左旋卡尼汀在犬心房急性电重构中的抗氧化作用  

Anti-oxidative stress effects of L-carnitine on acute atrial electrical remodeling in dogs

作　　者：官媛[1,2] 单兆亮[1] 郑强荪[2] 张晔[1] 郭红阳[1] 王玉堂[1] 

机构地区：[1]解放军总医院心内科,北京100843 [2]第四军医大学唐都医院心内科,陕西西安710038

出　　处：《心脏杂志》2011年第1期7-10,共4页Chinese Heart Journal

基　　金：国家自然科学基金项目资助(30772886)

摘　　要：目的:探讨左旋卡尼汀(L-carnitine,L-CN)抑制犬心房颤动(房颤)时心房急性电重构的作用机制。方法:18条成年杂种犬,随机分为生理盐水(NS)组、L-CN组和正常对照(normal control,NC)组。NS组予右心房600次/min快速起搏,诱发并维持房颤2 h;起搏前半小时静推生理盐水(300 mg/kg),继以液速50 ml/h维持静脉点滴2 h。L-CN组:右心房600次/min快速起搏,诱发并维持房颤2 h,起搏前半小时静推L-CN(300 mg/kg),继以2.5mg/(kg.min)(液速50 ml/h)维持静脉点滴2 h。在不同观察时间点测定房颤前后电生理指标及静脉血氧化及抗氧化指标的变化。结果:①房颤后NS组心房有效不应期(AERP)显著缩短(P<0.01),AERP的频率适应性显著下降(P<0.01);L-CN组房颤前后AERP和频率适应性无显著缩短;L-CN组较NS组房颤诱发率明显降低(P<0.05)。②NS组房颤时静脉血氧化应激产物较NC组显著增多(P<0.05),抗氧化指标显著下降(P<0.01)。③L-CN组丙二醛(Malondialdehyd,MDA)生成显著减少(P<0.01),超氧化物歧化酶(superoxide dismutase,SOD)显著增加(P<0.05)。结论:L-CN对房颤时氧化应激及电重构有明显保护作用,这种保护机制可能通过清除自由基,抑制脂质过氧化而发挥作用。AIM： To evaluate the anti-oxidative stress effects of L-carnitine（L-CN） on tachycardia-induced acute atrial electrical remodeling in dogs.METHODS： Eighteen dogs were randomly divided into three groups： normal saline（NS） group,L-CN group and normal control（NC） group.In both NS and L-CN groups,right atrium was paced at 600 beats per minute（bpm） to induce atrial fibrillation（AF） and maintained for 2 h;0.9% normal saline（300 mg/kg,IV） or L-carnitine（300 mg/kg,IV） was given before the pace and 0.9% normal saline or L-carnitine [2.5 mg/（kg·min）,50 ml/h,ID] was administered for 2 h.The observed atrial electrophysiology indexes included atrial effective refractory period（AERP）,index of the AERP rate adaptation（AERP200/AERP150）/50 msec,conduction velocity（CV） and AF induced rate.Oxidation index of malondialdehyde（MDA） and antioxidation index of superoxide dismutase（SOD） of venous blood were measured before and 1 and 2 h after AF was measured.RESULTS： AERP shortened dramatically 2 h after AF（P〈0.01） in NS group but no remarkable change was found in L-CN group.AERP rate adaptation in the right atrium decreased significantly（P〈0.01） in NS group but did not change obviously in L-CN group.The AF-induced rate in L-CN group was significantly reduced（P〈0.01）.The oxidation index level（MDA） was increased and anti-oxidation index level（SOD） was decreased in both NS group and L-CN group（P〈0.05）.L-CN group had a lower MDA level and a higher SOD level compared with those in NS group（P〈0.01）.CONCLUSION： L-CN prevents tachycardia-induced oxidative stress and acute atrial electrical remodeling in dogs,possibly by cleaning the reactive oxygen species and inhibiting lipid peroxidation.

关 键 词：心房颤动 犬 氧化应激 电重构 左旋卡尼汀 

分 类 号：R541.7[医药卫生—心血管疾病]