Voltage gated potassium (Kv) channels represent the most complex class of voltage gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. KCNH3 is a pore forming (alpha) subunit of voltage-gated potassium channel. It elicits an outward current with fast inactivation.