Currents from a simple three-state ion channel model. (A) Simulated currents from a model where the channels transit from a closed state C to an open state O (by the rate α) and then to the inactivated state I (by the rate γ). Both sets of parameters (α = 3 ms⁻¹ and γ = 1 ms⁻¹ or α = 1 ms⁻¹ and γ = 3 ms⁻¹) generated the same normalized current time course. (B) Slowing only the inactivation rate γ (from 1 ms⁻¹ to 0.5 ms⁻¹) changes both the activation time course and the inactivation time course.