Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-13T10:59:16Z No. of bitstreams: 1 AnnaraYveMouraSoares_DISSERT.pdf: 884763 bytes, checksum: df8a008c0603a2358c6331d336c3bd21 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-20T14:53:34Z (GMT) No. of bitstreams: 1 AnnaraYveMouraSoares_DISSERT.pdf: 884763 bytes, checksum: df8a008c0603a2358c6331d336c3bd21 (MD5) / Made available in DSpace on 2017-01-20T14:53:34Z (GMT). No. of bitstreams: 1 AnnaraYveMouraSoares_DISSERT.pdf: 884763 bytes, checksum: df8a008c0603a2358c6331d336c3bd21 (MD5) Previous issue date: 2016-04-05 / Esse estudo objetiva avaliar se a express?o da enzima de reparo de DNA Neil3 ? importante para o desenvolvimento funcional dos neur?nios. Estudos previos tem demonstrado que Neil3 interfere tanto na neurog?nese adulta como na fazer embrionaria. Eu utilizei whole cell patch clamp para estudar propriedades sinapticas e de membrana das c?lulas granulares do giro denteado. O giro denteado ? uma das regi?es com maior express?o de Neil3 no c?rebro e estudos previos tem demonstrado que a neurog?nese reativa em camundongos adultos ? afetada pela ausencia da enzima de reparo Neil3. Eu encontrei que a maioria das propriedades de membrana nas c?lulas granulares de camundongos knockout para Neil3 s?o normais com exce??o ? resposta de membrana ?s correntes de hiperpolariza??o e p?s-hiperpolariza??o. Diferentemente de neur?nios imaturos, as c?lulas granulares do giro denteado de camundongos com aus?ncia de Neil3, na qual as correntes de hiperpolariza??o ativadas s?o geralmente as ultimas a aparecerem durante o desenvolvimento. Al?m disso, correntes sinapticas excitatorias foram similar em amplitude mas apresentaram um decaimento ligeiramente mais rapido em c?lulas de camundongos knockout de Neil3. Esses resultados podem indicar um balan?o diferente entre os receptores AMPA e NMDA em camundongos knockout. Analises morfologicas de neur?nios preenchidos com biotina e reconstru??o post hoc n?o apresentaram grandes diferen?as na morfologia dendritica entre animais controle e knockout. Esse estudo mostra que, em rela??o diferen?as entre animais controle, neur?nios do giro denteado de animais knockout de Neil3 n?o podem ser classificados como imaturos. Eu encontrei diferen?as pontuais na corrente de hiperpolariza??o e pequenas diferen?as em propriedades sinapticas. Ainda devem ser avaliadas se essas diferen?as podem ser respons?veis por altera??es comportamentais encontradas em camundongos Neil3-knockout. Al?m disso, estudos futuros utilizando marcadores de neur?nios rec?m-nascidos s?o necess?rios para analisar o efeito da elimina??o da enzima Neil3 no desenvolvimento de neur?nios. / This study aims to assess whether the expression of the DNA repair enzyme Neil3 is important for the functional development of neurons. Previous studies have demonstrated that Neil3 interferes with both adult and embryonic neurogenesis. I have used whole cell patch clamp to study membrane and synaptic properties of granule cells of the dentate gyrus. The dentate gyrus is one of the regions with the highest expression of Neil3 in the brain, and previous studies have shown that reactive neurogenesis in adult mice is affected by Neil3 deletion. I found that most membrane properties of granule cells in Neil3-knockout mice are normal except from the membrane response to hyperpolarization currents and afterhyperpolarization currents. Different from immature neurons, granule cells of the dentate gyrus from Neil3-knockout mice, in which hyperpolarizing activated currents, are generally the last to appear during development. In addition, excitatory synaptic currents were similar in amplitude but showed a slightly faster decay in cells from Neil3-knockout mice. These results could indicate a different balance between AMPA and NMDA receptors in Neil3-knockout mice cells. Morphological analysis of neurons filled with biocytin and reconstructed post hoc showed no gross difference in dendritic morphology between dentate gyrus neurons of control and Neil3-knockout mice. This study shows that, while different from those of control littermates, dentate gyrus neurons of Neil3-knockout mice cannot be classified as ?immature?. I found specific differences in hyperpolarizing activated currents and small differences in synaptic properties. Whether these differences may account for behavioral changes found in Neil3-knockout mice is yet to be assessed. In addition, future studies using markers of newly born neurons are necessary for analyzing the effect of Neil3 deletion in developing neurons.