Probable cation channel with high affinity for sodium. Homotrimer or heterotrimer with other ASIC proteins. Expressed in brain, spinal cord and dorsal root ganglion (DRG). Expressed by a subset of sensory neurons in the DRG. Expressed by granule cells in the cerebellar cortex. In hippocampus, expression is detected in dentate gyrus granule cells, in pyramidal cells of CA1-CA3 subfields and in interneurons of the striatum oriens and radiatum of all subfields. In cerebral cortex expressed in small, medium and large pyramidal cells in layers 2, 3 and 5 respectively. Also expressed in striatum, globus pallidus, inferior and superior calliculi, amygdala, magnocellular preoptic nucleus, islands of Calleja and large neurons of olfactory tubercules. Highly expressed in newborn spinal cord but hardly detected in the cerebellum compared to adult. Expressed at postnatal day 1 in ependymal cells lining the central canal of spinal cord and in motor neurons. In adult, expression decreases in ependymal cells and increases in motor neurons. The number of positive interneurons decreases but the individual interneuron expression increases in adult spinal cord compared to newborn. In vitro, has no proton-gated channel activity. Belongs to the amiloride-sensitive sodium channel (TC 1.A.6) family. ASIC4 subfamily.