Effects of iron-induced lipid peroxidation and of acidosis on choline uptake by synaptosomes
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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