title: Regulation of voltage-gated K+ channels by glucose metabolism in pancreatic beta-cells.
abstract: Regulation of delayed rectifier-type K(+) channels (Kv-channels) by glucose was studied in rat pancreatic beta-cells. The Kv-channel current was increased in amplitudes by increasing glucose concentration from 2.8 to 16.6mM, while it was decreased by 2.8mM glucose in a reversible manner (down-regulation) in both perforated and conventional whole-cell modes. The current was decreased by FCCP, intrapipette 0mM ATP or AMPPNP. Glyceraldehyde, pyruvic acid, 2-ketoisocaproic acid, and 10mM MgATP prevented the down-regulation induced by 2.8mM or less glucose. The residual current after treatment with Kv2.1-specific blocker, guangxitoxin-1E, was unchanged by lowering or increasing glucose concentration. We conclude that glucose metabolism regulates Kv2.1 channels in rats beta-cells via altering MgATP levels.
authors.affiliation: First Department of Medicine, Saitama Medical Center, Jichi Medical University School of Medicine, Omiya 1-847, Saitama, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Yoshida
authors.forename: Katsuya
authors.initials: K
authors.lastname: Dezaki
authors.forename: Shiho
authors.initials: S
authors.lastname: Yamato
authors.forename: Atsushi
authors.initials: A
authors.lastname: Aoki
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Sugawara
authors.forename: Hideo
authors.initials: H
authors.lastname: Toyoshima
authors.forename: San-e
authors.initials: SE
authors.lastname: Ishikawa
authors.forename: Masanobu
authors.initials: M
authors.lastname: Kawakami
authors.forename: Masanori
authors.initials: M
authors.lastname: Nakata
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yada
authors.forename: Masafumi
authors.initials: M
authors.lastname: Kakei
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D015536:Down-Regulation; D005947:Glucose / Q000378:metabolism*; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D018408:Patch-Clamp Techniques; D024642:Potassium Channels, Voltage-Gated / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013696:Temperature
chemical_list: D024642:Potassium Channels, Voltage-Gated; D000255:Adenosine Triphosphate; D005947:Glucose