Huang, YA, Pereira, E and Roper, S (2011) Acid stimulation (sour taste) elicits GABA and serotonin release from mouse taste cells. PLoS one, 6 (10). e25471. ISSN 1932-6203

Abstract

Several transmitter candidates including serotonin (5-HT), ATP, andnorepinephrine (NE) have been identified in taste buds. Recently, gamma-aminobutyric acid(GABA) as well as the associated synthetic enzymes and receptors have also beenidentified in taste cells. GABA reduces taste-evoked ATP secretion from Receptor cellsand is considered to be an inhibitory transmitter in taste buds. However, to date, the
identity of GABAergic taste cells and the specific stimulus for GABA release are not wellunderstood. In the present study, we used genetically-engineered Chinese hamsterovary (CHO) cells stably co-expressing GABAB receptors and G alpha qo5 proteins tomeasure GABA release from isolated taste buds. We recorded robust responses fromGABA biosensors when they were positioned against taste buds isolated from mouse
circumvallate papillae and the buds were depolarized with KCl or a stimulated with anacid (sour) taste. In contrast, a mixture of sweet and bitter taste stimuli did not trigger
GABA release. KCl- or acid-evoked GABA secretion from taste buds was Ca2+-dependent; removing Ca2+ from the bathing medium eliminated GABA secretion.Finally, we isolated individual taste cells to identify the origin of GABA secretion. GABAas released only from Presynaptic (Type III) cells and not from Receptor (Type II)cells. Previously, we reported that 5-HT released from Presynaptic cells inhibits tasteevokedATP secretion. Combined with the recent findings that GABA depresses tasteevokedATP secretion [1], the present results indicate that GABA and 5-HT areinhibitory transmitters in mouse taste buds and both likely play an important role inmodulating taste responses.

Item Type:	Article
Date Deposited:	26 Apr 2016 23:46
Last Modified:	26 Apr 2016 23:46
URI:	https://oak.novartis.com/id/eprint/6005