No description available.

INTRODUÇÃO: A falência intestinal constitui uma grave entidade patológica. Uma das opções para estes casos complexos, como a síndrome de Gardner e a dismotilidade intestinal, é o transplante multivisceral modificado (TxMvm). A literatura científica ainda carece de um modelo experimental animal para o TxMvm, além do estudo de seus efeitos hemodinâmico e metabólico. A análise foi feita em dois dos três tipos de TxMvm: na evisceração maior e no modelo de preservação esplênica. Essas técnicas levam a grandes modificações anatômicas e hemodinâmicas que, somadas ao processo de evisceração esplâncnica, contribuem para redução da pré-carga e consequentemente do débito cardíaco (DC). O objetivo geral é descrever um modelo de evisceração das duas técnicas utilizadas no TxMvm em porco. O específico é descrever e comparar as alterações hemodinâmicas e metabólicas sistêmicas e regionais da evisceração abdominal nestas duas técnicas. MÉTODO: Foram utilizados 14 suínos (Landrace), pesando de 28 a 30 kg, que foram anestesiados, submetidos à ventilação mecânica e monitorizados hemodinamicamente. Os animais foram divididos aleatoriamente em dois grupos: grupo 1 (n=8), submetido à evisceração completa dos órgãos intra-abdominais, com exceção do fígado, e grupo 2 (n=6), submetidos à mesma evisceração com preservação esplênica. As variáveis hemodinâmicas foram obtidas através de cateter na aorta torácica e um cateter de Swan-Ganz. A avaliação da perfusão esplâncnica foi realizada com cateteres posicionados nas veias porta e hepática, e através de fluxômetro ultra-sônico. A oferta, o consumo e as taxas de extração sistêmica, hepática e esplâncnica de oxigênio foram calculados por meio de fórmulas padrão. Amostras de histologia hepática para avaliação mitocondrial, de apoptose e de imunohistoquímica foram colhidas durante todo o protocolo experimental, assim como sangue para análises gasométrica e bioquímica. RESULTADOS: Embora não tenha havido diferença significativa entre os grupos na análise transversal, na longitudinal a DO2 apresentou diferença significativa no grupo 1 a partir do T120, e no grupo 2, a partir do T60. Houve queda sustentada do consumo de oxigênio (VO2) em ambos os grupos. A extração de oxigênio hepático (TEO2 hep) também decaiu, mas com recuperação em T180 no grupo 2, enquanto no grupo 1, o VO2 hepático apresenta queda significativa. A variável S4 apresenta alteração significativa ao fim do estudo. Não houve diferença quanto às análises histológicas e imunohistoquímica. CONCLUSÃO: O modelo descrito nesta tese foi efetivo em observar as alterações hemodinâmicas, metabólicas e histopatológicas da evisceração em ambas as técnicas do TxMvm. A evisceracão abdominal foi associada a alterações hemodinâmicas sistêmicas e regionais significativas. Apesar da redução do DC, os marcadores metabólicos e bioquímicos de lesão hepática permaneceram inalterados ao final do estudo / INTRODUCTION: Intestinal failure is a very severe pathology consequence of some diseases such as Gardner\'s syndrome and intestinal motility disorder. There are some treatment options, one of them is the modified multivisceral transplantation (TxMvm). There is no description in scientific literature about an experimental animal model for TxMvm and the study of its hemodynamic and metabolic effects. This assignment was done in two of the three types of TxMvm: in major evisceration and in splenic preservation model. These techniques lead to major anatomical and hemodynamic modifications that, together with the splanchnic evisceration process, contribute to reduction in preload and consequently cardiac output (CO). The general objective is to describe a model of evisceration of two techniques used in TxMvm in pork. The specific objective is to describe and compare the hemodynamic and systemic and regional metabolic changes of abdominal evisceration in these two techniques. METHOD: Fourteen pigs (Landrace) weighing 28 to 30 kg were used, which were anesthetized, submitted to mechanical ventilation and monitored hemodynamically. The animals were randomly assigned to two groups: group 1 (n = 8), submitted to complete evisceration of intra-abdominal organs, with the exception of liver, and group 2 (n = 6), submitted to the same evisceration with splenic preservation. Systemic and regional hemodynamics were evaluated using Swan-Ganz, ultrasonic flowprobes, and arterial catheters. Serial blood samples were collected for blood gas, electrolyte and serum chemistry analysis. Systemic, hepatic and splanchnic O2-derived variables were also calculated. Liver histological samples for mitochondrial evaluation, apoptosis and immunohistochemistry were collected throughout the experimental protocol. RESULTS: Although there was no significant difference between the groups in the transversal analysis, in the longitudinal one, DO2 (oxygen delivery) presented a significant difference in group 1 from T120, and in group 2, from T60. There was a sustained decrease in oxygen consumption (VO2) in both groups. Hepatic oxygen extraction (TEO2 hep) also declined, but recovered in T180 in group 2, whereas in group 1, hepatic VO2 presented a significant decrease. Variable S4 presented a significant change at the end of the study. There was no difference regarding histological and immunohistochemical analyzes. CONCLUSION: The model described in this thesis was effective in observing the hemodynamic, metabolic and histopathological changes of evisceration in both TxMvm techniques. Abdominal evisceration was associated with significant systemic and regional hemodynamic changes. Despite the reduction in CO, the metabolic and biochemical markers of liver injury remained unchanged at the end of the study

