Neural responses of the glossopharyngeal nerve to several bitter stimuli in mice.

The neural reaction to bitter stimuli was tested in the glossopharyngeal (GL) and chorda tympani (CT) nerves of mice. Relative responses to several bitter stimuli (quinine, iso-alpha-acids, L-tryptophan and L-phenylalanine) were greater in the GL nerve than in the CT nerve. Strain variability for taste sensitivity to bitter stimuli existed between two strains (C57BL and BALB/C). The GL nerve response to caffeine, iso-alpha-acids and L-phenylalanine in the BALB/C strain was greater than the response in the C57BL strain.