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A epilepsia atinge cerca de 1% da população mundial, sendo que aproximadamente 30% desses pacientes não respondem ao tratamento medicamentoso. Por sua vez, as células-tronco representam uma esperança de tratamento da epilepsia, visto que têm grande capacidade de proliferação, diferenciação e regeneração de tecidos, podendo restaurar circuitos neurais e restabelecer a excitabilidade neuronal fisiológica. O objetivo deste estudo é verificar se as células mononucleares da medula óssea (CMMO) apresentam potencial terapêutico no controle das crises epilépticas e do dano neuronal progressivo induzido pela epilepsia experimental. Os animais foram injetados com lítio-pilocarpina (127 mg/kg e 60 Mg/kg i.p., respectivamente) para indução de status epilepticus (SE). As crises comportamentais foram classificadas de acordo com a escala de Racine e a duração do SE foi controlada com diazepam (10 mg/kg, i.p., 90 minutos). Os animais controle receberam solução salina. Após 22 dias, o total dos animais foi dividido em quatro grupos: Pilocarpina; Pilocarpina + CMMO, Salina e Salina + CMMO. Os grupos CMMO receberam transplante de células da camada mononuclear da medula óssea, obtidas de camundongos EGFP C57BL/6, via veia caudal (107 células, 200L), e os demais salina. Os animais tratados com pilocarpina foram monitorados por vídeo durante sete dias pré-transplante e outros catorze dias após o procedimento, para observação e computação de crises espontâneas recorrentes (CERs). Ainda, 45 dias depois da injeção das células os animais foram avaliados na tarefa do labirinto aquático de Morris (LAM) e a seguir na tarefa de reconhecimento de objetos, e logo após utilizou-se o teste do eletrochoque máximo para avaliação do limiar convulsivo. Decorridos sete meses do transplante os animais foram sacrificados e foram coletados os hipocampos direito e esquerdo, e amostras de cerebelo, bulbo olfatório, coração, pulmão e fígado para análise da presença de EGFP por PCR. Nossos resultados demonstram que os animais tratados com pilocarpina que receberam injeção de CMMO têm melhor desempenho no LAM quando comparados com o grupo pilocarpina. Esta melhora foi significativa durante o primeiro e último dias de treino, e também durante o teste em todos os parâmetros avaliados: latência, número de cruzamentos e permanência no quadrante alvo. Ainda, as CMMO reduziram o número de crises. Entretanto, na tarefa de reconhecimento de objetos e no teste do eletrochoque máximo não há diferença entre os animais epilépticos tratados ou não com CMMO. Finalmente, não foram detectadas bandas correspondentes à EGFP em nenhuma das amostras estudadas. Nos últimos anos, estudos que buscam tratamentos baseados em células-tronco para as mais diversas doenças neurodegenerativas foram vistos com muito interesse. Este tipo de tratamento pode ser útil também no tratamento da epilepsia crônica, dado o potencial que estas células têm de, independentemente do mecanismo, restaurar o micro ambiente neuronal e re-estabelecer a excitabilidade neuronal fisiológica. Palavras-chave: Epilepsia, células-tronco, testes comportamentais. / Epilepsy affects 1% of the world population and 30% of these patients are refractory to medication now available. Stem cells host hope in the treatment of epilepsy. Given their ability to proliferate, differentiate and regenerate tissues they could fix neural circuits and reestablish the physiological excitability of neurons. This study aimed to verify the therapeutic potential of bone marrow mononuclear cells (BMMC) on seizure control and on progressive neuronal loss induced by experimental epilepsy. Experimental status epilepticus (SE) was induced by lithium-pilocarpine injection (127 mg/kg; ip and 60 mg/kg; ip respectively). Seizures were scored by Racine’s scale. The duration of SE was controlled with diazepan (10mg/kg; ip; 90 minutes after SE onset). Control animals received saline other than pilocarpine. Twenty-two days after SE, rats were randomly assigned into four groups: Pilocarpina; Pilocarpine+BMMC; Control and Control+BMMC. BMMC groups received cell transplantation (obtained from EGFP C57BL/6 mice) via tail vein (107 cells, 200L). The other groups received saline in the same volume. Pilocarpine-treated animals were monitored for the presence of spontaneous seizures for 21 days (7 prior to cell transplant and 14 afterwards).Forty-five days after transplant rats underwent cognitive evaluation