Introdução: As citocinas de perfil Th17 parecem exercer um papel importante na fisiopatogenia da inflamação pulmonar alérgica crônica, embora sua exata influência seja incerta. Estudos demonstram uma influência destas citocinas em modular a resposta inflamatória e infecciosa. É importante enfatizar que a infecção é um dos responsáveis por perpetuar a resposta inflamatória crônica na asma, particularmente durante as exacerbações. Muitos dos efeitos desta via ainda não foram investigados em modelos de inflamação alérgica pulmonar crônica (asma) exarcebada pelo lipopolissacarídeos (LPS). Objetivos: Avaliar os efeitos do tratamento com anti-IL-17 em um modelo de inflamação pulmonar alérgica crônica exarcebada pelo LPS. Métodos: Camundongos BALB/c foram submetidos ao protocolo de indução alérgica crônica das vias aéreas com ovoalbumina ou salina e com posterior desafios inalatórios por 28 dias. Nos 1° e 14° dias um grupo (grupo OVA) recebeu ovoalbumina 50 mg em hidróxido de alumínio 6mg em um volume total de 0,2 ml por via intraperitoneal. Do 22° ao 28° dia, os animais receberam em dias alternados, inalação de aerossol de OVA diluída em NaCl 0,9% (soro fisiológico) na concentração de 10 mg/ml (1%) por 30 minutos. Ao mesmo tempo, o grupo controle (grupo SAL) recebeu solução salina (NaCl 0,9%) e hidróxido de alumínio (6 mg) por via intraperitoneal e nos dias dos desafios inalatórios foram expostos ao aerossol de solução salina 0,9% também por 30 minutos. Uma hora antes da inalação de ovoalbumina ou de salina, o anticorpo neutralizador anti-IL17 foi administrado por via intraperitoneal (ip) (grupos OVA-antiIL17 e SAL-antiIL17). Vinte e quatro horas antes do final do protocolo experimental (28° dia) um grupo de animais (grupo OVA-LPS) recebeu instilação traqueal de LPS (20 ?l de PBS + 0,1 mg / ml de Escherichia coli 0127: B8). O grupo sensibilizado que recebeu LPS e anti-IL17uma hora antes da exposição ao LPS foi chamado de OVA-LPS-antiIL17. No 29° dia do protocolo, os animais foram eutanasiados e inicialmente foram avaliadas as respostas máximas à metacolina da resistência e elastância do sistema respiratório. Os pulmões foram retirados e realizados as análises histológicas e morfométricas para avaliar a expressão celular de CD4+, CD8+, células dendríticas e células reguladoras T FOXP3; RT-PCR para arginase 1, transportador vesicular de acetilcolina (VAChT) e IL-17; ativação do fator de transcrição nuclear ?B (NF-?B); o número de células positivas para ROCK 1 e ROCK 2; resposta inflamatória de perfis Th1 (IL-2, IL-6, e TNF-alfa), Th2 (IL-4, IL-5, IL-10 e IL-13), Th-17 (IL-17), quimiocinas CCL17/TARC e CCL11/Eotaxina; resposta de remodelamento da matriz extracelular (conteúdo de fibras colágenas tipos I e III, decorina, lumican, biglicano, fibronectina, actina, TGFbeta1, o número de células positivas para MMP-9, MMP-12 e TIMP-1), e a resposta de estresse oxidativo (o número de células positivas para iNOS e conteúdo de isoprostano PGF2alfa e Arginase 1). Além disso, avaliamos por reação em cadeia da polimerase em tempo real (Real-time PCR) a expressão gênica de IL-17 e mRNA para VAChT As análises estatísticas foram realizada por meio do programa SigmaStat (Jandel Scientific, San Rafael, CA), onde um p < 0,05 será considerado estatisticamente significativo. Resultados: O grupo OVA-LPS-antíIL17 apresentou uma diminuição na resposta máxima pós metacolina de elastância e resistência do sistema respiratório, NO exalado, o número de células positivas para CD4+ e CD8+, células dendríticas, células T reguladoras FOXP3, mRNA para VAChT, NF-?B, ROCK1 e 2, quimiocinas CCL17 / TARC, e CCL11 / eotaxina, IL2 IL4, IL5, IL6, IL10, IL13 e IL17 nas paredes das vias aéreas comparado aos grupos OVA e OVA-LPS (p < 0,05). Alem disso, o tratamento com anti-IL17 reduziu o remodelamento brônquico (conteúdo de fibras colágenas I e III, decorina, lumican, biglican e fibronectina nas paredes das vias aéreas) assim como o número de células positivas para TGFbeta1, MMP-9, MMP12 e TIMP-1 ao redor das vias aéreas em comparação ao grupo SAL (p < 0.05). Houve também a atenuação de todos os parâmetros exceto no grupo OVA-antiIL17 em comparação ao grupo OVA (p < 0.05). Quanto ao estresse oxidativo o tratamento com o anti-IL17 também foi efetivo. Observamos redução de expressão celular de iNOS, conteúdo de PGF2alfa e expressão gênica de arginase1 em comparação com os grupos OVA e OVA-LPS (p < 0,05). Ainda, observamos uma atenuação do antí-IL17 na expressão gênica de IL17 e VAChT. Conclusões: A inibição da IL17 contribuiu para o controle da hiperresponsividade brônquica, da inflamação Th1/Th2/Th17, da expressão de quimiocinas, do remodelamento da matriz extracelular e da resposta da via NO-arginase, do sistema colinérgico sinalizado pela avaliação do VAChT e de estresse oxidativo no modelo de asma experimental. No modelo de asma experimental exarcebado pelo LPS houve potencialização das respostas de hiperresponsividade das vias aéreas distais, assim como da maioria dos marcadores de resposta inflamatória, de remodelamento da matriz extracelular e da ativação das vias via NO-arginase e do estresse oxidativo. O tratamento com anti-IL17 nesses animais foi capaz de controlar a maior parte das alterações citadas, exceto o conteúdo de actina. Dentre os mecanismos envolvidos no controle pelo tratamento com anti-IL17 das alterações estudadas no modelo de asma experimental exarcebado pelo LPS observamos a importância da expressão do fator de transcrição NFkb e de Rho quinase 1, e expressão gênica mRNA para VAChT. Embora outros mecanismos possam estar envolvidos e doses repetidas de anti-IL17 nos animais com asma exarcebado pelo LPS também necessitem ser testadas, o tratamento com anti-IL17 se mostrou uma ferramenta farmacológica importante para o tratamento das alterações, que à semelhança do observado nestes modelos experimentais, também se observam em pacientes com asma grave mesmo associada a quadros infecciosos agudos / Introduction: Th17 cytokines appear to play an important role in the pathophysiology of chronic allergic pulmonary inflammation, although their exact role is uncertain. Studies have demonstrated an influence of these cytokines in modulating the inflammatory and infectious response. It is important to emphasize that infection is one of the factors responsible for perpetuating the chronic inflammatory response in asthma, particularly during exacerbations. Many of the effects of this pathway have not yet been investigated in models of chronic allergic lung inflammation (asthma) exacerbated by lipopolysaccharide (LPS). Objectives: To evaluate the effects of anti-IL17 treatment on a model of chronic allergic pulmonary inflammation exacerbated by LPS. Methods: BALB/c mice were submitted to protocol of chronic allergic induction of the airways with ovalbumin or saline and with subsequent inhaled challenges for 28 days. On days 1 and 14 a group (OVA group) received ovalbumin 50 mg in 6 mg aluminum hydroxide in a total volume of 0.2 ml intraperitoneally. From the 22 to the 28 