Colored noises and time delay induced periodic square calcium wave

Intracellular calciumoscillation with colored noises and same time delay tau in active and passive transport processes of intracellular Ca2+ is investigated by the means of second-order algorithm for stochastic simulation colored noises. By simulating time series, stationary probability distribution and average of intracellular Ca2+ concentrations, we obtain the results which indicate that is anti-synchronous between calcium store and cytosol and the critical phenomenon of time delay with critical value tau(c) similar or equal to 0: 1 s, appears. As tau -> 0.1 s or as correlation time tau(1) of colored noises increases, the stability of system is strengthened. Especially, the long tau and tau(1) induce periodically square calcium wave. Additionally, as tau(1) prolongs, the average of Ca2+ concentrations of cytosol and calcium store respectively always increases and maintains a constant value.