The phenomena of an intracellular calcium oscillation system with non-Gaussian noises

Role of time delay on intracellular calcium dynamics driven by non-Gaussian noises

“…In this paper, x and y denote the concentration of free Ca 2+ of cytosol and calcium store in a cell, respectively. Based on calcium-induced calcium release, the Langevin equations of ICO system can be read as follows according to our previous result 7 :…”

“…By means of second-order stochastic Runge-Kutta type algorithm 43 , for the specific simulation algorithm of ICO system, see ref. 7 , discretize time in steps of size Δ = 0.001s, one can stochastically simulate the time evolution of intracellular Ca 2+ concentration in the cytosol x ( t ) and calcium store y ( t ). Experimentally, x is in the order of 100~200 nM in basal state 44 and y = 5 μ M 45 , so that the initial values x (0) and y (0) independently take uniformly random from 0.1~0.2 μ M and 4~5 μ M. In the condition of time delay, it is rational to let x ( t − τ ) = x (0) and y ( t − τ ) = y (0) as t < τ .…”

“…In many studies on intracellular calcium oscillation(ICO) system, there have been a variety of channels showing calcium-induced calcium release and a variety of models 1 2 3 4 , and some phenomena have been found. Such as stochastic resonance in mesoscopic stochastic model 5 and in ICO with Gaussian white noises and time delay 6 , reverse resonance in ICO with Gaussian colored noises and time delay 6 and in ICO with non-Gaussian noises 7 , coherence resonance in ICO with non-Gaussian noises 7 and in ICO with internal and external noises 8 , oscillatory coherence 9 and resonant activation 10 in ICO with Gaussian colored noises and time delay. Besides, calcium puffs has been found in neuronal cells 11 and in a model with clustered Ca 2+ release channels 12 , where, local waves, abortive waves, global oscillation and tide waves also have been exhibited.…”

“…In our research on ICO 6 7 9 10 36 37 38 39 40 41 , taking into account time delay in processes of active and passive transport of intracellular Ca 2+ , the roles of time delay and Gaussian colored noises on ICO system have been studied. In view of non-Gaussian noise in ICO with time delay, we have only studied the role of non-Gaussian noises on ICO, but the effect of time delay on ICO system has not been studied.…”

“…First, according to ref. 7 , the ICO model with non-Gaussian noises and time delay is presented. Then, the time delay, normalized autocorrelation function(NAF), and characteristic correlation time(CCT) of cytosolic and calcium store’s Ca 2+ concentration are respectively simulated.…”