Antioxidant Effects of Serotonin and L-DOPA on Oxidative Damages of Brain Synaptosomes
Antioxidant Effects of Serotonin and L-DOPA on Oxidative Damages of Brain Synaptosomes
- Sang Soo Ham Dong Hyun Kim Suk Ha Lee Yun Sang Kim Chung Soo Lee
- 대한생리학회-대한약리학회
- The Korean Journal of Physiology & Pharmacology
- 제3권 제2호
- 등재여부 : KCI등재
- 1999.01
- 147 - 155 (9 pages)
<P> Antioxidant effects of serotonin and L-DOPA on neuronal tissues were examined by studying the oxidative damages of brain synaptosomal components. The study further explored the mechanism by which they exert protective actions. Serotonin and L-DOPA (1 μM to 1 mM) significantly inhibited lipid peroxidation of brain tissues by either Fe<SUP>2⁢</SUP> and ascorbate or t-butyl hydroperoxide in a dose dependent fashion. Protective effect of serotonin on the peroxidative actions of both systems was greater than that of L-DOPA. Protein oxidation of synaptosomes caused by Fe<SUP>2⁢</SUP> and ascorbate was attenuated by serotonin and L-DOPA. Protein oxidation more sensitively responded to L-DOPA rather than serotonin. Serotonin and L-DOPA (100 μM) decreased effectively the oxidation of synaptosomal sulfhydryl groups caused by Fe<SUP>2⁢</SUP> and ascorbate. The production of hydroxyl radical caused by either Fe<SUP>3⁢</SUP>, EDTA, H<SUB>2</SUB>O<SUB>2</SUB> and ascorbate or xanthine and xanthine oxidase was significantly decreased by serotonin and L-DOPA (1 mM). Equal concentrations of serotonin and L-DOPA restored synaptosomal Ca<SUP>2⁢</SUP> uptake decreased by Fe<SUP>2⁢</SUP> and ascorbate, which is responsible for SOD and catalase. Protective effects of serotonin and L-DOPA on brain synaptosomes may be attributed to their removing action on reactive oxidants, hydroxyl radicals and probably iron-oxygen complex, without chelating action on iron.