Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-03-23T15:01:59Z
No. of bitstreams: 1
TES_HELENA_FETTER_FILIPPINI_PARCIAL.pdf: 1312432 bytes, checksum: dda78ca2fa347004234d72add7b38398 (MD5) / Made available in DSpace on 2017-03-23T15:01:59Z (GMT). No. of bitstreams: 1
TES_HELENA_FETTER_FILIPPINI_PARCIAL.pdf: 1312432 bytes, checksum: dda78ca2fa347004234d72add7b38398 (MD5)
Previous issue date: 2017-01-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The central and peripheral mechanisms involved in pulpal pain are still unclear. This study compared, initially, the chronic pulpitis model evoked by the application of complete Freund's adjuvant (CFA) into the pulps of rats, with other models of pulpitis. For this purpose, the pulps of the left upper first molars of Wistar rats were accessed. There were four experimental groups according to the surgical procedure: open, closed, CFA and na?ve. Behavioral changes, as well as, body weight gain and food and water consumption, were evaluated at different experimental times (1, 2, 3 and 8 days). After euthanasia, blood, brain and trigeminal ganglion (TG) samples were collected for further analysis. All experimental groups with pulp acess had a decrease in body weight gain (for up to 3 days). A reduction in food consumption was observed in all the groups with pulp exposure, on the first day. The CFA group showed a significant reduction of locomotor activity (at 1 and 3 days), which was associated with increased satellite glial cells activation in the ipsilateral TG. Activation of astrocytes in the amygdala was not affected in the studied groups. The second part of this study investigated the relevance of Toll-like receptor 4 (TLR4) activation in the acute pulpitis caused by the application of the transient receptor potential ankyrin-1 (TRPA1) mustard oil (MO), into the rat pulps. Preliminary studies were performed to compare the sensorimotor activity of the masticatory muscles with the application of lipopolysaccharide (LPS) or MO in the dental pulp. The model using MO application into the pulp of rats was selected, because of the marked increase of the electromyographic activities evoked by this agent, when compared to LPS. The animals received a intrathecal (i.t.) pre-treatment with the TLR4 LPS-RS antagonist (25 ?g / 10 ?l) or saline solution (10 ?l) (vehicle group), 10 min before pulp application of MO. For this purpose, a stereotaxic surgery was performed to access the trigeminal subnucleus caudalis. Changes in electromyography activity (EMG) of masticatory muscles were recorded for 15 min after the MO application into the pulp. The trigeminal caudalis subnucleus was removed after euthanasia, for evaluation of TLR4 expression by western blotting analysis. Changes in EMG activity in anterior digastric muscles were significantly reduced by the intrathecal administration of LPS-RS in the trigeminal subnucleus caudalis (p ?0.05). The data obtained suggest the participation of satellite glial cells in the chronic pulpitis model induced by CFA, as well as, TLR4 receptors in the acute pulpitis model caused by MO application into the rat pulps. Altogether, the present results shed new light on the mechanisms underlying acute and chronic tooth pulp inflammatory pain. / Os mecanismos centrais e perif?ricos envolvidos na dor pulpar ainda n?o est?o totalmente claros. O presente estudo comparou, inicialmente, o modelo de inflama??o pulpar cr?nica induzido pela aplica??o de adjuvante completo de Freund (CFA), em polpas de ratos, com outros modelos de pulpite. Para tanto, as polpas dos primeiros molares superiores esquerdos de ratos Wistar foram acessadas. Foram criados 4 grupos experimentais conforme a abordagem pulpar: aberto, fechado, CFA e na?ve. As altera??es comportamentais, bem como, o ganho de peso corporal e o consumo de ?gua e ra??o, foram avaliados em diferentes tempos experimentais (1, 2, 3 e 8 dias). Ap?s a eutan?sia, amostras de sangue, c?rebro e g?nglio trigeminal (GT) foram coletadas para an?lises posteriores. Todos os grupos experimentais com exposi??o da polpa apresentaram diminui??o do ganho de peso corporal (at? o 3 ? dia). A redu??o do consumo de ra??o foi observada em todos os grupos no primeiro dia. O grupo CFA mostrou redu??o significativa na atividade locomotora (em 1 e 3 dias), que foi associada ao aumento da ativa??o das c?lulas sat?lites da glia no GT ipsilateral. A ativa??o de astr?citos na am?gdala n?o foi afetada nos grupos estudados. A segunda parte deste estudo investigou a participa??o do receptor Toll-like 4 (TLR4), na media??o da pulpite aguda causada pela aplica??o de ?leo de mostarda (OM), um agonista de receptores de potencial transit?rio anquirina-1 (TRPA1), em polpas de ratos. Estudos preliminares foram realizados comparando a atividade sensoriomotora dos m?sculos mastigat?rios diante da aplica??o de lipopolissacar?deo (LPS) ou OM na polpa dent?ria. O modelo utilizando OM na polpa de ratos foi escolhido, devido ao aumento marcante das atividades eletromiogr?ficas (EMG), quando comparado ao LPS. Os animais foram pr?-tratados por via intratecal (i.t.) com o antagonista seletivo dos receptores TLR4, o LPS-RS (25 ?g/10 ?l, 10 min antes da aplica??o pulpar de OM. O grupo controle recebeu solu??o salina (10 ?l) (grupo ve?culo), pela mesma via, no mesmo tempo de administra??o. Para tal, foi realizada uma cirurgia esterot?xica para permitir o acesso ao subn?cleo caudal trigeminal. As altera??es das atividades de EMG dos m?sculos mastigat?rios foram registradas durante 15 min ap?s a aplica??o de OM na polpa. O subn?cleo caudal trigeminal foi removido ap?s a eutan?sia, para avalia??o da express?o de TLR4, atrav?s da an?lise de western-blotting. As altera??es da atividade de EMG nos m?sculos dig?stricos anteriores foram significativamente reduzidas pela administra??o intratecal de LPS-RS no subn?cleo caudal do trig?meo (p?0,05), indicando um papel relevante para esses receptores nos mecanismos de sensibiliza??o central, ap?s a aplica??o de OM. O conjunto de dados obtidos sugerem a participa??o das c?lulas sat?lites da glia no modelo de pulpite cr?nica induzida por CFA, bem como, dos receptores TLR4 no modelo de pulpite aguda provocada pela aplica??o de OM em polpas de ratos. Essas evid?ncias contribuem para o melhor entendimento dos mecanismos relacionados com a transmiss?o da dor pulpar aguda e cr?nica.
| Identifer | oai:union.ndltd.org:IBICT/oai:tede2.pucrs.br:tede/7184 |
| Date | 13 January 2017 |
| Creators | Filippini, Helena Fetter |
| Contributors | Campos, Maria Martha |
| Publisher | Pontif?cia Universidade Cat?lica do Rio Grande do Sul, Programa de P?s-Gradua??o em Odontologia, PUCRS, Brasil, Faculdade de Odontologia |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da PUC_RS, instname:Pontifícia Universidade Católica do Rio Grande do Sul, instacron:PUC_RS |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | -8096554818733665164, 600, 600, 600, 600, 600, 4673435736271820140, -2070498469879244349, 2075167498588264571, -2555911436985713659 |
Page generated in 0.0027 seconds