...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Basic Research in Cardiology >Endothelin-B receptors and ventricular arrhythmogenesis in the rat model of acute myocardial infarction
【24h】

Endothelin-B receptors and ventricular arrhythmogenesis in the rat model of acute myocardial infarction

机译：急性心肌梗死大鼠模型中内皮素B受体与室性心律失常的发生

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The arrhythmogenic effects of endothelin-1 (ET-1) are mediated via ETA-receptors, but the role of ETB-receptors is unclear. We examined the pathophysiologic role of ETB-receptors on ventricular tachyarrhythmias (VT/VF) during myocardial infarction (MI). MI was induced by coronary ligation in two animal groups, namely in wild-type (n = 63) and in ETB-receptor-deficient (n = 61) rats. Using a telemetry recorder, VT/VF episodes were evaluated during phase I (the 1st hour) and phase II (2–24 h) post-MI, with and without prior β-blockade. Action potential duration at 90% repolarization (APD90) was measured from monophasic epicardial recordings and indices of sympathetic activation were assessed using fast-Fourier analysis of heart rate variability. Serum epinephrine and norepinephrine were measured with radioimmunoassay. MI size was similar in the two groups. There was a marked temporal variation in VT/VF duration; during phase I, it was higher (p = 0.0087) in ETB-deficient (1,519 ± 421 s) than in wild-type (190 ± 34 s) rats, but tended (p = 0.086) to be lower in ETB-deficient (4.2 ± 2.0 s) than in wild-type (27.7 ± 8.0 s) rats during phase II. Overall, the severity of VT/VF was greater in ETB-deficient rats, evidenced by higher (p = 0.0058) mortality (72.0% vs. 32.1%). There was a temporal variation in heart rate and in the ratio of low- to high-frequency spectra, being higher (<0.001) during phase I, but lower (p < 0.05) during phase II in ETB-deficient rats. Likewise, 1 h post-MI, serum epinephrine (p = 0.025) and norepinephrine (p < 0.0001) were higher in ETB-deficient (4.20 ± 0.54, 14.24 ± 1.39 ng/ml) than in wild-type (2.30 ± 0.59, 5.26 ± 0.67 ng/ml) rats, respectively. After β-blockade, VT/VF episodes and mortality were similar in the two groups. The ETB-receptor decreases sympathetic activation and arrhythmogenesis during the early phase of MI, but these effects diminish during evolving MI. Keywords Endothelin - B-receptors - Myocardial infarction - Ventricular arrhythmias
机译：内皮素-1（ET-1）的心律失常作用是通过ETA受体介导的，但ETB受体的作用尚不清楚。我们检查了心肌梗死（MI）期间ETB受体对室性快速性心律失常（VT / VF）的病理生理作用。在两个动物组中，通过冠状动脉结扎诱导MI，即在野生型（n = 63）和ETB受体缺陷型（n = 61）大鼠中。使用遥测记录仪，在心梗后I期（第一小时）和II期（2-24小时）内评估VT / VF发作情况，有无β-受体阻滞。从单相心外膜记录中测量90％复极时的动作电位持续时间（APD90），并使用心律变异性的快速傅立叶分析评估交感神经激活指数。用放射免疫测定法测定血清肾上腺素和去甲肾上腺素。两组的心梗大小相似。室速/室颤持续时间有明显的时间变化；在第I阶段，ETB缺乏的大鼠（1,519±421 s）高于野生型（190±34 s）大鼠（p = 0.0087），但ETB缺乏的大鼠（p = 0.086）则较低（p = 0.086）。在第二阶段，比野生型（27.7±8.0 s）大鼠多出4.2±2.0 s）。总体而言，ETB缺陷型大鼠的VT / VF严重程度更高，其死亡率更高（p = 0.0058）（72.0％vs. 32.1％）。在ETB缺乏的大鼠中，心率和低频频谱比率与高频频谱比率存在时间变化，在I期较高（<0.001），而在II期较低（p <0.05）。同样，心梗后1小时，ETB缺乏（4.20±0.54，14.24±1.39 ng / ml）的血清肾上腺素（p = 0.025）和去甲肾上腺素（p <0.0001）高于野生型（2.30±0.59， 5.26±0.67 ng / ml）大鼠。 β-受体阻滞后，两组的VT / VF发作和死亡率相似。 ETB受体在MI的早期减少交感神经激活和心律失常，但是在MI发展的过程中这些作用减弱。内皮素-B受体-心肌梗塞-室性心律失常

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号