Size Matters: Ryanodine Receptor Cluster Size Affects Arrhythmogenic Sarcoplasmic Reticulum Calcium Release.

ABSTRACT:

Background

Ryanodine receptors (RyR) mediate sarcoplasmic reticulum calcium (Ca²⁺) release and influence myocyte Ca²⁺ homeostasis and arrhythmias. In cardiac myocytes, RyRs are found in clusters of various sizes and shapes, and RyR cluster size may critically influence normal and arrhythmogenic Ca²⁺ spark and wave formation. However, the actual RyR cluster sizes at specific Ca²⁺ spark sites have never been measured in the physiological setting.

Methods and results

Here we measured RyR cluster size and Ca²⁺ sparks simultaneously to assess how RyR cluster size influences Ca²⁺ sparks and sarcoplasmic reticulum Ca²⁺ leak. For small RyR cluster sizes (<50), Ca²⁺ spark frequency is very low but

SUBMITTER: Galice S 

PROVIDER: S-EPMC6064922 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature