Simulation of the fibroblast effect on electrical activity of sinoatrial node cells

Effects of fibroblast‐myocyte coupling on the sinoatrial node activity: A computational study

“…In comparison, SAN cells are larger, with 20‐pF capacitance of central and 60 pF of peripheral cells . In the simulations, we observed that 2 fibroblasts are enough to suppress spontaneous activity of a central SAN cell and to establish the potential of V rs = −44 mV in the system of these coupled cells. This value, V rs , is an analogue of a “resting potential” for this system of coupled cells.…”

“…This value, V rs , is an analogue of a “resting potential” for this system of coupled cells. On the other hand, 4 fibroblasts attached to a peripheral SAN cell resulted in just a 3% change of its CL . This unequal effect of fibroblasts on SAN cells actually stands behind the effects described above.…”

“…Surprisingly, fibroblasts hardly affected the CL, unlike in the case of pairs of coupled cells: It was 0.26 second without ACh and 0.49 second after ACh superfusion (Figure ), except for a short period of transients after t = 60 seconds.…”

“…The established CL in the system is close but not equal to the faster‐oscillating cell (peripheral SAN) CL, and the faster‐oscillating cell is first to depolarize. The distribution of the SAN cells was the same in the simulations presented above, while fibroblasts' effect on peripheral SAN cell action potential is minimal . As a consequence, we did not observe any significant effect of fibroblasts on the frequency of the SAN.…”

“…The role and the effect of fibroblast‐myocyte coupling on electrical activity of the SAN open novel fields to study. Computer simulations of isolated SAN cells coupled to fibroblasts show pronounced reduction of central SAN cell cycle length (CL) and action potential amplitude, while peripheral cells' action potential changes were relatively weak . Here, we present results of detailed computer simulations of SAN electrical activity affected by fibroblasts.…”