RESUMEN
The administration of L-cysteine (500 mg/kg i.p.) 30 min before and 5 h after the administration of (+)-amphetamine sulfate markedly attenuated the persistent decreases in striatal dopamine (DA), dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in rats one week after the administration of a single dose of amphetamine (9.2 mg/kg i.p.) to iprindole-treated animals and in mice one week after the last of four daily injections of amphetamine (30 mg/kg i.p.). Cysteine prevented the persistent decreases in striatal serotonin (5HT) and 5-hydroxyindoleacetic acid (5HIAA) one week after the administration of p-chloroamphetamine to rats, but failed to alter the persistent decreases in striatal DA, DOPAC and HVA in mice one week after the last of four daily doses of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, 30 mg/kg s.c.). The results suggest that the mechanisms by which amphetamine and p-chloroamphetamine, but not MPTP, produce persistent depletions of striatal monoamines involve the generation of neurotoxic electrophilic intermediates which can be inactivated by the administration of cysteine.