day, the animals received, on alternate days, aerosol inhalation of OVA diluted in NaCl 0.9% (saline solution) at a concentration of 10 mg/ml (1%) for 30 minutes. At the same time, the control group (SAL group) received saline solution (NaCl 0.9%) and aluminum hydroxide (6 mg) intraperitoneally and on the days of the inhalation challenges were exposed to aerosol 0.9% saline solution for 30 minutes. One hour prior to inhalation of ovalbumin or saline, the anti-IL17 neutralizing antibody was administered i.p. (OVA-anti-IL-17 and SAL-anti-IL17 groups). Twenty-four hours before the end of the experimental protocol (28th day) one group of animals (OVA-LPS group) received LPS tracheal instillation (20 ul PBS + 0.1 mg/ml Escherichia coli 0127: B8). The sensitized group that received LPS and anti-IL17 an hour before exposure to LPS was called OVA-LPS-anti-IL-17. On the 29th day of the protocol, the animals were euthanized and initially the maximum methacholine responses of resistance and elastance of the respiratory system were evaluated. The lungs were removed and the histological and morphometric analysis were performed to evaluate the cell expression of CD4+, CD8+, dendritic cells and T regulatory cells FOXP3; RT-PCR for arginase 1, vesicular acetylcholine transporter (VAChT) and IL-17; activation of nuclear transcription factor KappaB (NFkb); the number of positive cells for ROCK 1 and ROCK 2; Th1 (IL-2, IL-6, and TNF-alpha), Th2 (IL-4, IL-5, IL-10 and IL-13), Th-17 (IL-17), CCL17 chemokines/TARC and CCL11 / Eotaxin; (content of collagen fibers types I and III, decorin, lumican, biglican, fibronectin, actin, TGFbeta1, number of cells positive for MMP-9, MMP-12 and TIMP-1), and the response of oxidative stress (the number of positive cells for iNOS and isoprostane content PGF2alpha and Arginase 1). In addition, we evaluated the gene expression of IL-17 and mRNA for VAChT by real-time PCR. Statistical analysys were performed using the SigmaStat program (Jandel Scientific, San Rafael, CA), where a p < 0.05 were considered statistically significant. Results: The OVA-LPS-anti-IL-17 group showed a decrease in post-methacholine maximal response of elastance and respiratory system resistance, exhaled NO, number of CD4 + and CD8 + positive cells, dendritic cells, FOXP3 regulatory T cells, mRNA for VAChT, (p < 0.05), and in the presence of a significant increase in the expression of IL-1, IL-6, IL-10, IL-13 and IL17 in the airway walls compared to OVA and OVA-LPS (p < 0,05). In addition, anti-IL17 treatment reduced bronchial remodeling (content of collagen fibers I and III, decorin, lumican, biglican and fibronectin in the airway walls) as well as the number of TGFbeta1, MMP-9, MMP-12 and TIMP-1 around the airways compared to the SAL group (p < 0.05). There was also attenuation of all parameters except in the OVA-antiIL17 group compared to the OVA group (p < 0.05). As for oxidative stress, treatment with anti-IL17 was also effective. We observed reduction of iNOS cell expression, PGF2alpha content and arginase1 gene expression in comparison to OVA and OVA-LPS groups (p < 0.05). Furthermore, we observed an attenuation of the anti-IL17 in the IL17 and VAChT gene expression. Conclusions: Inhibition of IL-17 contributed to the control of bronchial hyperresponsiveness, Th1/Th2/Th17 inflammation, chemokine expression, extracellular matrix remodeling and NO-arginase pathway response, cholinergic system signaled by VAChT and of oxidative stress in the experimental asthma model. In the model of experimental asthma exacerbated by LPS there was a potentation of hyperresponsiveness responses of the distal airways, as well as of the majority of inflammatory response markers, extracellular matrix remodeling and activation of the pathways via NO-arginase and oxidative stress. Treatment with anti-IL-17 in these animals was able to control most of the above-mentioned changes, except the actin content. Among the mechanisms involved in the control by anti-IL17 treatment of the alterations studied in the model of experimental asthma exacerbated by LPS, we observed the importance of the expression of the transcription factor NF-Kappa B and Rho kinase 1, and gene expression mRNA for VAChT. Although other mechanisms may be involved and repeated doses of anti-IL17 in animals with LPS-exacerbated asthma also need to be tested, treatment with anti-IL17 has proved to be an important pharmacological tool for the treatment of the changes, which similar to those observed in these experimental models, are also seen in patients with severe asthma associated with acute infectious conditions

A esclerodermia sistêmica (ES) é caracterizada por fibrose da pele e órgãos internos, ativação imunológica e vasculopatia. Os modelos animais de ES sofrem com a falta de uma prova definitiva para o envolvimento vascular observado na doença humana. Um novo modelo induzido por colágeno do tipo V (COLV) reproduz muitas características da ES como fibrose e fenômenos imunológicos. No entanto, o estudo da vasculopatia ainda não foi abordado. O objetivo desse estudo foi investigar as alterações estruturais e funcionais das células endoteliais das artérias pulmonares do modelo de ES induzido pelo COLV, assim como determinar a doença pulmonar com ênfase especial no depósito de colágeno e síntese de RNAm de colágenos. Coelhos fêmeas Nova Zelândia (n = 8) foram imunizados com COLV humano emulsificado em adjuvante de Freund ou apenas com adjuvante de Freund (controle; n = 8). Após 7, 75 e 210 dias, os animais foram sacrificados e os pulmões foram analisados por microscopia eletrônica, hematoxilina e eosina, e marcações especiais incluindo imunomarcação para neovascularização (CD31), apoptose de células endoteliais (induzida pela caspase-3) e atividade endotelial (endotelina-1 e VEGF). A resposta vascular a acetilcolina (Ach) foi estudada em anéis de artéria pulmonar isolada. Para determinar o conteúdo de colágeno, expressão RNAm dos colágenos I, III e V e quantidade de colágeno (hidroxiprolina aminoácido específico), os pulmões foram submetidos a imunofluorescência, PCR em tempo real e análise bioquímica. Foi observado que os coelhos imunizados com COLV apresentaram um aumento progressivo de apoptose e atividade das células endoteliais a partir de 7 dias quando comparados aos coelhos controle (p 0,01). Em contrapartida, apenas aos 210 dias os coelhos imunizados