Human Potassium, Sodium Hyperpolarization-activated Cyclic Nucleotide-gated Chan

Hyperpolarization-activated ion channel exhibiting weak selectivity for potassium over sodium ions.

Contributes to the native pacemaker currents in heart (If) and in neurons (Ih).

Can also transport ammonium in the distal nephron.

Produces a large instantaneous current.

Modulated by intracellular chloride ions and pH; acidic pH shifts the activation to more negative voltages (By similarity).