Fig. 4.

KCNQ channels regulate type II afferent excitability. (A) XE-991 (KCNQ blocker) reversibly eliminated the UTP-evoked ramp current. I–V relation of UTP before (black), during (red), and after (gray) XE-991 application. (B) Retigabine (KCNQ opener) induced outward current at −60 mV in type II cochlear afferents. (C) Current step protocol (1pA steps) to evoke action potentials (Ci). In UTP, from the same resting membrane potential, action potentials were evoked by smaller current steps (Cii). (D) The KCNQ channel activator retigabine reversibly prevented the response of type II afferents to OHC ablation (n = 5 afferents).