Changes of the biophysical properties of voltage-gated Na+ currents during maturation of the sodium-taste cells in rat fungiform papillae

Taste cells are sensory receptors that undergo continuous turnover while they detect food chemicals and communicate with afferent nerve fibers. The voltage-gated sodium current (INa ) is a key ion current for generating action potentials in fully differentiated and chemo-sensitive taste cells, which use electrical signaling to release neurotransmitters. Here we show that, during the maturation of rat taste cells involved in salt detection (sodium cells), the biophysical properties of INa , such as voltage dependence of activation and inactivation, change significantly. Our results help understand how taste cells gain electrical excitability during turnover, a property critical to operate as chemical detectors that relay sensory information to nerve fibers.