in the object recognition task and the Morris water maze (MWM), followed by the maximal electroshock test to evaluate seizure threshold. Rats were sacrificed seven months after transplantation. The hippocampi, cerebellum, olfactory bulb, and samples of the heart, lung and liver were collected in order to verify the presence of EGFP using PCR. Our results demonstrate that pilocarpine-treated rats injected with BMMC perform better in the MWM when compared to pilocarpine only. This difference was significant in the first and last training days and during the probe trial, when we evaluated the escape latency, time in target quadrant and number of crossings. In addition, seizure frequency was reduced by BMMC. Despite that, in the object recognition task and in the maximal electroshock test no difference was found between epileptic rats treated with BMMC or saline. Finally, we didn’t detect the presence of EGFP in any of the analyzed samples. During the last years much has been done to study the application of stem cells in several neurodegenerative diseases. This kind of approach can also be valid in the treatment of chronic epilepsy, given these cells have the potential of, whichever the mechanism might be, restore the neuronal micro environment and reestablish neuronal physiological excitability.

A epilepsia atinge cerca de 1% da população mundial, sendo que aproximadamente 30% desses pacientes não respondem ao tratamento medicamentoso. Por sua vez, as células-tronco representam uma esperança de tratamento da epilepsia, visto que têm grande capacidade de proliferação, diferenciação e regeneração de tecidos, podendo restaurar circuitos neurais e restabelecer a excitabilidade neuronal fisiológica. O objetivo deste estudo é verificar se as células mononucleares da medula óssea (CMMO) apresentam potencial terapêutico no controle das crises epilépticas e do dano neuronal progressivo induzido pela epilepsia experimental. Os animais foram injetados com lítio-pilocarpina (127 mg/kg e 60 Mg/kg i.p., respectivamente) para indução de status epilepticus (SE). As crises comportamentais foram classificadas de acordo com a escala de Racine e a duração do SE foi controlada com diazepam (10 mg/kg, i.p., 90 minutos). Os animais controle receberam solução salina. Após 22 dias, o total dos animais foi dividido em quatro grupos: Pilocarpina; Pilocarpina + CMMO, Salina e Salina + CMMO. Os grupos CMMO receberam transplante de células da camada mononuclear da medula óssea, obtidas de camundongos EGFP C57BL/6, via veia caudal (107 células, 200L), e os demais salina. Os animais tratados com pilocarpina foram monitorados por vídeo durante sete dias pré-transplante e outros catorze dias após o procedimento, para observação e computação de crises espontâneas recorrentes (CERs). Ainda, 45 dias depois da injeção das células os animais foram avaliados na tarefa do labirinto aquático de Morris (LAM) e a seguir na tarefa de reconhecimento de objetos, e logo após utilizou-se o teste do eletrochoque máximo para avaliação do limiar convulsivo. Decorridos sete meses do transplante os animais foram sacrificados e foram coletados os hipocampos direito e esquerdo, e amostras de cerebelo, bulbo olfatório, coração, pulmão e fígado para análise da presença de EGFP por PCR. Nossos resultados demonstram que os animais tratados com pilocarpina que receberam injeção de CMMO têm melhor desempenho no LAM quando comparados com o grupo pilocarpina. Esta melhora foi significativa durante o primeiro e último dias de treino, e também durante o teste em todos os parâmetros avaliados: latência, número de cruzamentos e permanência no quadrante alvo. Ainda, as CMMO reduziram o número de crises. Entretanto, na tarefa de reconhecimento de objetos e no teste do eletrochoque máximo não há diferença entre os animais epilépticos tratados ou não com CMMO. Finalmente, não foram detectadas bandas correspondentes à EGFP em nenhuma das amostras estudadas. Nos últimos anos, estudos que buscam tratamentos baseados em células-tronco para as mais diversas doenças neurodegenerativas foram vistos com muito interesse. Este tipo de tratamento pode ser útil também no tratamento da epilepsia crônica, dado o potencial que estas células têm de, independentemente do mecanismo, restaurar o micro ambiente neuronal e re-estabelecer a excitabilidade neuronal fisiológica. Palavras-chave: Epilepsia, células-tronco, testes comportamentais. / Epilepsy affects 1% of the world population and 30% of these