Identification of native rat cerebellar granule cell currents due to background K channel KCNK5 (TASK-2)

被引:15
作者
Cotten, JF [1 ]
Zou, HL [1 ]
Liu, CH [1 ]
Au, JD [1 ]
Yost, CS [1 ]
机构
[1] Univ Calif San Francisco, Dept Anesthesia & Perioperat Care, San Francisco, CA 94143 USA
来源
MOLECULAR BRAIN RESEARCH | 2004年 / 128卷 / 02期
关键词
background potassium channels; tandem pore; cerebellar granule cells;
D O I
10.1016/j.molbrainres.2004.06.007
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
The TWIK-related, Acid Sensing K (TASK-2; KCNK5) potassium channel is a member of the tandem pore (2P) family of potassium channels and mediates an alkaline pH-activated, acid pH-inhibited, outward-rectified potassium conductance. In previous work, we demonstrated TASK-2 protein expression in newborn rat cerebellar granule neurons (CGNs). In this study, we demonstrate TASK-2 functional expression in CGNs as a component of the pH-sensitive, volatile anesthetic-potentiated, standing-outward potassium conductance (I-K,I-SO). Using excised, inside-out patch-clamp technique, we studied CGNs grown in primary culture. We identified four distinct, noninactivating single channel potassium conductances, Types 1-4. Types 1-3 have previously been attributed to TASK-1 (KCNK3), TASK-3 (KCNK9) and TASK-1/TASK-3 heteromers, and TREK-2 (KCNK10) 2P potassium channel function, respectively; however, the Type 4 conductance is currently unassigned. Previous studies demonstrated that Type 4 single channel activity is potentiated by extracellular, alkaline pH and cytoplasmic arachidonic acid (10-20 muM) and inhibited by cytoplasmic tetraethyl ammonium (TEA; 1 mM). We determined that heterologously expressed TASK-2 channels have single channel gating, conductance properties and pH sensitivity identical to the Type 4 conductance. Additionally, we found that TASK-2 single channel activity, like the Type 4 conductance is potentiated by cytoplasmic arachidonic acid (20 muM) and inhibited by cytoplasmic TEA (1 mM). We conclude that TASK-2 mediates the Type 4 single channel conductance in CGNs as a component of I-K,I-SO. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:112 / 120
页数:9
相关论文
共 53 条
[1]   Adaptive regulation of neuronal excitability by a voltage-independent potassium conductance [J].
Brickley, SG ;
Revilla, V ;
Cull-Candy, SG ;
Wisden, W ;
Farrant, M .
NATURE, 2001, 409 (6816) :88-92
[2]   DIRECT MODULATION OF APLYSIA S-K+ CHANNELS BY A 12-LIPOXYGENASE METABOLITE OF ARACHIDONIC-ACID [J].
BUTTNER, N ;
SIEGELBAUM, SA ;
VOLTERRA, A .
NATURE, 1989, 342 (6249) :553-555
[3]   Inhibition of TASK-1 potassium channel by phospholipase C [J].
Czirják, G ;
Petheo, GL ;
Spät, A ;
Enyedi, P .
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 2001, 281 (02) :C700-C708
[4]   TASK, a human background K+ channel to sense external pH variations near physiological pH [J].
Duprat, F ;
Lesage, F ;
Fink, M ;
Reyes, R ;
Heurteaux, C ;
Lazdunski, M .
EMBO JOURNAL, 1997, 16 (17) :5464-5471
[5]   γ-hydroxybutyric acid and diazepam antagonize a rapid increase in GABAA receptors α4 subunit mRNA abundance induced by ethanol withdrawal in cerebellar granule cells [J].
Follesa, P ;
Mancuso, L ;
Biggio, F ;
Mostallino, MC ;
Manca, A ;
Mascia, MP ;
Busonero, F ;
Talani, G ;
Sanna, E ;
Biggio, G .
MOLECULAR PHARMACOLOGY, 2003, 63 (04) :896-907
[6]   Localization of the tandem pore domain K+ channel KCNK5 (TASK-2) in the rat central nervous system [J].
Gabriel, A ;
Abdallah, M ;
Yost, CS ;
Winegar, BD ;
Kindler, CH .
MOLECULAR BRAIN RESEARCH, 2002, 98 (1-2) :153-163
[7]  
GALLO V, 1987, J NEUROSCI, V7, P2203
[8]   Mutation of KCNK5 or kir3.2 potassium channels in mice does not change minimum alveolar anesthetic concentration [J].
Gerstin, KM ;
Gong, DH ;
Abdallah, M ;
Winegar, BD ;
Eger, EI ;
Gray, AT .
ANESTHESIA AND ANALGESIA, 2003, 96 (05) :1345-1349
[9]   Genomic and functional characteristics of novel human pancreatic 2P domain K+ channels [J].
Girard, C ;
Duprat, F ;
Terrenoire, C ;
Tinel, N ;
Fosset, M ;
Romey, G ;
Lazdunski, M ;
Lesage, F .
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 2001, 282 (01) :249-256
[10]   Potassium leak channels and the KCNK family of two-P-domain subunits [J].
Goldstein, SAN ;
Bockenhauer, D ;
O'Kelly, I ;
Zilberberg, N .
NATURE REVIEWS NEUROSCIENCE, 2001, 2 (03) :175-184