Effects of iron-induced lipid peroxidation and of acidosis on choline uptake by synaptosomes
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The effects of iron-induced lipid peroxidation and of lactic acidosis on [3H]choline uptake were investigated on crude synaptosomes prepared from rat cerebral cortices. Fe2+-induced lipid peroxidation as evidenced from the production of thiobarbituric acid reactives substances (TBARS) was correlated with a decrease in high-affinity choline uptake (HACU). Trolox C, a free radical scavenger, prevented both Fe2+-induced TBARS production and decrease in HACU. Lactic acidosis (pH 6.0 for 30 or 60 min) increased the TBARS production with concomitant decrease in HACU (−48%, −78%, respectively). The acidosis dependent decrease was not reversible following pH 7.4 readjustment after 60 min acidosis. It was not prevented by trolox C, although trolox C inhibited the acidosis-induced production of TBARS. The results suggest that the contribution of acidosis to peroxidative damages is probably of less importance in comparison to other cytotoxic mechanisms.
Key WordsAcidosis lipid peroxidation choline uptake synaptosomes
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- 12.Minotti, G., and Aust, S. D. 1989. The role iron in oxygen radical mediated lipid peroxidation. Chem.-Biol.-Inter. 71:1–19.Google Scholar
- 13.Burton, G. W., and Ingold, K. U. 1989. Autoxidation of biological molecules. I: The antioxidant activity of vitamin E and related chain-breaking phenolic antioxidants in vitro. J. Am. Chem. Soc. 103:6472–6477.Google Scholar
- 17.Rafalowska, U., Liu, G. J., and Floyd, R. A. 1989. Peroxidation induced changes in synaptosomal transport of dopamine and γ aminobutyric acid. Free. Radical Biol. Med. 6:485–492.Google Scholar
- 20.Demopoulos, H., Flamm, E., Seligman, M., Power, R., Pietronigro, D., and Ransohoff, J. 1977. Molecular pathology of lipids in CNS membranes. Pages 491–508, In Jöbsis, F. F. (eds): oxygen and physiological function. Dallas, Texas, Professional Information Library.Google Scholar
- 22.Siesjö, B. K., Agardh, C.-D., and Bengtsson, F. 1989. Free radicals and brain damage. Cerebrovasc. Brain Metab. Rev. 1:165–211.Google Scholar
- 26.Braughler, J. M., and Hall, E. D. 1989. Central nervous system trauma and stroke. I. Biochemical considerations for oxygen radical formation and lipid peroxidation. Free. Radical Biol. Med., 6:289–301.Google Scholar