科研之友
微信
新浪微博
Facebook
分享链接
摘要
Calcium sparks are local regenerative releases of Ca2+ from a cluster of ryanodine receptors on the sarcoplasmic reticulum. During excitation-contraction coupling in cardiac cells, Ca2+ sparks are triggered by Ca2+ entering the cell via the T-tubules (Ca2+-induced Ca2+ release). However under conditions of calcium overload, Ca2+ sparks can be triggered spontaneously. The exact process by which Ca2+ sparks terminate is still an open question, although both deterministic and stochastic processes are likely to be important. In this article, asymptotic methods are used to analyze a single Ca2+ spark model, which includes both deterministic and stochastic biophysical mechanisms. The analysis calculates both spark frequencies and spark duration distributions, and shows under what circumstances stochastic transitions are important. Additionally, a model of the coupling of the release channels via the FK-binding protein is analyzed.
- 出版日期2004-3
