Initial segment Kv2.2 channels mediate a slow delayed rectifier and maintain high frequency action potential firing in medial nucleus of the trapezoid body neurons.

The medial nucleus of the trapezoid body (MNTB) is specialized for high frequency firing by expression of Kv3 channels, which minimize action potential (AP) duration, and Kv1 channels, which suppress multiple AP firing, during each calyceal giant EPSC. However, the outward K(+) current in MNTB neurons is dominated by another unidentified delayed rectifier. It has slow kinetics and a peak conductance of approximately 37 nS; it is half-activated at -9.