长期高血浆去甲肾上腺素对兔心室肌电生理的影响  

The Effect of Chronic High Plasma Norepinephrine Level on Electrophysiology of Ventricular Myocardium in Rabbit.

作　　者：刘文举[1] 黄从新[1] 赵庆彦[1] 王腾[1] 白玉鹏[1] 

机构地区：[1]武汉大学人民医院心内科,湖北武汉430060

出　　处：《中国心脏起搏与心电生理杂志》2005年第5期379-381,共3页Chinese Journal of Cardiac Pacing and Electrophysiology

摘　　要：探讨长期高血浆去甲肾上腺素(NE)对兔心室肌电生理的影响。取成年新西兰大耳白兔30只,雌雄不拘,随机等分为3组,分别给予腹腔注射NE1.0mg/kg、0.5mg/kg和生理盐水1ml,一日两次,连续15天,分别作为NE高、低剂量组和对照组。利用自制复合电极同步记录电刺激前后左室内、中、外3层心肌单向动作电位(MAP)及心电图,观察比较3组MAP复极90%的时程(MAPD90)、跨壁复极离散度(TDR)、后除极及室性心律失常的诱发情况。结果:TDR及3层心肌的MAPD903组之间无差异。NE高、低剂量组中层心肌的MAP图形2期拱顶呈消失趋势;程序刺激下NE高剂量组早期或延迟后除极及室性心律失常发生率较对照组均明显增加(P<0.05),但无持续性室性心动过速、心室扑动、心室颤动发生;NE低剂量组仅频发或成对室性早搏发生率与对照组差异具有显著性,后除极和非持续性室性心动过速发生增加,但无显著性差异。结论:长期高血浆NE易诱发室性心律失常的原因可能与心室肌后除极的发生率升高及2相折返的形成有关。To investigate the chronic effect of the norepinephrine （NE） on the transmural dispersion of left ventricular repolarization in intact rabbits ,30 rabbits were randomly divided into three groups, giving separately NE1.0 mg/kg , 0.5 mg/kg, and sodium chloride 1 ml,twice one day for 15 days,as high NE dose group,low NE dose group and control group. With the monophasic action potential （MAP） recording technique, MAP of the epicardium （Epi）,endocardium （Endo）, and midmyocardium（Mid） were recorded simultaneously by specially designed plunge-needle electrodes at the left ventricular free walls. 90% repolarization（ MAPDg0 ）and transmural dispersion of repolarization （TDR） among three myocardial layers as well as the incidence of the early afterdepolarization（ EAD）, delay afterdepolarization （DAD） and ventricular arrhythmia were compared among three groups. Results： The TDR and MAPDg0 of Endo, Mid and Epi in high NE dose group, low NE dose group and control group have no significant change. Compared with control group ,the graphics of MAP in high and low NE dose group changed ,and the dome of phase 2 became steep and EAD was elicited significantly high in 7 rabbits（70 % ） in high NE dose group and 6 in low NE dose group（60% ）, compared with the control group（ 10% ） （P 〈 0.05 ）. Conclsions ： Chronic high plasma NE level probably induces ventricular arrhythmia via promoting EAD/DAD and phase 2 reentry. [ Chinese Journal of Cardiac Pacing and Electrophysiology,2005,19（5） ：379 -381 ]

关 键 词：电生理学 去甲肾上腺素 心室肌 单向动作电位 兔 

分 类 号：R971.93[医药卫生—药品] R331.38[医药卫生—药学]