Effects of Aliphatic Alcohols and Aldehydes on Fluidity of Spin-Labeled Synaptosomal Plasma Membranes

  • Jane H. Chin
  • Dora B. Goldstein

Abstract

Synaptosomal plasma membranes from Swiss-Webster mice were spin-labeled with 5-doxylstearic acid. By electron paramagnetic resonance techniques an order parameter was measured. A decrease in the order parameter reflected an increase in membrane fluidity. In confirmation of our previous work, ethanol decreased membrane order. Pentanol also showed a concentration-related decrease in the order parameter in the range of 23 to 87 mM. At equimolar concentrations, pentanol was about 9 times more effective than ethanol. Acetaldehyde had no effect on membrane fluidity at concentrations that might be found in vivo during ethanol oxidation (23 or 227 μM) but a very high concentration, 2.3 mM, produced a small decrease in the order parameter comparable to the effect of an intoxicating concentration of ethanol. Valeraldehyde also had a slight fluidizing effect and appeared very roughly three times more potent than acetaldehyde. This study shows that the fluidizing effects of ethanol are not shared by its aldehyde metabolite at relevant concentrations. The fluidizing effects of aldehydes are slight but they increase with concentration and with chain length.

We previously showed by a sensitive electron paramagnetic resonance (EPR) technique that low concentrations of ethanol increased the fluidity of mouse erythrocyte and synaptosomal plasma membranes (Chin and Goldstein, 1977a,b) and that tolerance developed to this effect (Chin and Goldstein, 1977c). However, some of the acute and chronic effects of ethanol have been attributed to its primary metabolite, acetaldehyde, which is thought to act either alone or after combining with biogenic amines to form tetrahydroisoquinolines (Cohen, 1976). In the present study we have compared the membrane action of acetaldehyde to those of ethanol, using concentrations that circulate in vivo during ethanol oxidation. Pentanol and valeraldehyde were also tested, to assess the influence of chain length.

Keywords

Electron Paramagnetic Resonance Biogenic Amine Membrane Fluidity Aliphatic Alcohol Ethanol Oxidation 
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References

  1. Beer, C. T. and Quastel, J. H., 1958a, The effects of aliphatic aldehydes on the respiration of rat brain cortex slices and rat brain mitochondria, Canad. J. Biochem. Physiol., 36: 531–541.Google Scholar
  2. Beer, C. T. and Quastel, J. H., 1958b, The effects of aliphatic alcohols on the respiration of rat brain cortex slices and rat brain mitochondria, Canad. J. Biochem. Physiol., 36: 543–556.Google Scholar
  3. Chin, J. H. and Goldstein, D. B., 1977a, Electron paramagnetic resonance studies of ethanol on membrane fluidity, in: “Alcohol Intoxication and Withdrawal-Ilia”, Biological aspects of ethanol, pp. 111–122, M. M. Gross, ed., Plenum Press, New York.Google Scholar
  4. Chin, J. H. and Goldstein, D. B., 1977b, Effects of low concentrations of ethanol on the fluidity of spin-labeled erythrocyte and brain membranes, Molec. Pharmacol., 13: 435–441.Google Scholar
  5. Chin, J. H. and Goldstein, D. B., 1977c, Drug tolerance in biomembranes: A spin label study of the effects of ethanol, Science, 196: 684–685.Google Scholar
  6. Cohen, G., 1976, Alkaloid products in the metabolism of alcohol and biogenic amines, Biochem. Pharmacol., 25: 1123–1128.Google Scholar
  7. Gaffney, B. J., 1976, Practical considerations for the calculation of order parameters for fatty acid or phospholipid spin labels in membranes, in: “Spin Labeling, Theory and Applications”, pp. 567–571, L. J. Berliner, ed., Academic Press, New York.Google Scholar
  8. Hubbell, W. L. and McConnell, H. M., 1971, Molecular motion in spin labeled phospholipids and membranes, J. Amer. Chem. Soc., 93: 314–326.Google Scholar
  9. Leo, A., Hansch, C., and Elkins, D., 1971, Partition coefficients and their uses, Chemical Reviews, 71: 525–616.CrossRefGoogle Scholar
  10. Lindros, K. O., 1978, Acetaldehyde-Its metabolism and role in the actions of alcohol, in: “Research Advances in Alcohol and Drug Problems”, R.G. Smart, et al., eds., Plenum Press, New York.Google Scholar

Copyright information

© Springer Science+Business Media New York 1980

Authors and Affiliations

  • Jane H. Chin
    • 1
  • Dora B. Goldstein
    • 1
  1. 1.Department of PharmacologyStanford University School of MedicineStanfordUSA

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