期刊
CIRCULATION RESEARCH
卷 93, 期 1, 页码 40-45出版社
LIPPINCOTT WILLIAMS & WILKINS
DOI: 10.1161/01.RES.0000079967.11815.19
关键词
calcium homeostasis; sarcoplasmic reticulum; ryanodine receptors; confocal imaging; membrane transport
资金
- NHLBI NIH HHS [HL64098, HL30077] Funding Source: Medline
Free [Ca2+] inside the sarcoplasmic reticulum ([Ca2+](SR)) is difficult to measure yet critically important in controlling many cellular systems. In cardiac myocytes, [Ca2+](SR) regulates cardiac contractility. We directly measure [Ca2+](SR) in intact cardiac myocytes dynamically and quantitatively during beats, with high spatial resolution. Diastolic [Ca2+](SR) (1 to 1.5 mmol/L) is only partially depleted (24% to 63%) during contraction. There is little temporal delay in the decline in [Ca2+](SR) at release junctions and between junctions, indicating rapid internal diffusion. The incomplete local Ca2+ release shows that the inherently positive feedback of Ca2+-induced Ca2+ release terminates, despite a large residual driving force. These findings place stringent novel constraints on how excitation-contraction coupling works in heart and also reveal a Ca2+ store reserve that could in principle be a therapeutic target to enhance cardiac function in heart failure.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据