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Cellular and Molecular Neurobiology

, Volume 13, Issue 1, pp 59–68 | Cite as

Dendrotoxin blocks a class of potassium channels that are opened by inhibitory presynaptic modulators in rat cortical synaptosomes and slices

  • Gabor Zoltay
  • Jack R. Cooper
Article

Summary

  1. 1.

    Rat cortical synaptosomes were prelabeled with radioactive acetylcholine and the release induced by veratridine was determined in the absence and presence of the inhibitory presynaptic modulators, 2-chloroadenosine, carbamylcholine, clonidine, and morphine. All four agents inhibited the evoked release of acetylcholine and this inhibition was reversed by dendrotoxin.

     
  2. 2.

    Using perfused cortical slices and an extracellular K-sensitive electrode, all modulators again increased K efflux that was blocked by dendrotoxin. In contrast, glybenclamide and tetraethylammonium did not block the modulatorinduced efflux.

     

Key words

Dendrotoxin 2-chloroadenosine carbamylcholine morphine clonidine K channels presynaptic modulation 

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Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • Gabor Zoltay
    • 1
  • Jack R. Cooper
    • 1
  1. 1.Department of PharmacologyYale University School of MedicineNew HavenUSA

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