Sodium/bicarbonate cotransporter which plays an important role in regulating intracellular pH (PubMed:18319254). Has been shown to act as a sodium/bicarbonate cotransporter in exchange for intracellular chloride (By similarity). Has also been shown to act as a sodium/biocarbonate cotransporter which does not couple net influx of bicarbonate to net efflux of chloride, with the observed chloride efflux being due to chloride self-exchange (PubMed:18319254). Controls neuronal pH and may contribute to the secretion of cerebrospinal fluid (By similarity). Acting on presynaptic intracellular pH, it promotes GABA release, reduces the excitability of CA1 pyramidal neurons, and modulates short-term synaptic plasticity (By similarity). Required in retinal cells to maintain normal pH which is necessary for normal vision (By similarity). In the kidney, likely to mediate bicarbonate reclamation in the apical membrane of the proximal tubules (By similarity). {ECO:0000250|UniProtKB:Q5DTL9, ECO:0000250|UniProtKB:Q80ZA5, ECO:0000269|PubMed:18319254}. This is the function of SLC4A10 (solute carrier family 4 member 10, Ensembl gene identifier ENSG00000144290).