地塞米松冲击疗法对犬抗氧化及免疫功能的影响

Effects of dexamethasone pulse therapy on antioxidation and immune function in dogs

目的:研究临床地塞米松冲击疗法对犬抗氧化及免疫功能的影响。方法:选取8只健康成年犬,连续肌肉注射地塞米松(2 mg/kg·BW)4 d后恢复2 d,每天采集静脉血液,测定血清中氧化还原指标以及免疫相关指标。结果:与试验前相比,肌注地塞米松1 d血清总抗氧化能力显著升高(P<0.05);第1~4天及恢复期第1天血清超氧化物歧化酶活性显著降低(P<0.05);第3天血清过氧化氢酶活性显著降低(P<0.05);第1~3天及恢复期第1天血清巯基含量显著升高(P<0.05),恢复期第2天恢复正常;第1~4天血清维生素E含量显著升高(P<0.05),恢复期恢复正常;第1、3~4天以及恢复期1~2 d血清总羰基含量显著升高(P<0.05);第3~4天血清一氧化氮(NO)含量显著升高(P<0.05),恢复期降至正常水平;肌注地塞米松第3~4天时血清免疫球蛋白M(IgM)、免疫球蛋白G(IgG)、免疫球蛋白A(IgA)以及C-反应蛋白(CRP)含量显著降低(P<0.05)。结论:地塞米松改变犬机体的氧化应激状态,免疫功能显著降低,临床上应用地塞米松冲击治疗时应及时纠正氧化还原状态和调节免疫水平。

Objective:This experiment was conducted to investigate the effects of dexamethasone pulse therapy on the antioxidation parameters and immune function of serum in dogs.Methods:A total of eight healthy adult dogs were selected for clinical examination.After 4 d of continuous intramuscular injection of dexamethasone(2 mg/kg body weight),dogs were recovered after 2 days.Blood was collected from the vein on a daily basis to determine the activity or content of redox indicators and immune-related indicators in the serum.Results:The total antioxidant capacity in blood serum was significantly increased after intramuscular injection of dexamethasone for 1 day(P<0.05).The activity of superoxide dismutase was significantly decreased on the 1st to 4th day and the 1st day of recovery period(P<0.05).The activity of catalase was decreased significantly on the 3rd day(P<0.05).The content of sulfhydryl was increased significantly on the 1st to 3rd day and the 1st day of recovery period(P<0.05),and returned to normal at the 2nd day of recovery period.Vitamin E was increased significantly at 1-4 days(P<0.05)and returned to normal at the recovery stage.The total carbonyl content was increased significantly at the 1st and 3rd to 4th day and at the 1st to 2nd day of recovery(P<0.05).The content of nitric oxide was increased significantly at 3-4 days(P<0.05),and decreased to the normal level during the recovery period.The contents of immunoglobulin M,immunoglobulin G,immunoglobulin A and C-reactive protein were significantly decreased after intramuscular injection of dexamethasone for 3-4 days(P<0.05).Conclusion:Dexamethasone changed the oxidative stress state in the dog and significantly reduced the immune function.In clinical use,dexamethasone pulse therapy could timely correct the redox state and regulate immune levels.