Ml. Vizuete et al., 1-METHYL-4-PHENYLPYRIDINIUM HAS GREATER NEUROTOXIC EFFECT AFTER SELENIUM DEFICIENCY THAN AFTER VITAMIN-E-DEFICIENCY IN RAT STRIATUM, European journal of pharmacology. Environmental toxicology and pharmacology section, 270(2-3), 1994, pp. 183-187
The present study was designed to assess the extent of the protective
effect of antioxidative capacity of dopaminergic neurons against the p
ossible oxidative stress produced by 1-methyl-4-phenylpyridinium. We h
ave studied the direct effect of 1-methyl-4-phenylpyridinium on striat
um slices from rats fed with selenium-deficient or vitamin E-deficient
diets for 30 days. Glutathione peroxidase activity decreased signific
antly after selenium dietary restriction. Our results showed that the
effect of 1-methyl-4-phenylpyridinium on dopamine and its metabolites
3,4-dihydroxyphenylacetic acid, homovanillic acid and 3-methoxytyramin
e in animals with both restriction diets was higher than in controls.
However, this effect was significantly greater in animals with low sel
enium diets than with vitamin E-deficient diets in terms of dopamine,
3,4-dihydroxyphenylacetic acid and homovanillic acid, which were all s
ignificantly more depleted by 1-methyl-4-phenylpyridinium in selenium-
deficient rats than in vitamin E-deficient rats. Therefore, considerin
g changes in the levels of dopamine and its metabolites as an index of
1-methyl-4-phenylpyridinium toxicity, our results seem to indicate th
at the glutathione-glutathione peroxidase system has a greater protect
or effect than vitamin E.