硝苯地平与间硝苯地平对美托洛尔撤药后大鼠缺血再灌心肌功能和β受体密度的影响  

Effects of nifedipine and menidipine on cardiac function and βadrenoceptor density in ischemicreperfused rat hearts after metoprolol withdrawal

作　　者：李庆平[1] 饶曼人[1] 

机构地区：[1]南京医科大学心血管药理学研究室

出　　处：《中国药理学与毒理学杂志》1998年第2期113-116,共4页Chinese Journal of Pharmacology and Toxicology

摘　　要：用离体大鼠心脏灌流模型，观察硝苯地平（Ｎｉｆ），间硝苯地平（Ｍｅｎ）对美托洛尔（Ｍｅｔ）连续用药撤药后缺血再灌心功能及心肌β受体密度变化的影响．缺血再灌使心脏收缩功能降低，心功能曲线压低；左室舒张末压（ＬＶＥＤＰ）和心脏压力－容积曲线上抬．Ｍｅｔ５０ｍｇ·ｋｇ－１·ｄ－１ｉｇ，２周，撤药１ｄ可使缺血再灌心功能略有改善．按上述Ｍｅｔ给药方案，最后３ｄ加Ｎｉｆ或Ｍｅｎ５ｍｇ·ｋｇ－１·ｄ－１，ｉｇ，并在缺血过程中加入Ｎｉｆ或Ｍｅｎ０．５μｍｏｌ·Ｌ－１可防止缺血再灌后左室收缩压，左室压最大变化速率及心率的降低，增加冠脉流量，减轻ＬＶＥＤＰ的上抬，使心功能曲线和压力－容积曲线接近正常．缺血再灌和Ｍｅｔ撤药后缺血再灌使心肌β受体密度增加，Ｎｉｆ或Ｍｅｎ可使之维持正常．本研究提示。The effects of nifedipine (Nif) and menidipine (Men) on cardiac function and myocardium βadrenoceptor density in isolated ischemicreperfused rat hearts after metoprolol (Met) withdrawal were investigated. Ischemia (60 min) and reperfusion (20 min) reduced left ventricular systolic function, held down the starling curve; lifted left ventricular end diastolic pressure (LVEDP) and the pressurevolume (PV) relationship curve. Met (50 mg·kg1·d1, ig, 2 weeks, withdrawal 1 d) slightly improved cardiac function. Met (administrated as above) plus Nif or Men (5 mg·kg1·d1, ig, from 3 d before experiment, 0.5 μmol·L1 for ischemia perfusion) significantly improved left ventricular systolic pressure, ±dp/dtmax, heart rate and coronary flow, decreased the abnormal rise of LVEDP, made both the starling and PV curves closing to the control. Myocardium βadrenoceptor density was increased after either Met withdrawal or/and ischemiareperfusion, Nif or Men kept the number of βadrenoceptor being normal. These results suggest that the protective effects of Nif and Men on ischemia reperfusion myocardium after Met withdrawal be related to their effects on the βadrenoceptor number stabilizing.

关 键 词：心肌缺血 再灌注损伤 硝苯地平 间硝苯地平 MET 

分 类 号：R542.1[医药卫生—心血管疾病] R972[医药卫生—内科学]