RESUMO
The effects of tiazofurin (TR; 2-beta-d-ribofuranosylthiazole-4-carboxamide), a purine nucleoside analogue on basal and amphetamine (AMPH)-induced locomotor and stereotypic activity of adult Wistar rat males were studied. The animals were injected with low (3.75, 7.5, and 15 mg/kg ip) and high (62.5, 125, and 250 mg/kg ip) TR doses. Neither low nor high TR doses influenced basal locomotor and stereotypic activity in comparison with the corresponding controls treated with saline only. However, pretreatment with TR at any dose applied, except for the lowest one, significantly decreased AMPH-induced (1.5 mg/kg ip) locomotor activity, while AMPH-induced stereotypic activity was inhibited with the two highest TR doses. In addition, TR was detected in the brain by HPLC already 15 min after the injection (125 mg/kg ip) to reach a maximum 2 h after the administration and was detectable in this tissue during the next 4 h. Our results indicate that TR modifies central regulation of the motor activity, possibly by influencing dopaminergic (DA-ergic) transmission.
Assuntos
Anfetamina/farmacologia , Atividade Motora/efeitos dos fármacos , Ribavirina/análogos & derivados , Ribavirina/farmacologia , Anfetamina/antagonistas & inibidores , Animais , Relação Dose-Resposta a Droga , Masculino , Atividade Motora/fisiologia , Ratos , Ratos WistarRESUMO
The aim of the present study was to examine motor effects of amphetamine (AMPH) in rats pretreated with either dizocilpine (MK-801) or phencyclidine (PCP), and to estimate possible differences in these effects. Our results showed that AMPH increases the duration of motor effects of PCP, while it does not change motor effects of MK-801. These findings may reflect different mechanisms of action of MK-801 and PCP, as well as selective influence of AMPH on metabolism of these drugs.