文化大學機構典藏 CCUR:Item 987654321/32089
English  |  正體中文  |  简体中文  |  全文笔数/总笔数 : 46867/50733 (92%)
造访人次 : 11887604      在线人数 : 805
RC Version 6.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
搜寻范围 查询小技巧：
  • 您可在西文检索词汇前后加上"双引号"，以获取较精准的检索结果
  • 若欲以作者姓名搜寻，建议至进阶搜寻限定作者字段，可获得较完整数据
    •  进阶搜寻
    主页 ‧ 登入 ‧ 上传 ‧ 说明 ‧ 关于CCUR ‧ 管理 到手机版


    jsp.display-item.identifier=請使用永久網址來引用或連結此文件: https://irlib.pccu.edu.tw/handle/987654321/32089


    题名: Leptin decreases heart rate associated with increased ventricular repolarization via its receptor
    作者: Lin, Yen-Chang
    Huang, Jianying
    Hileman, Stan
    Martin, Karen H.
    Hull, Robert
    Davis, Mary
    Yu, Han-Gang
    贡献者: 生科所
    关键词: leptin
    leptin receptor
    resting heart rate
    QT interval
    日期: 2015-12
    上传时间: 2016-02-26 11:09:32 (UTC+8)
    摘要: Leptin has been proposed to modulate cardiac electrical properties via beta-adrenergic receptor activation. The presence of leptin receptors and adipocytes in myocardium raised a question as to whether leptin can directly modulate cardiac electrical properties such as heart rate and QT interval via its receptor. In this work, the role of local direct actions of leptin on heart rate and ventricular repolarization was investigated. We identified the protein expression of leptin receptors at cell surface of sinus node, atrial, and ventricular myocytes isolated from rat heart. Leptin at low doses (0.1-30 mu g/kg) decreased resting heart rate; at high doses (150-300 mu g/kg), leptin induced a biphasic effect (decrease and then increase) on heart rate. In the presence of high-dose propranolol (30 mg/kg), high-dose leptin only reduced heart rate and sometimes caused sinus pauses and ventricular tachycardia. The leptin-induced inhibition of resting heart rate was fully reversed by leptin antagonist. Leptin also increased heart rate-corrected QT interval (QTc), and leptin antagonist did not. In isolated ventricular myocytes, leptin (0.03-0.3 mu g/ml) reversibly increased the action potential duration. These results supported our hypothesis that in addition to indirect pathway via sympathetic tone, leptin can directly decrease heart rate and increase QT interval via its receptor independent of beta-adrenergic receptor stimulation. During inhibition of beta-adrenergic receptor activity, high concentration of leptin in myocardium can cause deep bradycardia, prolonged QT interval, and ventricular arrhythmias.
    關聯: AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY 卷: 309 期: 10 頁碼: H1731-H1739
    显示于类别:[生物科技研究所 ] 期刊論文

    文件中的档案:

    档案 描述 大小格式浏览次数
    index.html0KbHTML287检视/开启


    检视Licence

    在CCUR中所有的数据项都受到原著作权保护.

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - 回馈