Fig. 4.

HCN currents of mouse cones, measured with voltage-clamp. Leak-subtracted currents from cone held at − 50 mV and stepped for 400 ms to potentials of − 25 to − 135 mV in increments of 10 mV. Gray lines are fits to single exponential functions to give activation time constants, which varied from 25 ms near rest to less than 10 ms for strong hyperpolarizing steps. We observed no significant inactivation. From [53]