Abstract
The neutral noncyclic imide and ether containing ionophore (AS701), a selective carrier for Li+ among alkali cations, was found to be capable of mediating the transport of NH4+ and of biogenic amines (catechols and indoles) across lipid bilayer membranes also. Ionophore-mediated electrical properties of planar lipid bilayers were studied under experimental conditions where the positively-charged amine species was dominant. The ionophore was found to act as a selective carrier of the biogenic amines, mediating their electrogenic transport across the membrane, forming 2:1 carrier-amine permeant complexes, carrying a net-charge of +1. Selectively among the amines corresponding to the following sequence: tryptamine (35) > Li+ (1) > serotonin (0.60) > dopamine (0.19) > norepinephrine (0.13) > epinephrine (0.05) > NH4+ (0.05). The molecular factors involved in determining these selectivities are assessed.
Original language | English |
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Pages (from-to) | 193-198 |
Number of pages | 6 |
Journal | BBA - Biomembranes |
Volume | 774 |
Issue number | 2 |
DOIs | |
State | Published - 25 Jul 1984 |
Keywords
- (Lipid bilayer)
- Biogenic amine
- Electrogenic transport
- Ionophore AS701