Effects of an electromagnetic field on intracellular calcium oscillations in a cell with external noise

Intracellular calcium ion concentration oscillation in a cell subjected to external noise and irradiated by an electromagnetic field is considered. The effects of the intensity E_0, the polar angle \theta and the frequency \omega of the external electric field on steady-state probability distribution and the mean Ca^2 + concentration, respectively, are investigated by a numerical calculation method. The results indicate that (i) variation of \omega cannot affect the intracellular calcium oscillation; (ii) the steady-state probability distribution presents a meaningful modification due to the variations of E_0 and \theta , while variation of \theta does not affect the steady-state probability distribution under the condition of a small E_0 , and E_0 cannot affect the steady-state probability distribution either when \theta = \pi/2; (iii) the mean Ca^2 + concentration increases as E_0 increases when \theta < \pi / 2 and, as \theta increases, it first increases and then decreases. However, it does not vary with E_0 increasing when \theta = \pi/2, but it increases with \theta increasing when E_0 is small.