概括
加快室内逃逸 (AVE) 和重复室内反应 (RVR) 很难用大多数抗失常药物抑制. 只有阿普林丁在抑制狗的这些心律失常方面表现出100%的成功.
科学领域:
- 心脏病学 心脏病学
- 药理学 药理学是指药理学的学科.
- 兽医医学 兽医医学 兽医医学
背景情况:
- 在狗中,Ouabain的使用可以诱导心律失常,如加速腹腔逃逸 (AVE) 和重复腹腔响应 (RVR).
- 这些心律失常的特点是对照对象的稳定逃脱间隔.
- RVR和AVE的离子基础在很大程度上是未知的,尽管缓慢的电流可能参与其中.
研究的目的:
- 在狗模型中评估各种抗心律失常药物的有效性,以抑制ouabain诱导的AVE和RVR.
- 调查特定离子和药物类别在管理这些心室失常症中的作用.
主要方法:
- 给三组狗进行了ouabain的治疗,以诱导AVE和RVR.
- 测试了各种抗节律药物 (金尼丁,利多卡因,普罗卡因胺,普罗兰诺洛尔,维拉帕米尔,阿普林丁) 和干预措施 (KCl,化) 的抑制作用.
- 对照犬被监测到稳定的逃脱间隔.
主要成果:
- 大多数测试的抗失常药物在抑制AVE和RVR方面表现出有限的成功 (0-33%) .
- 甲是无效的;玻尿酸维拉帕米尔显示部分抑制 (21-41%).
- 连续输注维拉帕米尔和KCl输注 (将血清升至7.2mEq/L) 是有效的.
- 阿普林丁 (2.86 mg/kg) 在所有狗中实现了100%的AVE和RVR抑制.
- 化逆转了阿普林丁和维拉帕米尔诱导的抑制作用.
结论:
- 乌阿巴因诱导的AVE和RVR通常在临床剂量下耐受于常用的抗心律失常药物的抑制.
- 阿普林丁是唯一一种在这种狗模型中显示出完全有效的药物.
- 这些发现表明慢电流在这些心律失常的发病过程中可能发挥作用,并强调阿普林丁作为一个有前途的治疗选择.
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