Swelling-activated potassium channel in porcine pigmented ciliary epithelial cells.

• Takahira, Masayuki

• Sakurai, Mayumi

• Sakurada, Norimasa

• Sugiyama, Kazuhisa

抄録

Ion channels in the ciliary epithelium play critical roles in the formation of aqueous humor in the eye. The present study identified a novel, swelling-activated K(+) current in freshly dissociated porcine pigmented ciliary epithelial cells. Ciliary epithelial cells were freshly dissociated from porcine eyes. Whole-cell currents were recorded by the patch-clamp technique in pigmented and nonpigmented ciliary epithelial cell (PCE-NPCE) pairs or single PCE cells. The 0-current potential was -49 ± 13 mV in PCE-NPCE cell pairs (n = 97) and -52 ± 12 mV in single PCE cells (n = 30). Whole-cell currents in these cells were dominated by an outwardly rectifying K(+) current activated by potentials more positive than -90 mV, which never inactivated during prolonged depolarization. The K(+) current was significantly augmented by hypotonic cell perfusion. External Ba(2+) was a blocker of this K(+) conductance (IC(50) of 0.38 mM), but the conductance was insensitive to external TEA(+). Linopirdine, a specific inhibitor of KCNQ channels, effectively blocked the K(+) current in these PCE cells. Porcine PCE cells express a swelling-activated K(+) channel, which may be a member of the KCNQ/Kv7 channel family. This K(+) channel is active near resting potentials and could contribute to the regulation of cell volume and water transport via the ciliary epithelia.

収録刊行物

• Investigative ophthalmology & visual science

  Investigative ophthalmology & visual science 52 (8), 5928-5932, 2011-07-01

  Association for Research in Vision and Ophthalmology (ARVO)

詳細情報

• CRID: 1050282810960580864
• NII論文ID: 120003479729
• ISSN: 15525783
• Web Site: http://hdl.handle.net/2297/29471
• 本文言語コード: en
• 資料種別: journal article
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  • CiNii Articles