Abstract
Aspartame and its major metabolite phenylalanine were studied for their capacity to potentiate metrazol, electroshock, and quinolinic-acid-induced seizures in rats. Pretreatment with 0.75 and 1 g/kg aspartame or 0.250 and 0.500 g/kg phenylalanine administered by gavage significantly increased the number of animals undergoing convulsions after a dose of 65.9 mg/kg of metrazol. This effect was no longer significant when 1 g/kg aspartame was given as three divided doses over two hours, after a meal or overnight with food and drinking water. However, a dose of 1 g/kg aspartame or 0.500 g/kg phenylalanine did not influence the threshold electrical current necessary to elicit convulsions in 50% of animals or the limbic seizures induced by convulsant doses of quinolic acid. After doses of 1 g/kg aspartame or 0.500 g/kg phenylalanine, striatal and hippocampal levels of 5-HT, NA, DA and their metabolites were not significantly modified. Also, in vivo release of striatal DA measured by brain microdialysis was not changed by treatment with these compounds. Under different treatment schedules, significant increases in brain phenylalanine and tyrosine were observed in rats treated acutely with doses of 250 mg/kg or more.
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© 1988 Birkhäuser Boston
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Garattini, S. et al. (1988). Studies on the Susceptibility to Convulsions in Animals Receiving Abuse Doses of Aspartame. In: Wurtman, R.J., Ritter-Walker, E. (eds) Dietary Phenylalanine and Brain Function. Birkhäuser Boston. https://doi.org/10.1007/978-1-4615-9821-3_15
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DOI: https://doi.org/10.1007/978-1-4615-9821-3_15
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