TASTE RESPONSES TO BINARY-MIXTURES OF AMINO-ACIDS IN THE SEA CATFISH,ARIUS-FELIS

In vivo electrophysiological recordings in the sea catfish, Arius feli s, showed that the magnitude of the integrated facial taste responses to binary mixtures of amino acids was predictable with knowledge obtai ned from previous cross-adaptation studies of the relative independenc e of the respective binding sites of the component stimuli. Each compo nent from which equal aliquots were drawn to form the mixtures was adj usted in concentration to provide for approximately equal reponse magn itudes. The magnitude of the taste responses to binary mixtures whose component amino acids showed minimal cross-adaptation was significantl y greater than that to binary mixtures whose components exhibited cons iderable cross-reactivity. There was no evidence for mixture suppressi on. The relative magnitude of the taste responses in the sea catfish t o stimulus mixtures is similar to that previously reported for olfacto ry receptor responses in the freshwater channel catfish and chorda tym pani taste responses in the hamster.