patients are refractory to medication now available. Stem cells host hope in the treatment of epilepsy. Given their ability to proliferate, differentiate and regenerate tissues they could fix neural circuits and reestablish the physiological excitability of neurons. This study aimed to verify the therapeutic potential of bone marrow mononuclear cells (BMMC) on seizure control and on progressive neuronal loss induced by experimental epilepsy. Experimental status epilepticus (SE) was induced by lithium-pilocarpine injection (127 mg/kg; ip and 60 mg/kg; ip respectively). Seizures were scored by Racine’s scale. The duration of SE was controlled with diazepan (10mg/kg; ip; 90 minutes after SE onset). Control animals received saline other than pilocarpine. Twenty-two days after SE, rats were randomly assigned into four groups: Pilocarpina; Pilocarpine+BMMC; Control and Control+BMMC. BMMC groups received cell transplantation (obtained from EGFP C57BL/6 mice) via tail vein (107 cells, 200L). The other groups received saline in the same volume. Pilocarpine-treated animals were monitored for the presence of spontaneous seizures for 21 days (7 prior to cell transplant and 14 afterwards).Forty-five days after transplant rats underwent cognitive evaluation in the object recognition task and the Morris water maze (MWM), followed by the maximal electroshock test to evaluate seizure threshold. Rats were sacrificed seven months after transplantation. The hippocampi, cerebellum, olfactory bulb, and samples of the heart, lung and liver were collected in order to verify the presence of EGFP using PCR. Our results demonstrate that pilocarpine-treated rats injected with BMMC perform better in the MWM when compared to pilocarpine only. This difference was significant in the first and last training days and during the probe trial, when we evaluated the escape latency, time in target quadrant and number of crossings. In addition, seizure frequency was reduced by BMMC. Despite that, in the object recognition task and in the maximal electroshock test no difference was found between epileptic rats treated with BMMC or saline. Finally, we didn’t detect the presence of EGFP in any of the analyzed samples. During the last years much has been done to study the application of stem cells in several neurodegenerative diseases. This kind of approach can also be valid in the treatment of chronic epilepsy, given these cells have the potential of, whichever the mechanism might be, restore the neuronal micro environment and reestablish neuronal physiological excitability.

A epilepsia atinge cerca de 1% da população mundial, sendo que aproximadamente 30% desses pacientes não respondem ao tratamento medicamentoso. Por sua vez, as células-tronco representam uma esperança de tratamento da epilepsia, visto que têm grande capacidade de proliferação, diferenciação e regeneração de tecidos, podendo restaurar circuitos neurais e restabelecer a excitabilidade neuronal fisiológica. O objetivo deste estudo é verificar se as células mononucleares da medula óssea (CMMO) apresentam potencial terapêutico no controle das crises epilépticas e do dano neuronal progressivo induzido pela epilepsia experimental. Os animais foram injetados com lítio-pilocarpina (127 mg/kg e 60 Mg/kg i.p., respectivamente) para indução de status epilepticus (SE). As crises comportamentais foram classificadas de acordo com a escala de Racine e a duração do SE foi controlada com diazepam (10 mg/kg, i.p., 90 minutos). Os animais controle receberam solução salina. Após 22 dias, o total dos animais foi dividido em quatro grupos: Pilocarpina; Pilocarpina + CMMO, Salina e Salina + CMMO. Os grupos CMMO receberam transplante de células da camada mononuclear da medula óssea, obtidas de camundongos EGFP C57BL/6, via veia caudal (107 células, 200L), e os demais salina. Os animais tratados com pilocarpina foram monitorados por vídeo durante sete dias pré-transplante e outros catorze dias após o procedimento, para observação e computação de crises espontâneas recorrentes (CERs). Ainda, 45 dias depois da injeção das células os animais foram avaliados na tarefa do labirinto aquático de Morris (LAM) e a seguir na tarefa de reconhecimento de objetos, e logo após utilizou-se o teste do eletrochoque máximo para avaliação do limiar convulsivo. Decorridos sete meses do transplante os animais foram sacrificados e foram coletados os hipocampos direito e esquerdo, e amostras de cerebelo, bulbo olfatório, coração, pulmão