在短期心房电生理学改造中Na(+) /H(+) 交换器的作用
J V Jayachandran1, D P Zipes, J Weksler
1Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
Circulation
|April 19, 2000
概括
Na+/H+交换器 (NHE) 的激活有助于从快速心房率开始的电生理学重塑 (ER). 抑制NHE可以防止ER,在快速节奏和缺血期间保持心房功能.
科学领域:
- 心脏病学 心脏病学
- 电子生理学 电子生理学
- 细胞生理学 细胞生理学
背景情况:
- 由于心房速率快,电生理学重塑 (ER) 的机制仍然不清楚.
- 本研究研究了ER中Na+/H+交换器 (NHE) 的作用,假设其通过缺血的激活有助于这一过程.
研究的目的:
- 确定因缺血导致的NHE激活是否有助于ER.
- 为了评估NHE抑制在模拟快速心房率和实际缺血期间对ER的影响.
主要方法:
- 在自主封锁下研究了28只狗.
- 在闭胸犬中,通过快速心房节奏 (5小时每分钟600次) 模拟心房动,其中一些接受了选择性NHE抑制剂 (HOE642).
- 在开放胸部的狗中引发了右心房缺血症,其中一些接受了HOE642或glibenclamide.
主要成果:
- 在节奏狗中,NHE抑制阻止了心房有效耐火期 (AERP) 的缩短,并保持了速度适应.
- 在患有诱导性缺血症的狗中,NHE抑制阻止了AERP缩短并维持了速率适应,与glibenclamide治疗不同.
- 在模拟的快速速度和缺血条件下,NHE抑制成功地保持了心房电生理学特性.
结论:
- 激活NHE是推动短期电生理学改造的关键机制.
- 抑制NHE可以防止心房电生理学的有害变化,这是由快速节奏和缺血引起的.
- 准NHE可能提供一种治疗策略,以管理心房律乱和相关的重塑.
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