Problems and paradigms: Oscillations and waves of cytosolic calcium: Insights from theoretical models

Oscillations in cytosolic Ca 2+ occur in a wide variety of cells, either spontaneously or as a result of external stimulation. This process is often accompanied by intracellular Ca 2+ waves. A number of theoretical models have been proposed to account for the periodic generation and spatial propagation of Ca 2+ signals. These models are reviewed and their predictions compared with experimental observations. Models for Ca 2+ oscillations can be distinguished according to whether or not they rely on the concomitant, periodic variation in inositol 1,4,5‐trisphosphate. Such a variation, however, is not required in models based on Ca 2+ ‐induced Ca 2+ release. When Ca 2+ diffusion is incorporated into these models, propagating waves of cytosolic Ca 2+ arise, with profiles and rates comparable to those seen in the experiments.