Zinc controls RyR2 activity during excitation-contraction coupling

Figures & data

Figure 1. A model to show how zinc may regulate RyR2-mediated sarcoplasmic reticulum calcium release. Physiological conditions: During the resting phase of the cardiac cycle RyR2 is closed as the cytosolic [Ca²⁺] is sub-activating (100 nM). The normal trigger for RyR2 activation during systole is a transient rise in [Ca²⁺] (≥ 1 µM). Zn²⁺-dyshomeostasis: If the intracellular [Zn²⁺] rises >1 nM, the dependency on Ca²⁺ for RyR2 openings is removed and Zn²⁺ becomes the activating ligand. This leads to abnormally active channels.