Abstract
Acid-sensing ion channels (ASICs) regulate synaptic activities and play important roles in neurodegenerative diseases. They are highly expressed in the striatum, where medium spiny neurons (MSNs) are a major population. Given that the properties of ASICs in MSNs are unknown, in this study, we characterized ASICs in MSNs of the mouse striatum. A rapid drop in extracellular pH induced transient inward currents in all MSNs. The pH value for half-maximal activation was 6.25, close to that obtained in homomeric ASIC1a channels. Based on psalmotoxin 1 and zinc sensitivity, ASIC1a (70.5% of neurons) and heteromeric ASIC1a-2 channels (29.5% of neurons) appeared responsible for the acid-induced currents in MSNs. ASIC currents were diminished in MSNs from ASIC1, but not ASIC2, null mice. Furthermore, a drop in pH induced calcium influx by activating homomeric ASIC1a channels. Activation of ASICs increased the membrane excitability of MSNs and lowering extracellular Ca2+ potentiated ASIC currents. Our data suggest that the homomeric ASIC1a channel represents a majority of the ASIC isoform in MSNs. The potential function of ASICs in the striatum requires further investigation.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 55-66 |
| Number of pages | 12 |
| Journal | Neuroscience |
| Volume | 162 |
| Issue number | 1 |
| DOIs | |
| State | Published - Aug 4 2009 |
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Keywords
- acid-sensing ion channels
- calcium imaging
- medium spiny neurons
- membrane excitability
- patch-clamp
- striatum
ASJC Scopus subject areas
- Neuroscience(all)
Cite this
Characterization of acid-sensing ion channels in medium spiny neurons of mouse striatum. / Jiang, Q.; Li, Minghua; Papasian, C. J.; Branigan, D.; Xiong, Z. G.; Wang, J. Q.; Chu, X. P.
In: Neuroscience, Vol. 162, No. 1, 04.08.2009, p. 55-66.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Characterization of acid-sensing ion channels in medium spiny neurons of mouse striatum
AU - Jiang, Q.
AU - Li, Minghua
AU - Papasian, C. J.
AU - Branigan, D.
AU - Xiong, Z. G.
AU - Wang, J. Q.
AU - Chu, X. P.
PY - 2009/8/4
Y1 - 2009/8/4
N2 - Acid-sensing ion channels (ASICs) regulate synaptic activities and play important roles in neurodegenerative diseases. They are highly expressed in the striatum, where medium spiny neurons (MSNs) are a major population. Given that the properties of ASICs in MSNs are unknown, in this study, we characterized ASICs in MSNs of the mouse striatum. A rapid drop in extracellular pH induced transient inward currents in all MSNs. The pH value for half-maximal activation was 6.25, close to that obtained in homomeric ASIC1a channels. Based on psalmotoxin 1 and zinc sensitivity, ASIC1a (70.5% of neurons) and heteromeric ASIC1a-2 channels (29.5% of neurons) appeared responsible for the acid-induced currents in MSNs. ASIC currents were diminished in MSNs from ASIC1, but not ASIC2, null mice. Furthermore, a drop in pH induced calcium influx by activating homomeric ASIC1a channels. Activation of ASICs increased the membrane excitability of MSNs and lowering extracellular Ca2+ potentiated ASIC currents. Our data suggest that the homomeric ASIC1a channel represents a majority of the ASIC isoform in MSNs. The potential function of ASICs in the striatum requires further investigation.
AB - Acid-sensing ion channels (ASICs) regulate synaptic activities and play important roles in neurodegenerative diseases. They are highly expressed in the striatum, where medium spiny neurons (MSNs) are a major population. Given that the properties of ASICs in MSNs are unknown, in this study, we characterized ASICs in MSNs of the mouse striatum. A rapid drop in extracellular pH induced transient inward currents in all MSNs. The pH value for half-maximal activation was 6.25, close to that obtained in homomeric ASIC1a channels. Based on psalmotoxin 1 and zinc sensitivity, ASIC1a (70.5% of neurons) and heteromeric ASIC1a-2 channels (29.5% of neurons) appeared responsible for the acid-induced currents in MSNs. ASIC currents were diminished in MSNs from ASIC1, but not ASIC2, null mice. Furthermore, a drop in pH induced calcium influx by activating homomeric ASIC1a channels. Activation of ASICs increased the membrane excitability of MSNs and lowering extracellular Ca2+ potentiated ASIC currents. Our data suggest that the homomeric ASIC1a channel represents a majority of the ASIC isoform in MSNs. The potential function of ASICs in the striatum requires further investigation.
KW - acid-sensing ion channels
KW - calcium imaging
KW - medium spiny neurons
KW - membrane excitability
KW - patch-clamp
KW - striatum
UR - http://www.scopus.com/inward/record.url?scp=66049153158&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=66049153158&partnerID=8YFLogxK
U2 - 10.1016/j.neuroscience.2009.04.029
DO - 10.1016/j.neuroscience.2009.04.029
M3 - Article
C2 - 19376200
AN - SCOPUS:66049153158
VL - 162
SP - 55
EP - 66
JO - Neuroscience
JF - Neuroscience
SN - 0306-4522
IS - 1
ER -