e fígado para análise da presença de EGFP por PCR. Nossos resultados demonstram que os animais tratados com pilocarpina que receberam injeção de CMMO têm melhor desempenho no LAM quando comparados com o grupo pilocarpina. Esta melhora foi significativa durante o primeiro e último dias de treino, e também durante o teste em todos os parâmetros avaliados: latência, número de cruzamentos e permanência no quadrante alvo. Ainda, as CMMO reduziram o número de crises. Entretanto, na tarefa de reconhecimento de objetos e no teste do eletrochoque máximo não há diferença entre os animais epilépticos tratados ou não com CMMO. Finalmente, não foram detectadas bandas correspondentes à EGFP em nenhuma das amostras estudadas. Nos últimos anos, estudos que buscam tratamentos baseados em células-tronco para as mais diversas doenças neurodegenerativas foram vistos com muito interesse. Este tipo de tratamento pode ser útil também no tratamento da epilepsia crônica, dado o potencial que estas células têm de, independentemente do mecanismo, restaurar o micro ambiente neuronal e re-estabelecer a excitabilidade neuronal fisiológica. Palavras-chave: Epilepsia, células-tronco, testes comportamentais. / Epilepsy affects 1% of the world population and 30% of these patients are refractory to medication now available. Stem cells host hope in the treatment of epilepsy. Given their ability to proliferate, differentiate and regenerate tissues they could fix neural circuits and reestablish the physiological excitability of neurons. This study aimed to verify the therapeutic potential of bone marrow mononuclear cells (BMMC) on seizure control and on progressive neuronal loss induced by experimental epilepsy. Experimental status epilepticus (SE) was induced by lithium-pilocarpine injection (127 mg/kg; ip and 60 mg/kg; ip respectively). Seizures were scored by Racine’s scale. The duration of SE was controlled with diazepan (10mg/kg; ip; 90 minutes after SE onset). Control animals received saline other than pilocarpine. Twenty-two days after SE, rats were randomly assigned into four groups: Pilocarpina; Pilocarpine+BMMC; Control and Control+BMMC. BMMC groups received cell transplantation (obtained from EGFP C57BL/6 mice) via tail vein (107 cells, 200L). The other groups received saline in the same volume. Pilocarpine-treated animals were monitored for the presence of spontaneous seizures for 21 days (7 prior to cell transplant and 14 afterwards).Forty-five days after transplant rats underwent cognitive evaluation in the object recognition task and the Morris water maze (MWM), followed by the maximal electroshock test to evaluate seizure threshold. Rats were sacrificed seven months after transplantation. The hippocampi, cerebellum, olfactory bulb, and samples of the heart, lung and liver were collected in order to verify the presence of EGFP using PCR. Our results demonstrate that pilocarpine-treated rats injected with BMMC perform better in the MWM when compared to pilocarpine only. This difference was significant in the first and last training days and during the probe trial, when we evaluated the escape latency, time in target quadrant and number of crossings. In addition, seizure frequency was reduced by BMMC. Despite that, in the object recognition task and in the maximal electroshock test no difference was found between epileptic rats treated with BMMC or saline. Finally, we didn’t detect the presence of EGFP in any of the analyzed samples. During the last years much has been done to study the application of stem cells in several neurodegenerative diseases. This kind of approach can also be valid in the treatment of chronic epilepsy, given these cells have the potential of, whichever the mechanism might be, restore the neuronal micro environment and reestablish neuronal physiological excitability.