VOLTAGE FLUCTUATIONS AND COLLECTIVE EFFECTS IN ION-CHANNEL PROTEIN ENSEMBLES

We study experimentally the noise in ensembles of voltage-gated ion ch annels. The coupling between the microscopic state of the channels and the macroscopic voltage fluctuations leads to collective effects whic h (i) induce damped oscillations in the voltage noise and (ii) reduce the voltage noise in absolute terms, with a stronger reduction for lar ger numbers of participating channels. These results are confirmed by numerical simulations and explained in the context of a simple model t hat presents the ensemble of channels as a damped harmonic oscillator.