com COLV apresentaram aumento significativo na neovascularização quando comparados com o grupo controle (p < 0,001). Coincidente com esses achados, a microscopia eletrônica mostrou alterações das células endoteliais caracterizada por apoptose, alterações degenerativas das organelas e tumefação citoplasmática. As células endoteliais pareciam estar destacadas da membrana basal. Os coelhos imunizados com COLV de 210 dias necessitaram de uma dose maior de Ach do que os controles para alcançar o relaxamento máximo de 50% (EC50) dos anéis de artéria pulmonar (p = 0,02). Por fim, foi observado que os coelhos de 210 dias imunizados com COLV apresentaram uma intensa expressão de COLV no interstício broncovascular, acompanhado de um aumento na expressão do RNAm (p < 0,001) quando comparado ao grupo controle. Os coelhos imunizados com COLV apresentaram uma maior quantidade de conteúdo de colágeno, quando comparados com os controles, nos diferentes tempos estudados (p < 0,01). Este estudo fornece evidência para a disfunção pulmonar do endotélio vascular em coelhos com ES induzida pelo COLV. As alterações observadas, nesse estudo, reforçam o papel do endotélio como evento patogênico primário na ES. Desta forma, o modelo ES induzido pelo COLV pode fornecer informações importantes sobre a patogênese da doença humana / The hallmarks of systemic sclerosis (SSc) are fibrosis of skin and internal organs, immune activity and vasculopathy. Animal models of SSc suffer from lack of a definitive evidence for vascular involvement observed in human disease. A novel model induced by collagen type V (COLV) reproduces many features of SSc, however vascular study has not been addressed. The aim of the present study was therefore evaluate pulmonary arteries for structural and functional alterations in endothelial cells in the COLV-induced SSc model, as well as determine the lung disease with special emphasis on collagen deposition and mRNA collagen synthesis. Female New Zealand rabbits (n = 8) were immunized with human COLV/Freund´s adjuvant or Freund´s adjuvant alone (control; n = 8). After 7, 75 and 210 days, the animals were sacrificed and the lungs were examined by electron microscopy, hematoxylin&eosin and special stains including immunostaining for neovascularization (CD31), endothelial cells apoptosis (caspase-3 induced) and endothelial activity (endothelin-1 and VEGF). Vascular response to acetylcholine (Ach) on isolated pulmonary artery rings was evaluated. To determine collagen content, mRNA expressions of COL I, III and V, and the quantity of collagen-specific amino acid hydroxyproline, the lungs were submitted to immunofluorescence, real-time qPCR and biochemical examination. The COLV rabbits demonstrated an endothelial cells apoptosis and activity compared to control rabbits starting at day-7 (p 0.01). A significant increase in neovascularization was observed only in the COLV-rabbits at day-210 (p < 0,001). Coincident with these findings, the electron microscopy revealed extensive endothelial cells abnormalities characterized by apoptosis, degenerative organelle changes and cytoplasmic tumefaction. Endothelial cells appeared to be detached from the basement membrane. Ach dose required to achieve 50% maximum relaxation (EC50) of pulmonary artery rings was increased in COLV rabbits at day-210 (p = 0.02). The content of hydroxyproline was increased in COLV rabbits compared with that observed in control rabbits, at the different days studied (p < 0,01). Ultimately, the COLV rabbits at 210-day showed an intense expression of COLV in the bronchovascular interstitium, followed by a markedly up-regulation of COLV mRNA (p < 0.001) as compared to controls. This study provides evidence for pulmonary vascular endothelial cell dysfunction in rabbits with COLV-induced SSc. The findings of this study reinforce the role of endothelial cells as a primary pathogenic event in SSc. The COLV model may provide insight into the pathogenesis of human disease

Descrevemos modelo original de sinovite experimental em coelhos imunizados com colágeno V com escasso processo inflamatório, intenso remodelamento matricial e vasculite. Analise morfológica e bioquímica foi realizada em coelhas Nova Zelândia (N=20) imunizadas com colágeno do tipo V, comparadas com controles. Foi observado o aumento dos colágenos I, III e V, oclusão do lúmen vascular e escasso processo inflamatório. A análise bioquímica confirmou a fibrose com aumento da síntese de colágeno. Nós postulamos que as alterações sinoviais descritas neste modelo foram conseqüência das particularidades do colágeno V, que promove manifestações imunológicas e clínicas semelhantes à esclerodermia / We described an original model of experimental synovitis in rabbits immunized with collagen V with scant cellular infiltration, intense matrix remodeling and vasculitis. Morphological and biochemical analysis were realized in New Zealand female rabbits (N=20) immunization with type V collagen, compared with control rabbits. It was observed increase of collagen I, III and V, vascular lumen occlusion and scant inflammatory process. Biochemical analysis confirmed the fibrosis with increased synthesis of collagen. We postulate that synovial changes described in this model are consequence of collagen V particularities, which promotes immunologic and clinical manifestations similar to scleroderma

O objetivo do presente estudo é o de comparar funcionalmente ehistologicamente o efeito terapêutico da glicosamina em relação a diacereína no modelo experimental de artrose em ratos. Trinta ratos Wistar foram submetidos a meniscectomia medial do joelho direito. Dez animais receberam 50mg/kg/dia de diacereína a partir do 3o até o 7o mês de pósoperatório (PO), dez animais receberam 40mg/kg/dia de glicosamina e dez animais não receberam nenhuma medicação. Todos foram sacrificados no 7o mês PO. Foram medidos os ângulos de extensão máxima de cada joelho. A análise histológica com hematoxilina-eosina e alcian blue foi feita de cada um dos côndilos tibiais e femorais. Todos os joelhos operados apresentaram amplitude de extensão do joelho mais limitada que o lado contra-lateral (p=0,001), porém os que receberam diacereína apresentavam menor rigidez (p=0,005). Histologicamente, o modelo experimental levou a uma artrose de leve a moderada estatisticamente diferente do joelho contra-lateral não operado (p=0,001). Já os