摘要
目的 观察小鼠脑内自由基及自由基清除系统在一氧化碳 (CO)中毒和高压氧治疗后的变化 ,L 硝基精氨酸甲酯 (L NAME)在CO中毒血 脑脊液屏障损伤中的作用 ,探讨这些变化与CO致脑损伤的关系。方法 分光光度计法分别测定各组小鼠脑内NO、NOS、MDA、SOD、GSH Px、CAT以及L NAME干预治疗的小鼠脑组织内伊文思蓝的含量。结果 ①中毒后NO含量和NOS活性降低 ,HBO使NOS活性明显恢复 ,有一定的NO恢复作用。②CO中毒后 ,MDA明显增多 ,SOD活性下降 ,HBO治疗抑制了MDA的增多 ,有助于SOD活性恢复 ;③GSH Px和CAT活性在CO中毒后增强 ,HBO使GSH Px活性进一步增强 ,而CAT活性回到基线 ;④CO使小鼠血 脑脊液屏障通透性增高 ,L NAME可减轻其损伤。结论 CO中毒后脑内氧自由基生成明显增多 ,HBO有助于减轻其损伤。三种抗氧化酶在CO中毒时出现的变化有利于清除自由基 ,而HBO推动了这一作用。CO中毒后早期应用NOS抑制剂可减轻对血 脑脊液屏障的损害 。
Objective To evaluate levels of free radicals(NO and MDA), NOS activity and radical eliminating enzymes (SOD and GSH-Px) with or without hyperbaric oxygen therapy after CO poisoning in mice brain; and effect of L-NAME on the damage of the blood-brain barrier caused by carbon-monoxide. Methods Mice were divided into different groups randomly (control, CO exposure, CO plus NBO therapy,CO plus HBO therapy). Brain samples were collected and a series of parameters were measured including NO,NOS,MDA, SOD, GSH-Px, and CAT. The changes of blood-brain barrier permeability were determined by detection of EB content with spectrophotometer.Results After CO poisoning , NO content and NOS activity decreased, MDA content increased and SOD activity decreased while activities of GSH-Px and CAT went up. After HBO therapy NOS activity recovered, and MDA producing was inhibited; GSH-Px continued to be upregulated, and CAT returned to baseline level. The permeability of blood-brain barrier was increased after acute carbon monoxide poisoning and the protection could be achieved by the application of L-NAME ( a NOS inhibitor)15 min before or 30 min after carbon monoxide exposure. Conclusion There are obvious changes of free radicals and process as lipid hyperoxidation happed after CO poisoning in mice brain. HBO therapy attenuates the injury. Enzymes of anti-oxygenation eliminate free radicals to some extent. HBO facilitates the process. The blood-brain barrier injury caused by CO poisoning may be partially mediated by NO, and L- NAME use could have clinical benefits.
出处
《中华急诊医学杂志》
CAS
CSCD
2004年第7期441-443,共3页
Chinese Journal of Emergency Medicine
