Abstract
Only some taste cells fire action potentials in response to sapid stimuli. Type II taste cells express many taste transduction molecules but lack well-elaborated synapses, bringing into question the functional significance of action potentials in these cells. We examined the dependence of adenosine triphosphate (ATP) transmitter release from taste cells on action potentials. To identify type II taste cells we used mice expressing a green fluorescence protein (GFP) transgene from the α-gustducin promoter. Action potentials were recorded by an electrode basolaterally attached to a single GFP-positive taste cell. We monitored ATP release from gustducin-expressing taste cells by collecting the electrode solution immediately after tastant-stimulated action potentials and using a luciferase assay to quantify ATP. Stimulation of gustducin-expressing taste cells with saccharin, quinine, or glutamate on the apical membrane increased ATP levels in the electrode solution; the amount of ATP depended on the firing rate. Increased spontaneous firing rates also induced ATP release from gustducin-expressing taste cells. ATP release from gustducin-expressing taste cells was depressed by tetrodotoxin and inhibited below the detection limit by carbenoxolone. Our data support the hypothesis that action potentials in taste cells responsive to sweet, bitter, or umami tastants enhance ATP release through pannexin 1, not connexin-based hemichannels.
| Original language | English |
|---|---|
| Pages (from-to) | 896-901 |
| Number of pages | 6 |
| Journal | Journal of Neurophysiology |
| Volume | 104 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Aug 1 2010 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Neuroscience(all)
- Physiology
Cite this
Action potential-enhanced ATP release from taste cells through hemichannels. / Murata, Yoshihiro; Yasuo, Toshiaki; Yoshida, Ryusuke; Obata, Kunihiko; Yanagawa, Yuchio; Margolskee, Robert F.; Ninomiya, Yuzo.
In: Journal of Neurophysiology, Vol. 104, No. 2, 01.08.2010, p. 896-901.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Action potential-enhanced ATP release from taste cells through hemichannels
AU - Murata, Yoshihiro
AU - Yasuo, Toshiaki
AU - Yoshida, Ryusuke
AU - Obata, Kunihiko
AU - Yanagawa, Yuchio
AU - Margolskee, Robert F.
AU - Ninomiya, Yuzo
PY - 2010/8/1
Y1 - 2010/8/1
N2 - Only some taste cells fire action potentials in response to sapid stimuli. Type II taste cells express many taste transduction molecules but lack well-elaborated synapses, bringing into question the functional significance of action potentials in these cells. We examined the dependence of adenosine triphosphate (ATP) transmitter release from taste cells on action potentials. To identify type II taste cells we used mice expressing a green fluorescence protein (GFP) transgene from the α-gustducin promoter. Action potentials were recorded by an electrode basolaterally attached to a single GFP-positive taste cell. We monitored ATP release from gustducin-expressing taste cells by collecting the electrode solution immediately after tastant-stimulated action potentials and using a luciferase assay to quantify ATP. Stimulation of gustducin-expressing taste cells with saccharin, quinine, or glutamate on the apical membrane increased ATP levels in the electrode solution; the amount of ATP depended on the firing rate. Increased spontaneous firing rates also induced ATP release from gustducin-expressing taste cells. ATP release from gustducin-expressing taste cells was depressed by tetrodotoxin and inhibited below the detection limit by carbenoxolone. Our data support the hypothesis that action potentials in taste cells responsive to sweet, bitter, or umami tastants enhance ATP release through pannexin 1, not connexin-based hemichannels.
AB - Only some taste cells fire action potentials in response to sapid stimuli. Type II taste cells express many taste transduction molecules but lack well-elaborated synapses, bringing into question the functional significance of action potentials in these cells. We examined the dependence of adenosine triphosphate (ATP) transmitter release from taste cells on action potentials. To identify type II taste cells we used mice expressing a green fluorescence protein (GFP) transgene from the α-gustducin promoter. Action potentials were recorded by an electrode basolaterally attached to a single GFP-positive taste cell. We monitored ATP release from gustducin-expressing taste cells by collecting the electrode solution immediately after tastant-stimulated action potentials and using a luciferase assay to quantify ATP. Stimulation of gustducin-expressing taste cells with saccharin, quinine, or glutamate on the apical membrane increased ATP levels in the electrode solution; the amount of ATP depended on the firing rate. Increased spontaneous firing rates also induced ATP release from gustducin-expressing taste cells. ATP release from gustducin-expressing taste cells was depressed by tetrodotoxin and inhibited below the detection limit by carbenoxolone. Our data support the hypothesis that action potentials in taste cells responsive to sweet, bitter, or umami tastants enhance ATP release through pannexin 1, not connexin-based hemichannels.
UR - http://www.scopus.com/inward/record.url?scp=77955929155&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77955929155&partnerID=8YFLogxK
U2 - 10.1152/jn.00414.2010
DO - 10.1152/jn.00414.2010
M3 - Article
C2 - 20519578
AN - SCOPUS:77955929155
VL - 104
SP - 896
EP - 901
JO - Journal of Neurophysiology
JF - Journal of Neurophysiology
SN - 0022-3077
IS - 2
ER -