The sodium pump controls the frequency of action-potential-induced calcium oscillations

Abstract

Calcium plays a significant role in a number of cellular processes, like muscle contraction, gene expression, synaptic plasticity, signal transduction, but the significance of calcium oscillations (CaOs) is not yet completely understood in most of the cell types. It is a widely accepted fact that CaOs are a frequency encoded signal that allows a cell to use calcium as a second messenger while avoiding its toxic effects. These intracellular CaOs are primarily driven by some agonist-dependent pathways or fluctuations in membrane potential. The present mathematical model is of the latter type. The model incorporates expression for all major intracellular ionic species and membrane proteins. Especially, it integrates the coupling effect of sodium pump and Na+ / Ca2+ exchanger over CaOs. By varying sodium pump current, it is found that, sodium pump is a key player in modulating intracellular CaOs. The model predicts that the sodium pump can play a decisive role in regulating intercellular cell signaling process. The present study forms the basis for sodium pump controlled intercellular signaling process and requires further experimental verification. Mathematical subject classification: 34M10, 92C20.