joelhos dos ratos que fizeram uso das medicações não apresentaram diferenças significativas (p=0,3) entre aqueles que tomaram glicosamina e os que fizeram uso da diacereína. As diferenças entre os joelhos operados medicados e não medicados também não foram estaticamente diferentes. Conclusões: O uso terapêutico da diacereína e glicosamina diminuiu a rigidez articular e retardou a progressão da artrose. A diacereína atuou melhor na mobilidade articular do que a glicosamina, porém não houve diferença estatística entre as duas drogas no controle da degeneração articular / The purpose of this study is to compare, based on a functional and histological analysis, the therapeutic effects of glucosamine as compared to diacerhein in an experimental model of arthritis in rats. Thirty Wistar rats were submitted to a medial meniscectomy of the right knee. Ten animals received 50 mg/kg/day of diacerhein from the third through seventh postoperative (PO) months, ten animals received 40mg/kg/day of glucosamine and ten animals received no medication at all. All of these animals were sacrificed during the seventh PO month. The maximum angle of each knee extension was measured. A histological analysis was carried out by hematoxilin-eosin and alcian blue staining of each of the tibial and femoral condyles. All the operated knees presented a more limited range of extension than the non-operated knees (p=0.001), however, the animals that received diacerhein presented less stiffness (p=0.005). Histologically, the experimental model caused a light to moderate arthritis statistically different from the other non-operated knee (p=0.001). No significant differences (p=0.3) were detected between the knees of the rats medicated with glucosamine and those that received diacerhein. The operated medicated knees and non-operated knees also showed no statistical differences. Conclusion: The therapeutic use of diacerhein and glucosamine decreased joint stiffness and delayed the progression of the arthritis. The diacerhein had a more positive effect on joint mobility than the glucosamine, even though there was no statistical difference between the two drugs in controlling the degeneration of the joint

Introdução: a pressão intracraniana pode ser monitorada por meio de vários métodos que podem ser invasivos ou não invasivos. A ultrassonografia do nervo óptico é uma técnica não invasiva que permite mensurar a bainha deste nervo e detectar possíveis variações no seu diâmetro. O nervo óptico faz parte do sistema nervoso central de maneira contígua e é envolvido por uma bainha. Sendo assim, elevações ou reduções da pressão intracraniana podem ser transpostas à bainha deste nervo com consequente variação do seu diâmetro. Essas variações podem ser observadas pela ultrassonografia. Objetivo: determinar, por meio da ultrassonografia, o diâmetro da bainha do nervo óptico normal e avaliar os possíveis efeitos das drogas neste diâmetro durante a indução anestésica em suínos hígidos com pressão intracraniana normal. Métodos: foram selecionados 118 suínos híbridos saudáveis (64 fêmeas) de aproximadamente 20 kg e faixa etária similar. Todos os suínos foram submetidos à anestesia geral e foram devidamente monitorados. Os animais foram divididos em três grupos conforme os medicamentos utilizados: Grupo A: utilizando medicamento pré-anestésico xilazina e quetamina; Grupo B: utilizando xilazina (X), quetamina (Q) mais Propofol (P), e Grupo C: anestesiados com xilazina, quetamina e tiopental [tionembutal (T)]. As coletas das medidas nos três grupos foram feitas pelo aparelho de ultrassom em triplicata de cada olho, com os animais em posição laterolateral. Resultados: não houve diferenças estatisticamente significantes entre sexo e peso. O Diâmetro médio da bainha do nervo óptico em ambos os lados de cada grupo foram de 0,394±0,048 cm (X/Q), 0,407±0,029 cm (X/Q/P) e 0,378±0,042 cm (X/Q/T). Considerando todos os grupos, o diâmetro da bainha do nervo óptico variou de 0,287 cm a 0,512 cm (média 0,302 ± 0,039 cm). Houve diferenças estatisticamente significativas entre os grupos P e T (P > T, p = 0,003). Não foram detectadas diferenças significativas quando outros grupos foram comparados entre si. Conclusão: o diâmetro médio da bainha do nervo óptico, considerando todos os grupos, foi 0,302 ± 0,039 cm (0,287 cm - 0,512 cm) e 0,344 cm ± 0,048 cm nos indivíduos sedados apenas com X/Q / Introduction: the intracranial pressure can be monitored by various methods that may be invasive or non-invasive. Ultrasonography of the optic nerve is a technique non-invasive that allows measurement of the nerve sheath and detection of possible variations in its diameter noninvasively. The optic nerve is part of the central nervous system continuously and is surrounded by a sheath. Thus, with the increase or reduction of intracranial pressure, it can be transposed to the sheath of this nerve with consequent variation of its diameter. These variations can be observed through the ultrasound image. Objective: determine the normal optical nerve sheath diameter and to evaluate the possible effects of drugs on optical nerve sheath diameter during anesthetic induction in healthy pigs with normal intracranial pressure through ultrasound image. Methods:118 Healthy hybrid piglets from (64 female) the weighing approximately 20 kg each and of similar ages. All pigs underwent general anesthesia and were duly monitored. The animals were divided into three groups according to the medications used. Group A received preanesthetic xylazine and ketamine; Grupo B received xylazine, ketamine and propofol, and Grupo C received xylazine, ketamine, and thiopental (thionembutal). Measurements in the three groups were done by the ultrasound device in triplicate of each eye from the left and right sides. Results: There were no statistically significant differences between sex and weight. The mean optical nerve sheath sizes on both sides in each group were 0.394±0.048 cm (X/K), 0.407±0.029 cm (X/K/P) and 0.378±0.042 cm (X/K/T). Considering all the groups, the diameter of the optic nerve sheath varied from 0.287-0.512 cm (mean of 0.302±0.039 cm). There were statistically significant differences between the groups P and T (P > T, p=0.003). No statistically significant differences were detected when other groups were compared each other. Conclusion: The mean diameter of the optic nerve sheath considering all groups was 0.302±0.039 cm (0.287-0.512 cm) and 0.394±0.048 cm in the subjects only sedated with X/K

