DUAL INNERVATION OF THE FOLIATE PAPILLAE OF THE RAT: AN ELECTROPHYSIOLOGICAL STUDY

The dual innervation of the foliate papillae of the rat by thechorda tympani and the glossopharyngeal nerves was determinedin this electrophysiological study. The magnitude of the chordatympani response to the chemical stimulation of the foliatepapillae was small and variable in different animals. Summatedresponses of both the chorda tympani and the glossopharyngealnerves to the stimulation of the foliate papillae showed similarpatterns such as long latencies, slowly rising responses afteronset of stimulation and slow declines by water ringing. Therelative responsiveness to 5 different chemicals applied tothe foliate papillae were almost the same for the chorda tympaniand the glossopharyngeal nerves. However, these 2 nerves produceddifferent patterns of response to various chemicals appliedto the fungiform, foliate and circumvallate papillae.