Orientadora: Profª Drª Marcela Bermúdez Echeverry / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Neurociência e Cognição, 2015. / Estudos tem mostrado que o fator de transcricao FosB/ delta FosB e regulado em resposta ao tratamento cronico com antipsicoticos. Porem, so a regulacao do fator FosB no estriado pode ter uma relevancia funcional nas alteracoes motoras pelos antipsicoticos tipicos e atipicos, uma vez que o gene e expressado na via direta e indireta do estriado. Assim, o objetivo do presente trabalho foi determinar se as alteracoes motoras induzidas pela administracao cronica de haloperidol, olanzapina ou clozapina regulam a expressao do FosB de maneira diferenciada no estriado motor e limbico. Metodos: Camundongos adultos machos C57Bl receberam injecao intraperitoneal agudo, subcronico ou cronico de Haloperidol, Olanzapina ou Clozapina. Tambem foram avaliados os efeitos extrapiramidais. Experimento 1: Administracao subcronica (5 dias) foi estudado com haloperidol 4 mg/Kg, olanzapina 15 mg/Kg ou Clozapina 20 mg/Kg para confirmar o efeito cataleptico. Experimento 2: As alteracoes motoras apos do tratamento cronico (77 dias) foram avaliadas com o teste de catalepsia, campo aberto, rota rod, pole test e vacuous chewing movement, com as mesmas doses do experimento 2. No ultimo experimento a expressao da proteina FosB foi avaliada. Resultados: Experimento 1: Com a administracao subcronica tipicos e atipicos induzem a catalepsia, sendo menor com os atipicos. Experimento 2: O tratamento cronico com os dois grupos de neurolepticos induzem alteracoes motoras. Foi observado aumenta da imobilizacao no teste de catalepsia e no campo aberto, sendo maior no grupo Haloperidol. Tambem foi observado alteracao no rota rod. Los grupos Haloperidol e Olanzapina tiveram aumento da expressao do FosB no estriado dorsal e ventral. Porem, o grupo Olanzapina no mostrou aumento na regiao Core do nucleo accumbens, resultado oposto observado com a Clozapina, onde mostrou aumento da expressao na regiao limbica do estriado, sem ser significativo na parte dorsal. Conclusoes: O padrao da expressao do FosB na regiao Core do nucleo accumbens, pode ser correlacionado com os sintomas parkinsonianos induzidos pelos antipsicoticos atipicos como a Clozapina. Assim, a regiao Core, poder ser inclusa na circuitaria dos nucleos basais para o estudo das alteracoes motoras induzidas pelos antipsicoticos. / Background: Studies have shown that the transcription factor FosB/ÄFosB is upregulated in response to chronic neuroleptic treatment. Moreover, regulation of only the factor FosB in striatum might have functional relevance to the motor side effects by either typical or atypical neuroleptics, once this gene is expressed in striatal direct and indirect pathways. Therefore, the goal of this study was determine whether the motor side effects after chronic administration of haloperidol, olanzapine or clozapine shown differential regulation FosB expression in motor and limbic caudate putamen. Methods: Adult male mice C57Bl received either acute, subchronic, or chronic intraperitoneally injections of haloperidol, olanzapine or clozapine, and extrapyramidal effects were evaluated.. Experiment 1: Subchronic administration (5 days) was studied with haloperidol 4 mg/Kg, Olanzapine 15 mg/Kg and clozapine 20 mg/Kg to confirm a steady cataleptic effect. Experiment 2: the motor side effects after chronic treatment (77 days) was evaluated through the catalepsy test, open field, Rota Rod, pole test and vacuous chewing movements, with same doses that experiment 2. Expression FosB protein in the last experiment was examined. Results: Experiment 1: with subchronic administration both typical and atypical neuroleptics induced cataleptic effect, even though the effect was lower with olanzapine and clozapine Experiment 2: chronic treatment showed motor side effects in both neuroleptics groups, evaluated with catalepsy test, open field, with an increased immobilization time in haloperidol group. Also, an alteration in Rota Rod test was observed with both neuroleptics groups, however, haloperidol group was unique showing increased time in pole test, with a little number of vacuous chewing movements but not significant. Haloperidol and olanzapine groups showed increased FosB protein expression in dorsal and ventral striatum. However, olanzapine group had not expression in the Core region in accumbens nucleus, opposite to clozapine group that showed an enlarged expression in this limbic/motor region, with scarcely expression in dorsal striatum. Conclusions: A unique pattern of regulation of FosB expression in core region, accumbens nucleus, may correlates with parkinsonism effect of the atypical neuroleptics, clozapine. Therefore, core region could be included in the basal ganglia circuit to study motor alterations by neuroleptics.