Efeitos da exposição crônica intermitente ao organofosforado clorpirifós sobre as funções comportamentais e cardiovasculares em ratos

• Ano de defesa: 2023
• Autor(a) principal: Rosa, Yuri Fernandes Pereira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Ciências Farmacêuticas; Centro de Ciências da Saúde; UFES; Programa de Pós-Graduação em Ciências Farmacêuticas
• Palavras-chave em Português: Organofosforado; Clorpirifós; Acetilcolinesterase; Labirinto de cruz elevado; Ansiedade; Medo condicionado ao contexto; subject.br-rjbn; Farmácia
• Link de acesso: http://repositorio.ufes.br/handle/10/16837

Chlorpyrifos (CPF) is a compound belonging to the organophosphates (OP's) group that is widely used in agricultural production and exerts a toxic activity by inhibiting acetylcholinesterase (AChE), resulting in an accumulation of acetylcholine (Ach) and hyperstimulation of central and peripherall cholinergic receptors. Repeated and intermitente exposure of rats to CPF seems to impair the cardiovascular reflexes. There is also preclinical and clinical evidence that CPF exposure induces some cognitive impairments, anxiety, irritability, nervousness, depression and aggression. However, there are no preclinical studies that have analyzed if repeated and intermittent exposure to CPF would impair the behavioral and cardiovascular responses associated with aversive stimuli. In the present study, adult Wistar rats were submitted to a protocol of repeated intermittent exposure to CPF (4 mg/kg or 7 mg/kg) for 4 weeks, on alternate days. CPF effects on locomotor activity and anxiety were evaluated in the open field (OF) and elevated plus maze (EPM) test. CPF effects on anhedonia were evaluated in the sucrose preference test. To assess cardiovascular changes and aversive memory, the contextual fear conditioning (CFC) associated with hemodynamic recordings was used. CPF treatment does not changed sucrose preference. In the EPM test, there wasn’t change in the percentage of entries into the open and closed arms, but there was a reduction in the time spent by animals treated with CPF in the open arms. In OF test, animals treated with CPF 7 group showed impaired locomotor activity. In the CFC, the animals were conditioned and were able to extinghish freezing responseDuring the extinction session, the animals treated with CPF 7 mg/kg showed a higher heart rate in response to the aversive environment. There was no impairment in the consolidation of fear extinction. Our results suggest that repeated and intermittent exposure with CPF results in behavioral and cardiovascular impairments.