Enhancement of the Shaker B delta6-46 current by fatty acids depends on the activation of the lipoxygenase metabolic pathway.
Voltage-gated K+ channels are modulated by extracellular free unsaturated fatty acids. Both increases and attenuations of K+ channels activities have been observed. We studied the effect of cis-unsaturated fatty acids on Shaker B delta6-46 and the endogenous outward rectifier K+ channels expressed in COS cell line, using the whole cell recording technique. For both K+ channels, exogenously applied unsaturated fatty acids dramatically increased the outward K+ currents. This enhancement was not mediated by cylooxygenase or epoxygenase (P450) enzymes. However, nordihydroguaiaretic acid, a lipoxygenase metabolic pathway blocker, did prevent the arachidonic acid-induced Shaker current enhancement.
Bendahhou
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Departments of Physiology and Neuroscience, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA.
Agnew
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WS
D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism / Q000494:pharmacology; D019556:COS Cells; D004553:Electric Conductivity; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D008084:Lipoxygenase / Q000378:metabolism*; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D009637:Masoprocol / Q000494:pharmacology; D015221:Potassium Channels / Q000187:drug effects* / Q000502:physiology*; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology
D005231:Fatty Acids, Unsaturated; D016859:Lipoxygenase Inhibitors; D015221:Potassium Channels; D013757:Tetraethylammonium Compounds; D016718:Arachidonic Acid; D019789:Tetraethylammonium; D009637:Masoprocol; D008084:Lipoxygenase