Simulation of Store-Operated Calcium Entry in Neurons

Store-operated calcium entry (SOCE) is a unique Ca2+ entry pathway that is specifically activated by the depletion of Ca2+ from the endoplasmic reticulum (ER). This process is ubiquitous in non-excitable cells; in contrast, the role of SOCE in neurons is still poorly understood because of the complexity of Ca2+ influx mechanisms existing in these cells. However, growing evidence indicates that SOCE plays an important role in the maintenance of intracellular Ca2+ homeostasis, neuronal signaling, and plasticity, and this emphasizes the necessity to include SOCE in mathematical models of the calcium dynamics. Here we extend our previously published models of the calcium dynamics by incorporating the data on Ca2+-induced calcium release and SOCE based on the experimental results obtained mostly on cerebellar slices. Our simulations have shown that SOCE in neurons is probably necessary to maintain the calcium levels in the cytosol and ER and may influence repetitive Ca2+ signals in the case of significant store depletion. Modeling of SOCE, however, remains problematic because of the difficulty of experimental isolation of this process.