin treatment group,and an identical volume saline were given for both the steam injury model group and the normal control group.After treatment one hour,GSH,SOD and MDA were measured,Frontal cortex were carried out GFAP immunopositive neurons.The change of form of astrocyte were analyzed by microscopit.Results Glutathione content of the steam injury group were significantly descented than the normal control group,but the Malonaldehyde and Superoxide dismutase contents were increased（P〈0.05）.Meanwhile,GFAP immunopositive neurons were significantly decreased were decreased（P〈0.05）.The Malonaldehyde and Superoxide dismutase contents were descented in the steam injury group,while,the Glutathione and GFAP immunopositive neurons were significantly increased（P〈0.05）.Conclusion Early melatonin cure after burns may attenuate oxidative damage,reduce inflammation and protect the brain cells.