Tandem-pore K(+) channels display an uneven distribution in amphibian retina.
Previous studies in retinal glial (Müller) cells have suggested that the dominant membrane currents are mediated by K(+) inward-rectifier (Kir) channels. After blockade of inwardly (Kir) and outwardly (KD and BK) conducting channels, a large K(+) conductance remains, but its nature has not been determined. Tandem-pore K(+) channels are likely candidates for this potassium conductance and the purpose of the present study was to determine, using immunocytochemistry, whether Müller cells express TASK-1, TASK-2, TREK-1 and/or TREK-2 potassium channel subunits. The results reveal that retinal glial cells express TASK-1 and TASK-2 subunits, but not TREK-1 or TREK-2 subunits. Furthermore, the distribution of TASK subunits differs from that of Kir channels and may contribute to the potassium conductance of Müller cells.
Eaton
Misty J
MJ
CMBN, Department of Biochemistry, School of Medicine, Universidad Central del Caribe, Box 60-327, Bayamón, Puerto Rico 00960-6032.
Veh
Rüdiger W
RW
Makarov
Felix
F
Shuba
Yaroslav M
YM
Reichenbach
Andreas
A
Skatchkov
Serguei N
SN
D000818:Animals; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D007150:Immunohistochemistry; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009457:Neuroglia / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D015221:Potassium Channels / Q000378:metabolism; D024683:Potassium Channels, Tandem Pore Domain / Q000187:drug effects / Q000378:metabolism*; D011894:Rana pipiens; D012160:Retina / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
C503438:KCNK10 protein, human; D009419:Nerve Tissue Proteins; D015221:Potassium Channels; D024683:Potassium Channels, Tandem Pore Domain; C103742:potassium channel protein TREK-1; C420132:potassium channel subfamily K member 3; D011188:Potassium