TY - JOUR T1 - GABA, Its Receptors, and GABAergic Inhibition in Mouse Taste Buds JF - The Journal of Neuroscience JO - J. Neurosci. SP - 5782 LP - 5791 DO - 10.1523/JNEUROSCI.5559-10.2011 VL - 31 IS - 15 AU - Gennady Dvoryanchikov AU - Yijen A. Huang AU - Rene Barro-Soria AU - Nirupa Chaudhari AU - Stephen D. Roper Y1 - 2011/04/13 UR - http://www.jneurosci.org/content/31/15/5782.abstract N2 - Taste buds consist of at least three principal cell types that have different functions in processing gustatory signals: glial-like (type I) cells, receptor (type II) cells, and presynaptic (type III) cells. Using a combination of Ca2+ imaging, single-cell reverse transcriptase-PCR and immunostaining, we show that GABA is an inhibitory transmitter in mouse taste buds, acting on GABAA and GABAB receptors to suppress transmitter (ATP) secretion from receptor cells during taste stimulation. Specifically, receptor cells express GABAA receptor subunits β2, δ, and π, as well as GABAB receptors. In contrast, presynaptic cells express the GABAA β3 subunit and only occasionally GABAB receptors. In keeping with the distinct expression pattern of GABA receptors in presynaptic cells, we detected no GABAergic suppression of transmitter release from presynaptic cells. We suggest that GABA may serve function(s) in taste buds in addition to synaptic inhibition. Finally, we also defined the source of GABA in taste buds: GABA is synthesized by GAD65 in type I taste cells as well as by GAD67 in presynaptic (type III) taste cells and is stored in both those two cell types. We conclude that GABA is an inhibitory transmitter released during taste stimulation and possibly also during growth and differentiation of taste buds. ER -