Modelling calcium handling in cardiac cells

This review covers the key components of calcium handling in cardiac ventri cular myocytes. Specifically, L-type current, ryanodine receptors, the diad ic space, SERCA pump uptake into sarcoplasmic reticulum, sodium-calcium exc hangers, and calcium-binding proteins are reviewed with special focus on at tempts to mathematically model these entities. In addition to purely single entities, the review covers other models that have attempted to capture th e highly interactive and complex Ca sig nailing resulting from the interpla y of the key components above. These integrative models range in level from microscopic domains to whole cells including electrophysiological mechanis ms. In many cases, the differences in competing models reflect the controve rsies and uncertainties about the underlying biophysical mechanisms. Ultima tely, each level of modelling, along with experimental work, will be needed to help elucidate the cellular physiology of this fundamental cardiac sign alling system.