INTRODUÇÃO: Os macrófagos são células inflamatórias importantes no desenvolvimento e progressão do enfisema pulmonar e dependendo do estímulo do microambiente estas células podem ser diferenciadas em fenótipos M1 ou fenótipo M2. Os macrófagos de fenótipo M1 são reconhecidos como pró-inflamatórios enquanto que os macrófagos de fenótipo M2 são reconhecidos pela ação anti-inflamatória. O objetivo deste estudo foi caracterizar a polarização dos macrófagos em fenótipos M1 e M2 nos diferentes modelos experimentais de indução de enfisema pulmonar. MÉTODOS: foram utilizados camundongos C57BL/6 machos e foram divididos em quatro grupos experimentais, Grupo PPE (Elastase Pancreática de Porco): Animais que receberam instilação intranasal de 50 microL de PPE (0,667UI) com eutanásia no 28° dia; Grupo Salina: Animais que receberam instilação intranasal de 50 microL de soro fisiológico (SF) (0,9%) com eutanásia no 28° dia; Grupo Fumo: Animais que foram expostos à fumaça de cigarro durante 30 minutos, duas vezes por dia, 5 dias por semana consecutivos durante 12 semanas e Grupo Controle: Animais que foram mantidos no biotério e expostos ao ar ambiente por 12 semanas. Após eutanásia, os pulmões foram removidos, fixados em formaldeído e em seguida, foram feitos cortes para análise do intercepto linear médio (Lm) e contagem de células positivas para os macrófagos totais (MAC-2), interferon-gama (IFN)-gama e fator de necrose tumoral (TNF)-alfa, interleucina (IL)-10, transformação do fator do crescimento (TGF)-beta, metaloproteases (MMP)-9 e -12, no parênquima pulmonar. Pela técnica de ELISA foi avaliado no lavado broncoalveolar (LBA): IFN-gama e IL-12 (fenótipo M1) e IL-4, IL-10 e IL-13 (fenótipo M2). Pela técnica de PCR em tempo-real foi avaliada a expressão gênica para cluster of differentiation 68 (CD68), fator de regulação de interferon (Irf)-5, quimiocinas- CXC (CXCL9) e (CXCL10), o receptor de interleucina (IL)-12b e óxido nítrico sintase (iNOS) (fenótipo M1) e Irf-4, resistin-like molecule alpha (Fizz1), chitinase-3-like protein 3 (Ym1) e arginina-1 (Arg1) (fenótipo M2). RESULTADOS: Nossos resultados demonstraram aumento dos espaços aéreos distais e consequente presença de enfisema pulmonar nos dois grupos avaliados. Observamos redução da expressão gênica para CD68 no grupo PPE em comparação ao seu controle e tendência a aumento da expressão deste gene para o grupo Fumo comparado ao seu controle. A avaliação da expressão gênica para marcadores M1 revelou aumento para CXCL9 e CXCL10 nos grupos PPE, aumento de CXCL9 e redução de CXCL10 no grupo Fumo e redução de IL-12b no grupo Fumo comparados aos seus respectivos controles. A avaliação da expressão gênica para fenótipo M2, demonstrou diminuição de Arg1 e Fizz1 nos grupos PPE comparado ao salina. Pela técnica de ELISA encontramos uma redução de IL-4, IL-10 e IL-13 nos grupos PPE e aumento no grupo Fumo de IL-10, ambos comparados aos seus respectivos controles. Para a contagem de células positivas MAC-2, encontramos o aumento de macrófagos totais nos dois modelos avaliados, para marcadores de fenótipo M1, encontramos aumento de TNF-alfa e IFN-gama nos dois modelos avaliados, para marcadores de fenótipo M2, encontramos aumento de TGF-beta nos dois modelos de enfisema pulmonar avaliado. Entretanto para interleucina-10 encontramos uma redução no grupo PPE e aumento no grupo Fumo, ambos comparados aos seus respectivos controles. CONCLUSÃO: Demonstramos que os modelos induzidos pela exposição a fumaça de cigarro e instilação elastase resultaram em diferentes polarizações de macrófagos devido às diferenças do microambiente e que o modelo experimental de exposição à fumaça de cigarro foi o que melhor representou as características fisiológicas observadas em pacientes DPOC / Macrophages are important inflammatory cells on development and progression of pulmonary emphysema. Depending on microenvironment stimuli, these cells can differentiate into M1 or M2 phenotypes. Macrophages M1 phenotype play proinflammatory role whereas macrophages M2 phenotype play anti-inflammatory role. Our objective was to characterize the polarization of macrophages in M1 and M2 phenotypes in different experimental models of pulmonary emphysema induction. Male C57BL/6 mice were used and divided into four experimental groups. Group PPE (Porcine Pancreatic Elastase): Animals received intranasal instillation of 50 microL of PPE (0.677 IU) with euthanasia on the 28th day; Saline Group: Animals which received intranasal instillation of 50 microL SF (0.9%) with euthanasia on the 28th day; Cigarette Smoke Group: Animals exposed to cigarette smoke for 30 minutes, twice a day, 5 days a week for 12 weeks and Control Group: Animals that were exposed to ambient air for 12 weeks. After euthanasia, the lungs were removed, fixed in formaldehyde and then sectioned for analysis of the mean linear intercept (Lm) and counting of cells positive for total macrophages (MAC-2), interferon gamma (IFN-gama), factor Tumor necrosis (TNF-alfa), interleukin (IL)-10, transforming growth factor beta (TGF)-beta, matrix metalloproteinases- (MMP)-9 e -12 in the lung parenchyma through the immunohistochemistry technique. In order to evaluate the expression of proteins we used ELISA technique for IFN-gama and IL-12 (M1 phenotype) and IL-4, IL-10 and IL-13 (M2 phenotype) by bronchoalveolar lavage (BAL). They were also evaluated by gene expression analysis by the Real Time-PCR technique for cluster of differentiation 68 (CD68), interferon regulating factor (Irf-5), chemokines CXC (CXCL9) and (CXCL10), subunit beta of interleukin 12 (IL-12b) and nitric oxide synthase (iNOS) and for M2 phenotypes were analyzed Irf4, found in inflammatory zone- 1(Fizz1), chitinase type-1 (Ym1) and arginine-1 (Arg1) molecules. RESULTS: Our results demonstrated an increase in distal air spaces and consequent presence of pulmonary emphysema in both groups. Also, we observed reduction of CD-68 gene expression in PPE group compared to his control and tendency to increase the expression on Cigarette Smoke group (CS) compared to his Control. The evaluation of gene expression for M1 markers revealed an increase for CXCL9 and CXCL10 in the PPE groups, increase of CXCL-9 and reduction of CXCL10 on CS group and reduction of IL-12b on CS group compared