素对狗上心膜,中心脏和内心脏的再极化的影响:I. 在体外试验研究研究
E A Sosunov1, E P Anyukhovsky, M R Rosen
1Department of Pharmacology and Pediatrics, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.
Circulation
|December 24, 1997
概括
素在心肌 (M) 细胞中与表心和内心细胞相比,对心细胞动作潜力持续时间 (APD) 的影响不同. 这些对APD的多样化影响可能解释素复杂的抗失常和前失常作用.
科学领域:
- 心血管生理学心血管生理学
- 电子生理学 电子生理学
- 药理学 药理学 是一个学科.
背景情况:
- 奎尼丁的抗失律作用包括减缓导电和再极化.
- 之前的研究表明,在孤立的组织中,素和作用潜能持续时间 (APD) 之间存在不一致的相关性.
研究的目的:
- 调查素对APD的作用机制.
- 为了比较素对犬类心脏上部,心脏中部 (M细胞) 和心脏内脏组织APD的影响.
主要方法:
- 使用标准的微电极技术来评估APD.
- 在各种周期长度 (300-4000毫秒) 中研究了素 (2.5-20微摩尔/升) 的作用.
- 采用E4031和四极毒素 (TTX) 来阐明离子通道参与.
主要成果:
- 观察到M细胞与其他区域的质量不同的时间过程和度/速率依赖的效应.
- 奎尼丁在内心和上心细胞中引起单调的APD延长.
- 在M细胞中,素的影响从APD延长到缩短,受超,度和周期长度的影响.
结论:
- 在实验室中,与心上/内心细胞相比,素对M细胞的影响存在显著的差异.
- 这些差异可能源于不同心脏部位对APD的离子通道贡献的变化.
- 显著的细胞反应可能会影响素的心脏再极化作用,影响其前节律和抗节律性质.
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