Figure 5. Analysis of the bidirectional Ca²⁺ flux between the cytosol and the mitochondria, J_x.

(A) Effect of altering J_x on the simulated Ca²⁺ oscillations. The black curve shows oscillations for the default value (k_x = 0.008 s⁻¹) given in Table 1, while the red curve shows oscillations obtained when k_x = 0. In the latter case, the period of oscillations is slightly increased. IP₃ = 1 μM. (B) Experimental investigation of the effect of inhibiting the mPTP with CSA (1 μM) on the period of Ca²⁺ oscillations in Hela cells. n = 64, 18, 16, 14 for control cells (0.3 and 10 μM histamine) and CSA-treated cells (0.3 and 10 μM histamine), respectively. Two groups were compared with an unpaired student’s t-test and two-tail p-value. Results were considered statistically significant when p < 0.05 (*p < 0.05 and **p < 0.01).