Sample recordings of Glc-, Suc SC best (PI)- and Mix-type single fibres from the chorda tympani nerves of WT mice. Stimuli were 0.5 mol/L Suc, 0.5 mol/L Glc, 0.5 mol/L Glc + 10 mmol/L NaCl, 1 mmol/L SC, 0.01 mol/L HCl, 0.1 mol/L NaCl, 0.1 mol/L MPG and 20 mmol/L QHCl. Lines indicate application of stimuli to the tongue. QHCl, quinine HCl; WT, wild-type