Immunolocalization of the voltage-gated potassium channel Kv2.2 in GABAergic neurons in the basal forebrain of rats and mice

Authors

  • Tracey O. Hermanstyne,

    1. Department of Neural and Pain Sciences, University of Maryland, Baltimore, Maryland 21201
    2. Program in Neuroscience, University of Maryland, Baltimore, Maryland 21201
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  • Yoshitaka Kihira,

    1. Department of Neural and Pain Sciences, University of Maryland, Baltimore, Maryland 21201
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  • Kaori Misono,

    1. Department of Neural and Pain Sciences, University of Maryland, Baltimore, Maryland 21201
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  • Ashley Deitchler,

    1. Department of Neural and Pain Sciences, University of Maryland, Baltimore, Maryland 21201
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  • Yuchio Yanagawa,

    1. Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, Maebashi 371-8511, Japan
    2. Japan Science and Technology Agency, CREST, Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan
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  • Hiroaki Misonou

    Corresponding author
    1. Department of Neural and Pain Sciences, University of Maryland, Baltimore, Maryland 21201
    2. Program in Neuroscience, University of Maryland, Baltimore, Maryland 21201
    • Department of Neural and Pain Sciences, Dental School, 650 W. Baltimore St., Baltimore, MD 21201
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Abstract

The Kv2 voltage-gated potassium channels, Kv2.1 and Kv2.2, are important regulators of neuronal excitability in mammalian brain. It has been shown that Kv2.1 channels are expressed in virtually all neurons in the brain. However, the cellular localization of Kv2.2 has not been fully elucidated. In this article we report that Kv2.2 is highly expressed in a subset of neurons in the magnocellular preoptic nucleus (MCPO) and the horizontal limb of the diagonal band of Broca (HDB) of the basal forebrain complex, which are areas highly implicated in the regulation of cortical activity and the sleep/wake cycle. It has been shown that MCPO and HDB contain distinct populations of neurons that differ in their neurochemicals, cholinergic, glutamatergic, and gamma-aminobutyric acid (GABA)ergic neurons. Using specific immunolabeling and knockin mice in which green fluorescent protein (GFP) is expressed in GABAergic neurons, we found that Kv2.2 is abundantly expressed in a large subpopulation of the GABAergic neurons in the MCPO and HDB. These data offer Kv2.2 as a molecular target to study the role of the specific subpopulation of basal forebrain GABAergic neurons. J. Comp. Neurol. 518:4298–4310, 2010. © 2010 Wiley-Liss, Inc.

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