Activation of calcium-sensitive potassium channels in L6 skeletal myocytes by arginine vasopressin requires extracellular calcium

Gosling, Martin, Smith, J.W. and Poyner, David R. (1995). Activation of calcium-sensitive potassium channels in L6 skeletal myocytes by arginine vasopressin requires extracellular calcium. Biochemical and Biophysical Research Communications, 217 (3), pp. 1163-1168.

Abstract

The effects of extracellular application of arginine vasopressin (AVP) upon membrane currents in L6 skeletal myocytes was investigated using the whole-cell configuration of the patch-clamp technique. At O mV AVP produced large amplitude, transient outward currents that reversed when the clamping potential was changed to -100 mV (negative to EK) The effects of alterations in the extracellular K+ concentration upon the current reversal potential suggested that the current elicited by AVP was carried mainly by K+ ions. Intracellular dialysis with 10 μM inositol 1,4,5-trisphosphate (InsP3) elicited similar currents but only in 6/14 cells. Inclusion of 5 mg ml-1 heparin in the intracellular solutions was ineffective at inhibiting the current responses to AVP. The AVP-induced current was totally abolished when the intracellular EGTA concentration was increased from 0.05 mM to 10 mM or Ca2+ was removed from the extracellular perfusing solution. These results suggest that AVP produces activation of a Ca2+-sensitive K+ conductance in L6 skeletal myocytes by a process dependent upon extracellular Ca2+ and not intracellular Ca2+ release. © 1995 Academic Press. All rights reserved.

Publication DOI: https://doi.org/10.1006/bbrc.1995.2891
Divisions: Life & Health Sciences > Pharmacy
Life & Health Sciences
Uncontrolled Keywords: animals,arginine vasopressin calcium cells,cultured chelating agents,egtazic acid,extracellular epace membrane potentials,muscles,patch-clamp techniques,potassium channels,rats,Molecular Biology,Cell Biology,Biophysics,Biochemistry
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Related URLs: http://www.scopus.com/inward/record.url?scp=0029610828&partnerID=8YFLogxK (Scopus URL)
Published Date: 1995-12-26
Authors: Gosling, Martin
Smith, J.W.
Poyner, David R. ( 0000-0003-1590-112X)

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