一氧化碳中毒和高压氧治疗前后大鼠脑一氧化氮和一氧化氮合酶活性的变化

目的：观察急性一氧化碳（ＣＯ）中毒大鼠脑组织中一氧化氮（ＮＯ）、一氧化氮合酶（ＮＯＳ）活性的变化及高压氧（ＨＢＯ）对其的影响。方法：建立实验性大鼠ＣＯ中毒模型，采用改良的Ｇｒｉｅｓｓ法、分光光度法分别测定一氧化碳中毒及高压氧或常压氧治疗后大脑和小脑中ＮＯ、ＮＯＳ活性。结果：ＣＯ中毒后小脑ＮＯ明显增加，ＮＯＳ活性受抑制。ＨＢＯ治疗使ＮＯ、ＮＯＳ均恢复到正常水平。ＣＯ中毒后大脑ＮＯ降低，ＮＯＳ活性受抑制。ＨＢＯ治疗使ＮＯ增高，ＮＯＳ活性恢复正常。结论：急性ＣＯ中毒使大脑及小脑ＮＯ、ＮＯＳ活性均发生改变，这种改变可能参与ＣＯ造成的脑损伤。ＨＢＯ治疗有益于对脑ＮＯ、ＮＯＳ变化的调节作用。

Changes of Nitric Oxide Production and Nitric Oxide Synthase Activities in Brain after Carbon Monoxide Poisoning in Rats

Objective:The purpose of this study was to evaluate levels of nitric oxide (NO) and nitric oxide synthase (NOS) in rat brain after exposure to carbon monoxide with or without hyperbaric oxygen (HBO) therapy. Methods: Eighty male Wistar rats were randomly divided into 5 groups. The rats were killed after different therapies. Cerebellum as well as cerebrum were seperated. NO levels were measured by Griess' medthod, and NOS activity was measured by spectrophotometry. NO and NOS levels were compared among the 5 groups. Results were analyzed using one way analysis of variance (ANOVA) following q test.Results: In the rat cerebellum, the level of NO increased and the level of NOS decreased after CO exposure. The level of NO decrased after HBO therapy, but not NBO therapy. NBO and HBO both resulted in a retum of NOS levels to baseline. In rat cerebrum, NO and NOS decreased after CO exposure. The NO level increased after HBO therapy but not after NBO therapy Both NBO and HBO increased NOS activity. Conclusion: The demonstrated changes in levels of NO and NOS may play an important role in the neurologic damage resulting from CO poisoning. HBO exerted significant effects on NO production and NOS activity in cerebellum and cerebrum after CO exposure in rats.