to their respective controls. The evaluation of gene expression for M2 phenotype demonstrated a decrease of Arg1 and Fizz1 in PPE groups compared to saline group. By ELISA technique, we found reduction of IL-4, IL-10 and IL-13 on PPE groups, while we did not observe statistical difference in CS group, both compared to their respective controls. The TNF-alfa and IFN-gama positive cells counts showed an increase for both groups in the two models evaluated, for M2 phenotype we found an increase for TGF-beta in both emphysema models whereas for IL-10 we found a reduction in PPE group and increase on CS group, both compared to their respective controls. CONCLUSIONS: We demonstrated that the models induced by exposure to cigarette smoke and elastase instillation resulted in different macrophages polarizations due to differences in the microenvironment and that the experimental model of exposure to cigarette smoke was the one that best represented the physiological characteristics observed in COPD patients

Background and Purpose: Primary nocturnal enuresis (PNE) is a heterogeneous disorder with various underlying pathophysiological mechanisms. Results of our recent studies focused on the relationship of bladder function, sleep and brain function demonstrated a simultaneous occurrence of bladder and brain dysfunction in children with severe refractory PNE. We therefore proposed to use an animal model with altered bladder function to evaluate if abnormalities in bladder function induce functional derangement in brainstem micturition centers and/or sleep-arousal centers. / Materials and methods: In general, the study was divided in to 6 parts. Male Wistar rats (~ 1.5 months) were used for the study. / Study I: Establishment of animal model —— Male Wistar rats (200-220 g) underwent either Sham surgery or surgical reduction of bladder volume (RBV). Animals were used for further Cystometry, EEG, MRS and Cognitive function studies 4-5 weeks postoperatively. / Study II: Conventional Fill Cystometry (CFC) to evaluate bladder functional changes in response to surgical bladder volume reduction —— Twenty-four rats (RBV=12, SHAM 12) were used for the study. CFC was performed under conscious condition for evaluating the functional changes in response to surgical bladder capacity reduction. / Study III: Radiotelemetered EEG study to assess the impact of bladder dysfunction on sleep architecture and cortical arousals in rats —— Twenty-four rats (RBV=12, SHAM 12) were used for the study. Radiotelemeters were implanted in both groups 4 weeks post-operatively. The EEG biopotential and bladder pressure were monitored for 48 hours. Sleep architecture and cortical arousals were then evaluated manually. / Study IV: Evaluation of cognitive function following surgical bladder volume reduction —— Ninety eight rats (RBV=50, SHAM =48) were used for the study. / Morris Water Maze task: A circular plastic translucent pool half-filled with 26 ± 2ºC water, was used in the Morris Animals were given 9 consecutive training (2/day) sessions of Morris Water Maze (MWM) at 4 weeks postoperatively. / 8-arm Radial Maze: Food pellets were randomly placed inside each arm of the maze and the rats were allowed to explore the maze freely for 5 minutes. The rat was allowed to explore the maze for 5 minutes. Total time spent in each arm, total distance traveled in the maze was recorded. / Study V: Magnetic Resonance Spectroscopy to detect functional changes in brain in response to bladder dysfunction elicited by surgical bladder volume reduction —— Proton magnetic resonance spectroscopy was employed to examine brain metabolic changes in 24 rats (RBV=12, SHAM=12). Single voxel 1 H MRS experiments were performed using a 7 T MRI scanner. MR spectra were then processed using the jMRUI software. / Phase VI: Enzyme -linked immunosorbent assay for the assessment of associated changes in neurotransmitters —— Animals were euthanized after MRS study and brain samples were collected. Serotonin and dopamine levels were assessed in 10 mg of tissue extracts from brainstem and cortex, with ELISA kits. / Results: Study I: Bladder reduction surgery did not affect the increase in body weight post -operatively. Average body weight of the RBV and the sham groups were 340.2 ± 47.2 g and 340.5 ± 67.9 g respectively at 4 weeks post operatively. / Study II: Compared to sham group, the maximum cystometric capacity in animals with RBV was remarkably reduced at week 4 (0.78 ± 0.12 ml vs. 1.46 ± 0.22 ml, RBV vs. Sham respectively; p<0.005). Moreover, maximum detrusor pressure during voiding was significantly increased in RBV group at week 4 post operatively (32.4± 2.14 vs.23.27±1.2 5 cm H2O, RBV vs. Sham respectively). / Study III: Light non-repaid eye movement sleep occurred significantly more in RBV rats compared to sham group (61.8% vs 35%). Deep sleep and rapid eye movement sleep occurred significantly less in RBV group compared to that of sham group (30.7% vs 53.4%). / Study IV: Results showed that the RBV group used a significantly longer latency to locate the platform compared to Sham group (24.4s vs 17.19s, RBV vs. Sham respectively, p<0.001).. Moreover, significantly more animals from the RBV group could not complete the visit of the 8 arms of radial maze than that of the sham group. / Study V: Seven metabolites were detected and quantified. The results demonstrated significant changes in the lactate (Lac) metabolism in some specific regions of rat brain. At 4 weeks post - operatively, level of lactate significantly decreased in the hippocampus (43%, P<0.001) cingulate and retrosplenial cortex (29%, p<0.05) of RBV rats compared to that of sham rats. / Study VI: Results demonstrated a significant increase in Serotonin level in the brainstem of RBV rats compared to that of SHAM rats (23.726 + 0.88 ng/ml vs. 1.88 + 0.302 ng/ml). Dopamine levels decreased significantly in brainstem samples of RBV group compared to sham group (2.85 + 0.10 ng/ml vs. 6.85 + 0.84 ng/ml). / Conclusion: Surgical bladder volume reduction of bladder capacity can induce functional changes in the central nervous system. An alteration of the sleep architecture occurred in response to surgical reduction of bladder volume in rats, suggesting that there exists a potential for central consequences of bladder dysfunction. Bladder disorder chronically altered brain energy metabolism. Furthermore, bladder disorder altered the central neurotransmission in the brainstem and cortex. The finding of bladder dysfunction induced significant impairments in cognitive function in RBV rats, suggesting that the alteration in brain energy metabolism may contribute to the behavioral and attention problems, impaired learning and cognitive performance. / 研究背景： 原發性夜間遺尿症（PNE）是一種異質性疾病，涉及多種潛在的病理生理機制。