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Demyelinating diseases are severe owing to the destruction of myelin sheaths present in the central (CNS) and peripheral (PNS) nervous system. The demyelination may occur in infectious and compressive diseases of the spinal cord in dogs. The experimental model of demyelination and remyelination by Ethidium Bromide (EB) promotes impairment of locomotor activities similar to those observed in multiple sclerosis (MS). The purpose of this study was to investigate the effect of flavonoid quercetin on behavioral tests, on cholinergic neurotransmission, on parameters of oxidative stress in blood, on cholinesterase activity in blood and Acetylcholinesterase (AChE) activities in lymphocytes of rats submitted to the EB experimental demyelination model and to review cases of the atlantoaxial subluxation in the neurological records of the Veterinary Hospital. In the first paper, fourteen dogs were diagnosed as affected by atlantoaxial subluxation in dogs and the condition was more frequent in toy breeds under twenty-four month old years. The main cause found for the instability was agenesis of the odontoid process. Clinical signs ranged from cranial cervical pain to non-ambulatory tetraparesis. The surgical treatment demonstrated to be efficacious. The predominant time of recovery was 30-60 days after surgery. No correlation was found between the duration of clinical signs before surgery and the time of recovery. In the experimental study, Wistar rats were randomly distributed into four groups (20 animals per group): Control (pontine saline injection and treatment with ethanol), Querc (pontine saline injection and treatment with quercetin), EB (pontine 0.1% EB injection and treatment with ethanol), and EB+Querc (pontine 0.1% EB injection and treatment with quercetin). The animals of the groups Querc and Querc + EB were treated once daily with quercetin (50mg/kg) diluted in 25% ethanol solution (1 ml / kg) and the animals of the control groups and EB were treated once daily with 25% ethanol solution (1 ml / kg). Two stages were observed: phase of demyelination with a peak on day 7 and phase of remyelination with a peak on day 21 post-inoculation of EB. In the first manuscript, the behavioral tests (the beam walking test, foot fault test and Inclined plane test), AChE activity and lipid peroxidation in the brain structures (pons, cerebellum, hippocampus, hypothalamus, striatum and cortex) were measured. Quercetin promoted earlier locomotor recovery, prevented the inhibition of AChE activity and the increase of lipidic peroxidation. In a second manuscript, parameters of oxidative stress in blood, cholinesterase activity in blood and AChE activities in lymphocytes were measured. The experimental demyelination model by EB promoted alteration in AChE activity of non neural cells, and also modified the oxidative stress parameters in the blood. In addition, quercetin was able to modulate AChE activity and of the antioxidant enzymes, as well as reduces lipid peroxidation in demyelinated rats by EB. These results may contribute to a better understanding of the neuroprotective role of quercetin and the importance of an antioxidant diet in humans and in animals, and the therapeutic potential this flavonoid in demyelination diseases, such as ME in humans, distemper in dogs, as well as in spinal cord compression (atlantoaxial subluxation). / As doenças desmielinizantes são uma grave consequência da destruição das bainhas de mielina presentes no sistema nervoso central (SNC) e periférico (SNP). A desmielinização pode ocorrer tanto em doenças infecciosas como compressivas da medula espinhal em cães. O modelo experimental de desmielinização e remielinização pelo brometo de etídio (BE) promove a diminuição da atividade locomotora semelhantes às observadas na doença de esclerose múltipla (EM). O objetivo deste estudo foi investigar o efeito do flavonoide quercetina nos testes comportamentais, na neurotransmissão colinérgica, na atividade das colinesterases no sangue, na atividade da acetilcolinesterase em linfócitos e nos parâmetros de estresse oxidativo no sangue, durante os eventos de desmielinização e remielinização em ratos submetidos ao modelo experimental pelo BE e realizar levantamento de dados sobre cães com diagnóstico de subluxação atlantoaxial atendidos no hospital veterinário universitário. No primeiro artigo, foram diagnosticados 14 cães com subluxação atlantoaxial, sendo as raças de pequeno porte com idade inferior a 24 meses as mais acometidas. A principal causa da instabilidade foi a agenesia do processo odontóide do áxis e os sinais clínicos variaram desde hiperestesia cervical até tetraparesia não ambulatória. O tratamento cirúrgico demonstrou ser eficaz com tempo de recuperação predominante de 30-60 dias após a cirurgia, não existindo relação deste com a duração dos sinais clínicos. Para o estudo experimental, ratos Wistar foram distribuídos aleatoriamente em quatro grupos (20 animais por grupo): Controle (injeção de solução salina e tratamento com etanol), Querc (injeção de solução salina e tratamento com