Electrophysiological characterization of a new member of the RCK family of rat brain K+ channels.
A novel member of the RCK family of rat brain K+ channels, called RCK2, has been sequenced and expressed in Xenopus oocytes. The K+ currents were voltage-dependent, activated within 20 ms (at 0 mV), did not inactivate in 5 s, and had a single channel conductance in frog Ringers of 8.2 pS. Compared to other members of the RCK family the pharmacological profile of RCK2 was unique in that the channel was resistant to block (IC50 = 3.3 microM) by charybdotoxin [(1988) Proc. Natl. Acad. Sci. USA 85, 3329-3333] but relatively sensitive to 4-aminopyridine (0.3 mM), tetraethylammonium (1.7 mM), alpha-dendrotoxin (25 nM), noxiustoxin (200 nM), and mast cell degranulating peptide (200 nM). Thus, RCK2 is a non-inactivating delayed rectifier K+ channel with interesting pharmacological properties.
Kirsch
G E
GE
Department of Anesthesiology, Baylor College of Medicine, Houston, TX 77030.
Drewe
J A
JA
Verma
S
S
Brown
A M
AM
Joho
R H
RH
D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000502:physiology*; D004247:DNA / Q000235:genetics; D051662:Kv1.1 Potassium Channel; D051667:Kv1.6 Potassium Channel; D008564:Membrane Potentials; D008565:Membrane Proteins / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D015221:Potassium Channels / Q000235:genetics* / Q000502:physiology; D024642:Potassium Channels, Voltage-Gated; D051381:Rats; D014981:Xenopus / Q000235:genetics
C489293:Kcna1 protein, rat; C064390:Kcna6 protein, rat; D051667:Kv1.6 Potassium Channel; D008565:Membrane Proteins; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D051662:Kv1.1 Potassium Channel; D004247:DNA