N-3多聚不饱和脂肪酸抑制氧化应激途径对犬无菌性心包炎所致房颤的影响

N-3 polyunsaturated fatty acids prevents sterile pericarditis-induced atrial fibrillation by inhibiting oxidative stress in canine

目的采用犬无菌性心包炎模型检验n-3多聚不饱和脂肪酸（polyunsaturated fatty acids,PUFAs）对房颤的影响及其对心房内氧化应激状态的影响。方法 20只犬随机分为对照组和PUFAs组,分别行开胸造无菌性心包炎模型。PUFAs组实验开始前4周给予PUFAs 2g/d,术前和术后第2天分别测量心房各项电生理学指标（AF的诱导性和持续性指标、心房有效不应期、房内传导时间）,并采用蛋白质印迹法检测心房组织中3-硝基酪氨酸水平。结果术前两组间心房各项电生理学指标间差异无统计学意义。术后第2天与对照组相比,PUFAs组房颤可诱导性[（11.0±7.4）%vs（28.0±10.3）%,P〈0.001]和持续性[房颤时程中位数：1 105（655.8-1 406.5）s vs 2 516.5（1 187-3 361）s,P〈0.05]降低,并且心房有效不应期延长[（133.4±4.1）ms vs（129.8±4.3）ms,P〈0.05）],房内传导时间缩短[（46.6±4.4）ms vs（51.9±4.8）ms,P〈0.05],心房组织3-硝基酪氨酸水平降低（P〈0.000 1）。结论 PUFAs可以降低术后房颤的发生危险,其对氧化应激反应的抑制作用可能是其作用于房颤的机制之一。

Objective To study the anti-arrhythmic and anti-oxidative stress effects of n-3polyunsaturated fatty acids（PUFAs）in a canine sterile pericarditis model.Methods A total of 20 dogs were randomly assigned to two groups：a control group（10dogs）and a PUFAs treatment group（10dogs）,with sterile pericarditis created by open-chest operation in both groups.PUFAs was administered orally（2g/d）4weeks before the operation until the end of the study.The inducibility and maintenance of atrial fibrillation（AF）,atrial effective refractory period（AERPs）,and intra-atrial conduction time were determined before and 2days after the operation.And the level of 3-nitrotyrosine in the atrial tissue was determined by Western blotting analysis.Results The electrophysiology parameters were similar between the two groups.On day 2after operation,the PUFAs group compared with the control group had a significantly lower AF inducibility（[11.0±7.4]% vs[28.0±10.3]%,P〈0.001）and maintenance（median AF duration：1 105[655.8-1 406.5]s vs 2 516.5[1 187-3 361]s,P〈0.05）,a significantly longer AERP（[133.4±4.1]ms vs[129.8±4.3]ms,P〈0.05）,and a significantly shorter intra-atrialconduction time（[46.6±4.4]vs[51.9±4.8]ms,P〈0.05）.Western blotting analysis showed that 3-nitrotyrosine level in the atrial tissue of PUFAs group was significantly lower than that of the control group（P〈0.000 1）.Conclusion Dietary PUFAs supplementation can reduce the risk of AF after operation,and its anti-oxidative stress effect might be one of the mechanisms.