quercetina), BE (injeção de BE a 0,1% e tratamento com etanol), e BE + Querc (injeção de BE a 0,1% e tratamento com quercetina). Os animais dos grupos Querc e Querc + BE foram tratados uma vez ao dia com quercetina (50mg/kg) diluída em solução de etanol a 25% na dose de 1 ml/kg. Os animais dos grupos controle e BE foram tratados uma vez ao dia com solução de etanol a 25% na dose de 1 ml/kg. As fases avaliadas foram no pico de desmielinização (dia 7) e no pico de remielinização (dia 21), pós-inoculação de BE. No primeiro manuscrito, os testes comportamentais (teste do beam walking, teste do foot fault e teste do plano inclinado), a atividade da AChE e peroxidação lipídica nas estruturas encefálicas (hipotálamo, hipocampo, cerebelo, córtex, estriado e ponte) foram avaliadas nos dias 7 e 21 pós-inoculação de BE. O tratamento com quercetina promoveu maior velocidade de recuperação locomotora, preveniu a inibição da atividade de AChE e o aumento da peroxidação lipídica em ratos submetidos à desmielinização pelo BE. No segundo manuscrito, os parâmetros de estresse oxidativo no sangue, a atividade das colinesterases no sangue e a atividade da AChE nos linfócitos foram avaliados nos dias 7 e 21 pós-inoculação de BE. O modelo de desmielinização experimental por BE promoveu alteração na atividade da AChE no sangue total e linfócitos, e modificou os parâmetros das enzimas antioxidantes, bem como reduziu a peroxidação lipídica em ratos submetidos à desmielinização pelo BE. Estes resultados podem contribuir para uma melhor compreensão do papel neuroprotetor da quercetina, enfatizando a importância deste antioxidante na dieta humana e animal, e do potencial terapêutico deste composto em doenças desmielinizantes tais como a esclerose múltipla, a cinomose, bem como doenças traumáticas (subluxação atlantoaxial e DDIV, entre outras).

Spinal cord injury is a very significant clinical as well as social problem with extensive consequences, affecting the patient and also his/her family. Great efforts have been devoted to searching for an effective treatment, which would improve their situation. This thesis evaluated the effects of the natural compound curcumin on spinal cord injury using an experimental balloon compression model. Male Wistar rats were randomized into two groups following the lesion induction, namely vehicle- or curcumin-treated. The behavioral recovery was evaluated using a set of locomotor and sensory tests and a histological and imunohistochemical analysis was performed. The qPCR method was used to observe the expression of some genes related to regeneration and immune response. It was demonstrated that curcumin improved locomotor recovery after the spinal cord injury, particularly in the early stages. Morphometric analysis of the gray and white matter sparing didn't confirm any differences between the two groups. Nevertheless, the glial scar formation was significantly reduced around the central part of the lesion in the curcumin treated group and also the NF-κB activity was substantially inhibited. The gene expression analysis demontrated downregulation of Gfap and Rantes genes and upregulation of the Irf5 gene...

Number of studies report that even when experimental animals are subjected to the exact same conditions, they differ in their behaviour. If these differences were stable in time and across several experimental procedures, we could talk about personality. This diploma thesis studies inter-individual differences in behaviour of laboratory rats (Long Evans strain) in a series of experiments conducted in early ontogeny and in adult age. Apart from analysing inter-individual differences in behaviour and personality of experimental animals, this thesis has two main aims. The first aim is assessing stability of inter-individual differences in behaviour throughout ontogeny. The second aim is to explore possible link between inter-individual differences in behaviour and performance in cognitive tests. We confirmed the existence of inter-individual difference in behaviour in laboratory rats. In this thesis we were, however, not able to assess personality of experimental animals. The differences in behaviour were best described by behaviour in Open field test and Elevated plus maze test. Our results also show marked differences between successive trials of these experiments. We also report that performance in Active allothetic place avoidance is not linked to performance in Morris water maze, even though both...

