硫酸镁对改善实验性创伤性脑损伤后脑细胞线粒体呼吸功能作用的研究

目的 观察硫酸镁对创伤后大鼠脑线粒呼吸功能变化,并探讨可能作用机制,为临床进一步应用镁离子治疗创伤性损伤提供依据。方法 本实验采用BIM－Ⅲ型小型多功能生物撞击机造成大鼠中型颅脑损伤,用氧电极法分析线粒体呼吸功能（呼吸Ⅲ态,Ⅳ态和呼吸控制率）,并行透视电镜观察线粒体超微结构。结果（1）未治组伤后24、72小时呼吸Ⅲ态和呼吸控制率明显下降;治疗1组呼吸功能有所恢复;治疗2组呼吸控制率及呼吸Ⅲ态较治疗1组有显著升高（P＜0．05）,呼吸Ⅳ态稍有延长,但相差不显著。（2）电镜结果显示伤后未治组与治疗1组、治疗2组线粒体结构均有不同程度的损害,但应用Mg^2 治疗后线粒体损害程度减轻。结论 创伤性颅脑损伤后脑线粒体呼吸功能明显下降。应用硫酸镁治疗颅脑损伤大鼠可明显改善脑线粒体呼吸功能,形态学（电镜）观察也发现线粒体损害减轻。治疗时间延长,呼吸功能改善越明显。

Effects of magnesium sulfate on the brain mitoch ondrial respiratory function in experimental traumatic brain injury

Objective To study the effects of magnesium sulfate on brain mitochondrial respiratory function in rats after experimental traumatic brain injury and the possible mechanisms.Methods The middle degree brain injury in rats was made by BIM III multi function impacting machine. The brain cell mitochondrial respiratory function was measured with oxygen electrode and the ultrastructure changes were observed with transmission electron microscope.Results(1)?The brain mitochondrial respiratory functions reduced significantly in the untreated group within 24 and 72 hours. Treatment Group 1 showed certain degrees of attenuation. Treatment Group 2 showed further improvement.(2)?The ultrastructural characteristics in the control group remained normal, while the other three groups (untreated group , treatment group 1 and treatment group 2) had different degrees of mitochondrial ultrastructural damage, which could be attenuated after the treatment of magnesium sulfate.Conclusion The mitochondrial respiratory function decreased significantly after traumatic brain injury. Magnesium sulfate could improve the mitochondrial respiratory function in rats after traumatic injury. It could also attenuate the mitochondrial ultrastructural damage. The curative effect correlated with the course of treatment, i.e. the longer the course of treatment, the better the improvement of mitochondrial respiratory function.