我們最近的研究主要集中在膀胱功能，睡眠和腦功能的關係，結果顯示膀胱和腦功能障礙同時出現在患有嚴重難治性的PNE的兒童。因此，我們建議採用一種已改變膀胱功能的動物模型來評估膀胱功能異常會否引起腦幹排尿中心和/或睡眠 - 覺醒中心的功能紊亂 / 研究工具和方法： 研究被分成6個部分。雄性Wistar大鼠（約1.5個月）被用於研究。 / 研究I： 動物模型的建立 —— 雄性Wistar大鼠（200-220克），會先接受假手術或手術降低膀胱容量（RBV）。手術後4至5週，動物會進行進一步的膀胱測壓，腦電圖，MRS和認知功能研究。 / 研究II： 以常規填充膀胱測壓（CFC）評估減少膀胱容量手術對膀胱功能的變化 —— 二十四隻大鼠（RBV=12，對照=12）被用於研究。 CFC是用以評估在有意識的條件下，膀胱因膀胱容量減少的手術而引起的功能變化。 / 研究III： Radiotelemetered腦電圖研究，以評估在大鼠膀胱功能失調對睡眠結構和皮質覺醒的影響 —— 二十四隻大鼠（RBV=12，對照=12）被用於研究。膀胱容量減少的手術4週後，Radiotelemeters被植入在兩個組別的大鼠，並監測其腦電生物電勢和膀胱內壓48小時，然後手動評估睡眠結構和皮層覺醒。。 / 研究IV： 評估在膀胱容量減少的手術後對認知功能的影響 —— 103個大鼠（RBV=56，對照= =47）被用於研究。 / Morris水迷宮任務： 一個圓形的塑料半透明池盛載半滿的水，溫度介乎26 - ±2℃，手術4週後，該池被用在莫里斯動物進行連續9次Morris水迷宮（MWM）培訓（每天2次）。 / 八臂迷宮： 食物顆粒被隨機放置在迷宮的每個臂內，大鼠可以自由地探索迷宮5分鐘。大鼠被允許探索迷宮5分鐘。在每個手臂所用的總時間，以及在迷宮行走的總距離都會被記錄。 / 研究V： 以磁共振波譜檢測膀胱容量減少的手術所引起的膀胱功能障礙對腦功能的改變 —— 以質子磁共振波譜研究24隻大鼠腦內的代謝變化(RBV=12，對照==12）。以7 T MRI掃描儀進行磁共振波譜實驗，然後使用jMRUI軟件處理MR譜。 / 第六期： 以酶聯免疫吸附測定法評估神經遞質的相關變化 —— 動物在進行MRS研究後實施安樂死，並收集其腦樣品。從腦幹和皮層提取10毫克組織提取物，使用ELISA試劑盒，以評估羥色胺和多巴胺水平。 / 結果： 研究I： 膀胱容量減少手術並沒有影響體重增加。手術4週後，利巴韋林和對照實驗組的平均體重分別為340.2±47.2克和340.5±67.9克。 / 研究II： 相比起對照實驗組的動物，RBV組的最大膀胱容量顯著降低（0. 0.78 ± 0.12毫升對1.46±0.22毫升），排尿頻率顯著增加（2.53±0.30 對.0.53±0.05/hr）。此外，排尿時最大逼尿肌壓力亦顯著升高（32.0.8±2.19 比.20.37±1.2 5厘米水分子） / 研究III： 相比起對照實驗組的動物，光非快速動眼期睡眠顯著地較多發生於RBV大鼠身上（61.8％對35.6％），深層睡眠和快速動眼期睡眠顯著地較少發生在RBV組（32.3％對52.8％） / 研究IV： 結果表明，RBV組使用了顯著較長的時間來定位平台（24.4s vs. vs.17.19s）。而且，在RBV組，顯著地較多動物無法完成行走8臂的放射狀迷宮。 / 研究V： 進行檢測和定量七種代謝物。結果顯示乳酸（LAC）代謝在大鼠大腦的某些特定區域出現顯著變化。在手術4週後，相比起對照實驗組的動物，RBV組大鼠在海馬體（43％，P <0.001），扣帶和夾肌皮質（29％，P <0.05）的乳酸水平均顯著減少。 / 研究VI： 結果顯示RBV大鼠腦幹的血清素水平較對照實驗組的顯著增加（23.726+0.88納克/毫升與1.88±0.302ng/ml）。RBV大鼠腦幹的多巴胺水平則較對照實驗組的顯著下降（2.850.10納克/毫升與6.85+0.84毫微克/毫升）。 / 結論： 外科膀胱容量減少可誘導中樞神經系統的功能變化。以外科手術減少膀胱容量的大鼠亦引起睡眠結構改變，這顯示膀胱功能障礙對中樞有潛在影響。膀胱疾病長期改變大腦的能量代謝。此外，膀胱疾病亦改變了在腦幹和大腦皮層的中樞神經遞質傳遞。研究發現膀胱功能障礙顯著地損害RBV大鼠的認知功能，顯示改變大腦的能量代謝亦可導致行為和專注力的問題，從而損害學習和認知能力。 / Yeung, Chung Kwong. / Thesis Ph.D. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 199-230). / Abstracts also in Chinese. / Title from PDF title page (viewed on 14, September, 2016). / Yeung, Chung Kwong. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.

Dorsal root ganglia (DRG) cell preparations are commonly used to study the properties of sensory neurons in relation to nociception. A typical DRG cell preparation contains both neurons and glial cells, and in addition to a conventional supportive role of glial cells, an increasing volume of literature has reported interactions between neurons and accompanying glial cells. A typical mixed DRG cell preparation can be separated into a neuron-enriched cell fraction and a preparation of purified glial cells. Using these purified cell fractions, we can study the relative contributions and interactions between neurons and glial cells in regulating neurite outgrowth and adenylyl cyclase-dependent cell signalling activity in vitro. / From our previous studies, pretreating DRG cell cultures with pertussis toxin (PTx) caused neurite retraction over a period of 2 h following the initial stimulus of removal from incubator. The purpose of the current study was to investigate whether this PIx-dependent response was specific to anyone of the three subpopulations of DRG neurons. Interestingly, no neurite retraction response was observed in enriched DRG cultures, including cultures enriched with isolectin B4 (IB4)-positive neurons or IB4-negative neurons. Addition of glial cells or conditioned medium from glial cells to IB4-negative cultures was necessary to restore the PTx-dependent neurite retraction response, which was then only observed in large diameter proprioceptive neurons. To conclude, glial cells constitutively release factor/s that stimulate neurite retraction in larger diameter neurons, and is counterbalanced by neuroprotective Gilo protein signalling pathway. / From our studies, we have provided evidence of bidirectional interactions between neurons and glial cells, with glial cells regulating neurite outgrowth and neurons regulating adenylyl cyclase activity in glial cells. These findings reveal the properties of glial cells in regulating neurite outgrowth and in producing prostanoid-stimulated responses. Moreover, our fmdings provide foundation to understand complex neuron-glia interactions in vivo which will eventually help to overcome obstacles in promoting neurite regeneration and in controlling pain. / In a parallel study, we proved that hyperalgesic agents such as prostaglandin E2 (PGE2) and the prostacyclin (PGI2) mimetic (cicaprost) stimulate cAMP production in DRG cell culture via EP4 and IP receptors, respectively. These prostanoids were presumed to act only on the neurons in typical mixed cell cultures, but since we had acquired purified glial cell preparation, we tested for involvement of glial cells in measurement of agonist-stimulated cAMP production. Interestingly, a purified glial cell cultures also produced EP4 and IP-dependent responses. The expression of EP4 and IP receptors by DRG glia was further confirmed by the detection of EP4 and IP-like immunoreactivity and mRNA. Moreover, these agonist-stimulated responses were greatest in the glial cell preparation, and surprisingly weakest in the neuron-enriched cell cultures. Furthermore, the presence of neurons significantly inhibited both EP4 and IP receptor-dependent signalling in glial cells, but was without effect on forskolin (agonist-independent) stimulation of adenylyl cyclase. In order to characterize this neuron-glia interaction, we tested the adenylyl cyclase activities in glial cell cultures which were treated with conditioned medium derived from neurons or were separated from physical contact with neurons plated on transwell membrane. These studies further suggest that the neuron-glia interactions were dependent on both soluble factors and cell-cell contact. / Ng, Kai Yu. / Adviser: Helen Wise. / Source: Dissertation Abstracts International, Volume: 73-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 152-172). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.