Used primarily in scientific research to study calcium signaling in cells, especially in muscle and nerve tissues. It binds to ryanodine receptors on the sarcoplasmic reticulum, which are responsible for releasing calcium ions during muscle contraction. By modulating these receptors, it helps researchers investigate the mechanisms of excitation-contraction coupling, arrhythmias, and diseases like malignant hyperthermia and heart failure. At low concentrations, it locks the receptor in a partially open state, while at high concentrations, it blocks the channel completely. This dual action makes it a valuable tool in pharmacology and physiology for probing intracellular calcium dynamics.