Electrical gap junction and second messenger coupling strengths. The inter-ICC coupling strengths impact GMN entrainment, gastric slow-wave velocity and pacemaker frequency.

(A, E)G_ICC−ICC and P_IP3 are altered for the simulations in Fig 5B–5D and Fig 5F–5H, respectively. (B) Spatiotemporal map of membrane potential (B1), Relative Lags (B2), and spatiotemporal map of SM Cell Periods (B3) for the network when G_ICC−ICC = 0.35 nS (left panels, partially entrained) and 1.4 nS (right panels, entrained). (C) The Total Lag for changes in G_ICC−ICC is shown for the last 7 cycles of 900-sec simulations for different conductance values (nS) indicated by the color legend. The two distinct classes of responses are enlarged in the right panels (lower ones entrained, upper ones partially entrained). An increase in Total Lag indicates decrease in slow-wave velocity. (F) Spatiotemporal maps of membrane potential (F1), Relative Lags (F2), and spatiotemporal maps of SM Cell Periods (F3) for the network when P_IP3 = 4.0 sec^-1 (left panels, partially entrained) and 16.0 sec^-1 (right panels, entrained). The spatiotemporal membrane potential diagrams are shown for the last 120 seconds of the respective simulation, whereas the Relative Lag and the SM Cell Period diagrams are shown for the last 20 cycles of the respective simulation. (G) The Total Lag for changes in P_IP3 is shown for the last 7 cycles of 900-sec simulations for different conductance values (nS) indicated by the color legend. (D, H) For several networks, the mean Total Lag (odd numbered panels) and the SM Cell Period (even numbered panels) of the last 7 cycles for each network with respect to its G_ICC−ICC and P_IP3 can be fit by individual exponential function, respectively. For increasing values of G_ICC−ICC, an exponential fit (, where a₁ = 8.65, β₁ = 0.75, a₂ = 18.23, β₂ = 17.87) has been drawn along the mean value of Total Lag and for increasing values of P_IP3, another exponential fit (, where a₁ = 7.44, β₁ = 1.70e5, a₂ = 32.07, β₂ = 9.37) has been drawn along the mean values of Total Lag. Partially entrained networks have not been considered for equation fitting. For SM Cell Period calculation, the last cell (42^nd cell) has been considered as the representative cell of the network. An increase in Total Lag indicates decrease in slow-wave velocity while a decrease in SM Cell Period indicates increase in pacemaking frequency.