Analytical Sciences
Online ISSN : 1348-2246
Print ISSN : 0910-6340
ISSN-L : 0910-6340
Original Papers
Arachidonic Acid-Induced Channel- and Carrier-Type Ion Transport across Planar Bilayer Lipid Membranes
Ayumi HIRANOYuko NAMATAMEEiichi WAKAIZUMIYuka MATSUNOMasao SUGAWARA
Author information
JOURNAL FREE ACCESS

2003 Volume 19 Issue 2 Pages 191-197

Details
Abstract

Transmembrane ion transport by arachidonic acid (AA) through bilayer lipid membranes (BLMs) was investigated by means of electrochemical measurements to provide a basis for designing a sensor membrane. We found that AA induces a channel-type current, in addition to a carrier-type current, across planar BLMs. A linear relation between the logarithmic value of the AA concentration and the current responses (given as integrated currents) was observed for a carrier-type current, while a sigmoid relation was found for a channel-type current. Although AA transports NA+, Ca2+ and Mg2+ and exhibits ion selectivity between Na+ and Mg2+ for the carrier-type current, ion transport for the channel-type current was non-selective. It was found that ion transport via the channel mechanism occurs frequently for AA, while channel-type currents were only occasionally observed for γ-linolenic acid and prostaglandin D2. No channel-type currents were induced by other fatty acids (oleic, linoleic, stearic, myristic, eicosapentanoic and docosahexanoic acids) and metabolites of AA (12-HETE and 5-HETE). The carrier-type ion transport occurs selectively to these compounds if the concentration is below 1.0 μM. These results suggest that AA selectively facilitates an ion flux through the BLMs, generating channel-type and/or carrier-type currents, which can be used as a measure of the AA concentration.

Content from these authors
© 2003 by The Japan Society for Analytical Chemistry
Next article
feedback
Top