Neurophysiology

, Volume 19, Issue 3, pp 265–269 | Cite as

Blocking action of calmidazolium and chlorpromazine on outward potassium current dependent on extra-cellular calcium ions

  • A. E. Martynyuk
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Abstract

The effects of the calmodulin antagonists, calmidazolium (R 24571) and chlorpromazine on delayed outward potassium current at the somatic membrane were investigated in non-identified intracellularly perfused neurons isolated fromHelix pomatia. Voltage was clamped at the membrane. Extracellular application of these substances produced effective depression of the outward current. This effect even occurred at test substance concentrations of 10−9–10−8 M. Block-ade of delayed outward current was produced mainly as a result of suppressing the potassium current component dependent on intracellular potassium ions (Ik(Ca/in)). The possibility that the receptor for intracellular calcium responsible for modulating this current may be of a calmodulin-like nature is discussed.

Keywords

Calcium Potassium Substance Concentration Intracellular Calcium Chlorpromazine 
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Copyright information

© Plenum Publishing Corporation 1988

Authors and Affiliations

  • A. E. Martynyuk

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