Effect of the general anesthetic halothane on the activity of the transverse tubule Ca(2+)-activated K+ channel.
The effect of the general anesthetic halothane on the activity of the rat skeletal muscle Ca(2+)-activated K+ channel in planar lipid bilayers was investigated. Halothane concentrations in the clinical range (1.0-0.2 mM) alter the regulation of the channel by both Ca2+ and membrane potential. At Ca2+ concentrations between 10 and 250 microM and membrane potentials between 0 and -30 mV, halothane significantly decreases the open state probability without changing the channel conductance. The results demonstrate that halothane can act directly on the Ca(2+)-activated K+ channel or its lipid environment to alter the channel gating kinetics.
Beeler
T
T
Department of Biochemistry, Uniformed Services University of the Health Sciences, Bethesda, MD 20014.
Gable
K
K
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D006221:Halothane / Q000494:pharmacology*; D066298:In Vitro Techniques; D015640:Ion Channel Gating / Q000187:drug effects; D008564:Membrane Potentials / Q000187:drug effects; D008567:Membranes, Artificial; D009132:Muscles / Q000187:drug effects*; D015221:Potassium Channels / Q000187:drug effects*; D051381:Rats
D008567:Membranes, Artificial; D015221:Potassium Channels; D002118:Calcium; D006221:Halothane