Effect of d-amphetamine and sydnocarb on the extracellular level of dopamine, 3,4-dihydroxyphenylacetic acid, and hydroxyl radicals generation in rat striatum.

d-AMPH and its congeners are able to produce several neurotoxic effects, including behavioral evidences of dopaminergic dysfunction, enhanced generation of reactive oxygen species, and depletion of endogenous DA. As has been shown, Sydnocarb produces a slow and gradual increase of the parameters of dopaminergic dysfunction. Present investigations report that Sydnocarb, the original Russian psychostimulant, at a dose of 23.8 mg/kg (equimolar to 5 mg/kg d-AMPH) elicited a moderate increase in the extracellular level of DA. We found that Sydnocarb increased OH generation in less degree than that by d-AMPH. Sydnocarb was also able to elicit stereotyped behavior, but to a less extent than d-AMPH. Differences between the mode of action of this drug were previously observed. In our study, the DOPAC extracellular level was significantly decreased after the fourth injection of Sydnocarb, unlike with d-AMPH treatment. Taken together, this finding probably reflects less neurotoxic potential of the novel, original psychostimulant Sydnocarb with good clinical efficaciousness in comparison to the amphetamine.