Calcium modulation of exocytosis-linked plasma membrane potential oscillations in INS-1 832/13 cells

In the presence of high glucose or pyruvate, INS-1 832/13 insulinoma cells undergo stochastic oscillations in plasma membrane potential (Δψp) leading to associated fluctuations in cytosolic free Ca(2+) concentration ([Ca(2+)]c). Oscillations are not driven by upstream metabolic fluctuations, but rather by autonomous ionic mechanisms, the details of which are unclear. We have investigated the nature of the oscillator, with simultaneous...