Identification of the Kv2.1 K+ channel as a major component of the delayed rectifier K+ current in rat hippocampal neurons

Hideyuki Murakoshi, James Trimmer

Research output: Contribution to journalArticle

228 Scopus citations

Abstract

Molecular cloning studies have revealed the existence of a large family of voltage-gated K+ channel genes expressed in mammalian brain. This molecular diversity underlies the vast repertoire of neuronal K+ channels that regulate action potential conduction and neurotransmitter release and that are essential to the control of neuronal excitability. However, the specific contribution of individual K+ channel gene products to these neuronal K+ currents is poorly understood. We have shown previously, using an antibody, 'KC,' specific for the Kv2.1 K+ channel α-subunit, the high- level expression of Kv2.1 protein in hippocampal neurons in situ and in culture. Here we show that KC is a potent blocker of K+ currents expressed in cells transfected with the Kv2.1 cDNA, but not of currents expressed in cells transfected with other highly related K+ channel α-subunit cDNAs. KC also blocks the majority of the slowly inactivating outward current in cultured hippocampal neurons, although antibodies to two other K+ channel α-subunits known to be expressed in these cells did not exhibit blocking effects. In all cases the blocking effects of KC were eliminated by previous incubation with a recombinant fusion protein containing the KC antigenic sequence. Together these studies show that Kv2.1, which is expressed at high levels in most mammalian central neurons, is a major contributor to the delayed rectifier K+ current in hippocampal neurons and that the KC antibody is a powerful tool for the elucidation of the role of the Kv2.1 K+ channel in regulating neuronal excitability.

Original languageEnglish (US)
Pages (from-to)1728-1735
Number of pages8
JournalJournal of Neuroscience
Volume19
Issue number5
StatePublished - Mar 1 1999
Externally publishedYes

Keywords

  • CNS
  • Epilepsy
  • Hippocampus
  • Immunofluorescence
  • Ion channel
  • Neuronal excitability
  • Patch clamp
  • Potassium current

ASJC Scopus subject areas

  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Identification of the Kv2.1 K<sup>+</sup> channel as a major component of the delayed rectifier K<sup>+</sup> current in rat hippocampal neurons'. Together they form a unique fingerprint.

  • Cite this