夹竹桃麻素对兔心房电重构的影响

目的探讨烟酰胺腺嘌呤二核苷酸磷酸氧化酶抑制剂夹竹桃麻素对兔心房急性电重构的预防作用。方法选择新西兰白兔18只,随机分为对照组、心房快速起搏组和夹竹桃麻素+心房快速起搏组(夹竹桃麻素组),每组6只。对照组和心房快速起搏组术前生理盐水3 ml/(kg·d)灌胃3 d,夹竹桃麻素组予30 mg/(kg·d)药物灌胃3d。对照组术中不行心房快速起搏,心房快速起搏组与夹竹桃麻素组术中以最快的能维持心房1:1起搏的频率(500～600/min)给予快速刺激。分别在0、0.5、1.0、1.5、2.0、2.5和3.0 h时,测量基础刺激周长分别为200 ms和1 50 ms的右心房有效不应期(atrial effective rcfractory period,AERP),分析AERP频率适应性的变化,并记录心房颤动(房颤)的诱发情况。结果对照组和夹竹桃麻素组AERP_(200)和AERP_(150)无明显变化,心房快速起搏组AERP_(200)和AERP_(150)与心房快速起搏时间呈负相关(r=—0.650,P<0.01;r=—0.498,P<0.01);对照组和夹竹桃麻素组AERP频率适应性指标无明显变化,心房快速起搏组AERP频率适应性与心房快速起搏时间呈负相关(r=一0.341,P<0.05);心房快速起搏组和夹竹桃麻素组的房颤诱发率分别为66.67%和16.67%,平均房颤持续时间分别为37.75 min和0.67 min,差异有统计学意义(P<0.05)。结论夹竹桃麻素能够减缓心房电重构的发生、发展,降低房颤的持续时间。

Effect of apocynin on atrial electrical remodeling in rabbits

Objective To investigate the effect of apocynin,a NADPH oxidase inhibitor,on atrial electrical remodeling in rabbits.Methods Eighteen rabbits were randomly assigned to three groups:control group,rapid atrial pacing(RAP) group and apocynin plus rapid atrial pacing (APO + RAP) group.Normal saline was given intragastricaly in control and RAP group for 3 days before electrophysiology study.Apocynin 30 mg/(kg ? d) was given in group APO + RAP instead.In both RAP and APO+RAP groups,right atrium was paced at 500 to 600 beats/min for 3 hours.Right atrial effective refractory period(AERP) was measured at the basic cycle length of 200 ms and 150 ms every 0.5 hour,the changes of rate adaptation of AERP and the inducibility of atrial fibrillation were analyzed.Results AERP_(200) and AERP_(150) did not change obviously in control and APO + RAP groups,they correlated negatively with the duration of RAP in RAP group(r =—0.650,P<0.01;r =- 0.498,P<0.01,respectively).Rate adaptation of AERP showed no significant change in control and APO + RAP groups,whereas there was a negative correlation between rate adaptation of AERP and duration of RAP in RAP group(r =- 0.341, P<0.05).In RAP group and APO + RAP group,the inducibility of AF was 66.67%and 16.67 %,respectively.The average duration of induced AF was 37.75 min and 0.67 min respectively (P<0.05).Conclusion Apocynin attenuates the development of atrial electrical remodeling and reduce the duration of atrial fibrillation in this model.