镁对缺氧缺血新生鼠脑保护作用的研究

目的 探讨镁离子对缺氧缺血性脑损伤（HIBD）的保护作用。方法 7日龄Wistar大鼠36史，随机分成3组，（1）假手术组，仅作颈正中切口，不作颈总动脉结扎；（2）对照组（生理盐水组）HIBD后即刻腹腔注射生理盐水0.5ml/只，每6小时1次，共6次；（3）观察组（硫酸镁组）HIBD后即刻腹腔注射硫酸镁450mg/kg，每6小时1次，共6次。（1）于手术后，（2）、（3）于最后1次用药后48小时断头取脑，分别测定脑组织中NO和MDA的水平，并作HE和Tunel染色，光镜下检测脑细胞凋亡数。结果 对照组大鼠脑组织中NO和MDA水平明显高于观察组，脑细胞凋亡数目两组比较差异有显著性意义。结论 镁离子对HIBD确有一定的保护作用，其可能的机理是拮抗兴奋性氨基酸NMDA受体，减少NO的合成，抑制自由基的活性，阻止脑细胞凋亡。

The study on the protective role of Magnesium on Hypoxic-ischemia brain damage in neonatal rats

Objective: To explore the protective role of magnesium(Mg) on Hypoxic ischemia Brain Damage(HIBD). Methods: Thirty-six 7-day old Wistar rats were divided into three groups, Sham, HIBD Nomal Saline(NS) (control) and HIBD Magnesium sulfate(MgSO4)(observe). Nitric oxide (NO) activities and malondialdehyde(MDA) level were measured in every rat brain for 48 h after the last use of the drugs, and the progressing death of brain cells was examined after being treated for 48 hours. Results:The NO activities and MDA level increased in HIBD NS, but decreased in HIBD MgSO4. The number of progressing death of the cells in HIBD MGSO4 was much lower than that in HIBD NS(P<0 05). Conclusion: Magnesium might be useful to protect brain tissue from hypoxic ischemia/reperfusion injury. Its machanism might lie in resisting NMDA, decreasing NO,inhabiting free radicals and cell apoptosis.