Hyperpolarization Activated Cyclic Nucleotide Gated Potassium Channel 3 (HCN3)

HCN3 conducted both potassium and sodium ions with a 3:1 preference for potassium ions. HCN3 bound cAMP, but unlike other HCNs, its activity was not modulated by intracellular cAMP.The cDNA contains a repetitive element in its 3-prime proximal region, and the deduced protein contains 703 amino acids. RT-PCR ELISA detected high HCN3 expression in adult liver and kidney and fetal liver and brain, intermediate expression in adult whole brain, lung, pancreas, spleen, testis, ovary, and all specific brain regions examined, and little to no expression in heart and skeletal muscle.Expression was high in fetal brain and adult cerebellum and intermediate in nucleus accumbens, thalamus, and pituitary gland, with little to no expression in other brain regions examined.