How Noise and Coupling Induce Bursting Action Potentials in Pancreatic β-Cells

Unlike isolated β-cells, which usually produce continuous spikes or fast and irregular bursts, electrically coupled β-cells are apt to exhibit robust bursting action potentials. We consider the noise induced by thermal fluctuations as well as that by channel-gating stochasticity and examine its effects on the action potential behavior of the β-cell model. It is observed numerically that such noise in general helps single cells to produce a variety of electrical activities. In addition, we also probe coupling via gap junctions between neighboring cells, with heterogeneity induced by noise, to find that it enhances regular bursts.