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Calcium channel gating and modulation by transmitters depend on cellular compartmentalization

Nature Neuroscience volume 3, pages 670678 (2000) | Download Citation

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Abstract

Voltage-gated Ca2+ channels participate in dendritic integration, yet functional properties of Ca2+ channels and mechanisms of their modulation by neurotransmitters in dendrites are unknown. Here we report how pharmacologically identified Ca2+ channels behave in different neural compartments. Whole-cell and cell-attached patch-clamp recordings were made on both cell bodies and electrically isolated dendrites of sympathetic neurons. We found not only that Ca2+ channel populations differentially contribute to somatic and dendritic currents but also that families of Ca2+ channels display gating properties and neurotransmitter modulation that depend on channel compartmentalization. By comparison with their somatic counterparts, dendritic N-type Ca2+ currents were hypersensitive to neurotransmitters and G proteins. Single-channel analysis showed that dendrites express a unique N-type channel that has enhanced interaction with Gβγ. Thus Ca2+ channels in dendrites seem to be specialized elements with unique regulatory mechanisms.

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Acknowledgements

We thank M. Dayrell for technical assistance and G. Milligan for the gift of Gα-transducin, Gβ1 and Gγ2 cDNAs. This work was supported by The Wellcome Trust.

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  1. Wellcome Laboratory for Molecular Pharmacology, Department of Pharmacology, University College London, Gower Street,London WC1E 6BT UK

    • Patrick Delmas
    • , Fe C. Abogadie
    • , Noel J. Buckley
    •  & David A. Brown

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Correspondence to Patrick Delmas.

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https://doi.org/10.1038/76621

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