We can notice the positive effects of sleep on many functions of our organism. For a long time we have observed the interconnection between sleep and memory and today we already know, that different sleep phases correlate with an improvement of different memory types. One of the hypotheses, that explain the positive effect of sleep on strengthening of the memory representations, is its irreplaceable active role in the process of memory consolidation. The memory consolidation of episodic type in animals, which processes memories into events with time and space context, could according to this theory occur due to two phase sleep process, in which each phase has a specific role. The theoretical part of this thesis will familiarize the reader with the problematic of organization of time and space in our brain, and introduce him to the foundations of electroencephalography (EEG) and offer a detailed introduction into the discussed hypothesis of active sleep consolidation. The practical part is then focused on the confirmation of the already mentioned hypothesis through the combination of comparison of results from the behavioral task of 2 groups of animals with different sleep manipulation and of the analysis of EEG signal recorded during the experiment before and after the training. The behavioral task...

La maladie de Parkinson (MP) est une pathologie neurodégénérative associée principalement à une perte progressive de neurones dopaminergiques de la substance noire (SN) conduisant à une diminution de dopamine au niveau du striatum. Une des approches thérapeutiques expérimentales de la MP est la greffe de neurones dopaminergiques, non pas au niveau de la SN, mais directement dans la région cible, le striatum, et ceux avec des résultats variables. Dans cette étude, nous avons comparé en détail la récupération fonctionnelle suite à la transplantation de mésencéphale ventral (MV) fœtal provenant de souris exprimant la GFP sous le contrôle du promoteur de la tyrosine hydroxylase soit au niveau de la SN soit dans le striatum de souris adultes lésées unilatéralement à la 6-hydroxydopamine. Les conséquences anatomiques et fonctionnelles ont été analysées par des approches comportementales, électrophysiologiques et immunohistochimiques. Nos résultats montrent que les neurones greffés dans les deux emplacements envoient des projections vers le striatum. De plus, les deux types de greffes induisent une amélioration significative de la motricité ainsi que de l'activité des neurones du striatum. Toutefois, seule la greffe intranigrale a permis la restauration de la motricité fine des membres antérieurs et un retour à une excitabilité des neurones striataux à l’état basal. / Parkinson’s disease (PD) is a neurodegenerative disorder associated with a progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN), leading to a loss of dopamine in the striatum. One of the experimental therapeutic approaches in PD is the graft of DA neurons not in their ontogenic site, the SN, but directly into the target region, the striatum and those leads to variable results. In this study, we have analyzed in detail the functional outcome of fetal VM tissue expressing GFP under the control of a tyrosine hydroxylase promoter grafts placed either into the SN or striatum in unilaterally 6-hydroxydopamine lesioned adult mice. Anatomical and functional outcome were analyzed using behavioral, electrophysiological and immunohistochemical approaches. Our results show that transplanted neurons in both locations can survive and re-innervate the striatum. Furthermore, both grafts locations significantly restored motor performance and induced the recovery of striatal firing properties. However, only intranigral transplantation allows recovery of fine motor skills of previous members and efficiently normalized cortico-striatal responses.

Dissertation "The influence of corticosterone and corticoliberin on damage of the hippocampus and their relation to cognition" deals with the cognitive, behavioral and histological changes in experimental rat strain long-evans that closer describe the consequences of long-term continuous application of corticoliberin and/or corticosterone. Testing of the behavioral changes was divided into two phases. The first one - within three or fourweeks respectively administration of these hormones, therefore until their early effects - and the second phase - after four weeks of completion of the first phase at the time of the possible late effects. In the twelfth week the experimental animals were killed and in the group which had exogenously elevated corticosterone, the morphological changes in the hippocampus were monitored and measured. In all experimental groups alteration of behavior was observed. Histological and morphological changes in the brain we have found. Layout of experiments in two testing phases allowed differentiation of the early changes and the late and persistent changes. The arrangement of experiments allowed the choice of tests to compare not only individual effects of both hormones (corticoliberin and corticosterone) but also their coactioning and biological responses to them. Using a wider...