Fig. S1.

Damage-induced responses of type II afferents were insensitive to block of glutamate receptors. (A) Loose-patch extracellular recording of action potentials from a type II afferent following OHC ablation (at arrow). (B) A mixture of glutamate receptor blockers, including 50 µM APV, 50 µM CNQX, and 1 mM MCPG to block NMDA, AMPA/kainate, and metabotropic glutamate receptors had no effect (n = 4 afferents). (C) Type II response to OHC ablation after removal of glutamate receptor blockers. This burst of action potentials occurred <1 s after OHC ablation, during the peak depolarization of the type II fiber (Fig. 2A). Similar to the early inward current seen in voltage-clamp recording, this damaged-induced burst of action potentials also was unaffected by the purinergic antagonist PPADS (n = 2 afferents).