|
||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
The Journal of General Physiology, Vol 81, 283-304, Copyright © 1983 by The Rockefeller University Press
ARTICLES |
J Brahm
Human red cell permeability to the homologous series of methanol, ethanol, n-propanol, n-butanol, and n-hexanol was determined in tracer efflux experiments by the continuous flow tube method, whose time resolution is 2-3 ms. Control experiments showed that unstirred layers in the cell suspension were less than 2 X 10(-4) cm, and that permeabilities less than or equal to 10(-2) cm s-1 can be determined with the method. Alcohol permeability varied with the chain length (25 degrees C): Pmeth 3.7 X 10(-3) cm s-1, Peth 2.1 X 10(-3) cm s-1, Pprop 6.5 X 10(-3) cm s-1, Pbut less than or equal to 61 X 10(-3) cm s-1, Phex 8.7 X 10(-3) cm s-1. The permeability for methanol, ethanol, and n- propanol was concentration independent (1-500 mM). The permeability to n-butanol and n-hexanol, however, increased above the upper limit of determination at alcohol concentrations of 100 and 25 mM, respectively. The activation energies for the permeability to methanol, n-propanol, and n-hexanol were similar, 50-63 kJ mol-1. Methanol permeability was not reduced by p-chloromercuribenzene sulfonate (PCMBS), thiourea, or phloretin, which inhibit transport of water or hydrophilic nonelectrolytes. It is concluded (a) that all the alcohols predominantly permeate the membrane lipid bilayer structure; (b) that both the distribution coefficient and the diffusion coefficient of the alcohols within the membrane determine the permeability, and (c) that the relative importance of the two factors varies with changes in the chain length.
This article has been cited by other articles:
![]() |
J. C. Mathai, S. Tristram-Nagle, J. F. Nagle, and M. L. Zeidel Structural Determinants of Water Permeability through the Lipid Membrane J. Gen. Physiol., December 31, 2007; 131(1): 69 - 76. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. V. Ly and M. L. Longo The Influence of Short-Chain Alcohols on Interfacial Tension, Mechanical Properties, Area/Molecule, and Permeability of Fluid Lipid Bilayers Biophys. J., August 1, 2004; 87(2): 1013 - 1033. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Covarrubias, T. B. Vyas, L. Escobar, and A. Wei Alcohols Inhibit a Cloned Potassium Channel at a Discrete Saturable Site J. Biol. Chem., August 18, 1995; 270(33): 19408 - 19416. [Abstract] [Full Text] [PDF] |
||||
|
|