Avaliação da atividade de ectonucleotidases no córtex cerebral e plaquetas de ratos expostos à fumaça de cigarro

Detalhes bibliográficos
Ano de defesa: 2009
Autor(a) principal: Thomé, Gustavo Roberto
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Santa Maria
BR
Bioquímica
UFSM
Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: http://repositorio.ufsm.br/handle/1/11108
Resumo: Inflammatory and degenerative pathophysiological processes within the central nervous system (CNS) and platelets are important causes of human disease promoted by cigarette smoke. The objective of the present study was to evaluate activity of the enzymes that hydrolyze nucleotides and nucleosides in synaptosomes of cerebral cortex and platelets from rats exposed to aged and sidestream diluted smoke of commercial cigarettes. The animals were randomly divided into two groups (ten rats in each group): control (not exposed to cigarette smoke) and smoke (exposed to cigarette smoke). The smoke group was exposed via inhalation through the nose only 15 minutes per day inside a cigarette smoke exposure chamber during 3 weeks. The results demonstrated that E-NTPDase (with ATP and ADP as substrate) activity was significantly higher in the smoke group (p<0.05), while the 5'- nucleotidase with AMP as substrate demonstrated decreased activity in the smoke group (p<0.05). However, in platelets activities demonstrated that E-NPP and ENTPDase with ATP as substrate and 5´-nucleotidase with AMP as substrate were significantly higher in the smoke group (p<0.05) as compared to the control group, while E-NTPDase with ADP as substrate demonstrated decreased activity in the smoke group (p<0.05). A decrease of adenosine, a neuroprotective nucleoside, was observed in brain, which could lead to damage of the brain tissue. However, in platelets, there was an increase of adenosine, which may reflect adaptative changes. These alterations caused by cigarette smoke on ectonucleotidase activities may assist in verifying pathophysiological effects in biological systems.