Hysteresis, Resonant Activation and Stochastic Resonance
in a Model Channel System with Time-Dependent Transition Rates

We study noise-induced resonant effects in a cyclically perturbed bistable system that models kinetics of a voltage-activated ion channel. Rates of transitions between open and closed states of the channel are modeled by introducing the real value ``reaction coordinate'' that parametrizes the protein's conformational change. In the high friction limit, variations of the control parameter (an activating voltage) lead to a time-delayed response of the system, i.e. to a dynamic hysteresis. Occurrence of the phenomenon is analyzed along with the conditions leading to the stochastic resonance (SR) and resonant activation (RA).