Calcium-Activated Potassium Channels in Bullfrog Sympathetic Ganglion Cells

  • Paul R. Adams
  • David A. Brown
  • Andrew Constanti
  • Robert B. Clark
  • Leslie Satin


The existence of a calcium activated potassium current (Ic) in the somata of vertebrate sympathetic ganglion cells was postulated to account for the calcium-sensitive spike after-hyperpolarizations present in these cells [19,22,26]. We have studied Ic in bullfrog ganglion cells more directly by using various voltage-clamp techniques, partly in order to understand better the role this current plays in spike repolarization, spike afterhyperpolarization, and spontaneous hyperpolarizations, and partly to define the difference between Ic and the M-current Im [4]. Both Ic and Im are voltage-sensitive potassium currents sensitive to transmitters, the former being activated by internal calcium and the latter inactivated by external acetylcholine. Despite these superficial similarities, it turns out that the two currents have virtually nothing in common.


Ganglion Cell Outward Current Relaxation Time Constant Internal Calcium Dorsal Root Ganglion Cell 
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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • Paul R. Adams
    • 1
  • David A. Brown
    • 2
  • Andrew Constanti
    • 2
  • Robert B. Clark
    • 3
  • Leslie Satin
    • 1
  1. 1.Department of Neurobiology and BehaviorState University of New YorkStony BrookUSA
  2. 2.Department of PharmacologySchool of PharmacologyLondonEngland
  3. 3.Department of Physiology and BiophysicsUniversity of Texas Medical BranchGalvestonUSA

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