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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
731

Papel dos receptores 5-HT1A do Núcleo Mediano da Rafe na evocação da memória aversiva em ratos submetidos ao desamparo aprendido / Role of 5HT1-A receptors in the Raphe Median Nucleus in memorie evocation in rats submitted to learned helplessness

Abreu, Priscila Reis 03 June 2016 (has links)
A depressão se constitui um transtorno de alta frequência mundial, apresentando como um dos fatores etiológicos, a exposição a eventos estressores. Em termos neurobiológicos, vários trabalhos da literatura sugerem a importância das projeções serotoninérgicas que partem do Núcleo Mediano da Rafe (NMnR) para o Hipocampo Dorsal (HD) na adaptação ao estresse, a partir da desconexão das associações aversivas previamente aprendidas de suas consequências comportamentais. Assim, o presente trabalho apresenta como objetivo investigar o envolvimento dos receptores tipo 5-HT1a localizados no Núcleo Mediano da Rafe no processo de evocação de memórias aversivas. Para isso, ratos Wistar foram submetidos a cirurgia estereotáxica para a implantação de uma cânula-guia direcionada ao Núcleo Mediano da Rafe (NMnR). Passado o período de recuperação, os animais foram expostos a 40 choques inescapáveis (0,6mA; 10) (condição experimental) em uma caixa de vai-e-vem. Após 24 h, os animais receberam duas injeções intracerebrais de Salina (Sal), 8OHDPAT (DPAT; 3nmoles/0,2µl; agonista de 5-HT1aR) e/ou WAY100635 (WAY; 0,3nmoles/0,2µl; antagonista de 5-HT1aR) combinadas de forma a compor os seguintes grupos experimentais: Sal+Sal, WAY+Sal, Sal+DPAT e WAY+DPAT. Cinco minutos após as injeções, todos animais foram submetidos a uma sessão de teste, na qual foram apresentados 30 choques elétricos escapáveis (0,4mA; 10) nas patas, sinalizados por uma luz (15W; 20) que permanecia acesa durante a apresentação dos choques. Durante a sessão teste foram registrados a latência, o número de esquivas, fugas, falhas e o total de cruzamentos. Um grupo controle também foi realizado, sendo que os animais foram apenas colocados na caixa, sem exposição a choques inescapáveis, sendo testados 24 h após. Os resultados foram analisados pela ANOVA de medidas repetidas. Também foi calculada porcentagem de animais desamparados (%DA) em cada condição, analisada pelo teste do Qui-quadrado. A pré-exposição a choques inescapáveis levou ao desenvolvimento de desamparo aprendido, efeito esse não atenuado pelo tratamento com DPAT, o que pode ser observado na elevada %DA em todos os grupos. Por outro lado, na condição controle, observou-se uma reduzida %DA para todos os tratamentos. Nossos resultados sugerem que a ativação de receptores de tipo 5-HT1a do NMnR não está envolvida na evocação de memórias aversivas. / The depression is a high-frequency disorder in the world, having as one of the etiological causes the exposure to stressful events. In neurobiological terms, several studies of literature suggest the importance of serononinergic projections from the Median Raphe Nucleus for dorsal hipocampus in adaptation to stress, from the disconnection of aversive associations previously learnead of its behavioral consequences. Thus, the aim of this work is to investigate the involvement of 5-HT1a receptors located in the Median Raphe Nucleus in the aversive memory recall process. For this, Wistar rats were submitted to sterioc surgery for the implantation of a guided cannula aimed to MnRN. After the recovery period, the animals were exposed to 40 inescapable shocks (0,6mA; 10 \") (experimental condition) in a shuttled box. After 24 h, the animals received two intracerebral injections of saline (Sal), 8OHDPAT (DPAT; 3nmoles / 0,2l; 5-HT1aR agonist) and / or WAY100635 (WAY; 0,3nmoles / 0,2l; antagonist 5 -HT1aR) combined to compose the following groups: Salt + Salt + WAY Sal, Sal + DPAT and WAY + DPAT. Five minutes after the injections, all animals were submitted to a test session in which were presented 30 escapable eletric footshocks (0,4mA; 10 \") sinilized by a light (15W, 20\") which remained on during the presentation of shock. During the test session were recorded latency for these responses, the number of avoidance, escape, failure and the total crossings. A control group was performed, and the animals just placed in the shuttle box, without exposing inescapable shocks. The results were analyzed by repeated measures ANOVA. It was also calculated percentage of helpless animals (%HA) in each condition analyzed by chi-square test. The pre-exposure to inescapable shocks led to the development of learned helplessness, this effect does not attenuated by treatment with DPAT, which can be observed in high % of all groups. On the other hand, in the control condition, there is a reduced % of all treatments. Our results suggest that activation of 5-HT 1a of NMnR is not involved in the evocation of aversive memories.
732

Rôle du transporteur vésiculaire du glutamate de type 3 (VGLUT3) dans la réponse au stress hypoxique néonatal et la surdité DFNA25 / Atypical vesicular glutamate transporter type 3 (VGLUT3) function in the response to neonatal hypoxic stress, and the DFNA25 deafness

Miot, Stéphanie 24 February 2017 (has links)
Avant d'être libéré dans la fente synaptique, le glutamate est accumulé dans les vésicules présynaptiques par les transporteurs vésiculaires du glutamate (VGLUTs). Il existe 3 types de VGLUTs. VGLUT3 possède une distribution anatomique et des fonctions atypiques. Au sein du système nerveux central, VGLUT3 est exprimé dans des neurones glutamatergiques mais aussi non glutamatergiques, dans lesquels il assure les fonctions de co-transmission ou de synergie vésiculaire. On le retrouve notamment dans certains neurones sérotoninergiques du raphé. Au sein de l'oreille interne, VGLUT3 est l'unique VGLUT décrit dans les cellules ciliées internes (CCI). La sérotonine joue un rôle essentiel dans le contrôle respiratoire néonatal. En étudiant la respiration de souriceaux n'exprimant plus le VGLUT3, nous avons démontré le rôle de VGLUT3 dans l'adaptation au stress hypoxique néonatal. Une mutation de VGLUT3 a été mise en évidence dans une surdité humaine très proche cliniquement de la presbyacousie et appelée DFNA25. En étudiant le phénotype auditif de souris exprimant cette mutation, nous avons prouvé l'implication de cette mutation dans l'atteinte des CCI à l'origine de la surdité DFNA25. L'étude des processus biochimiques mis en jeu nous a permis d'envisager un rôle indirect de VGLUT3 dans l'activation de la mort autophagique, via la protéine Becline 1 et une possible interaction au sein de la voie de la Culline 3. L'ensemble de ce travail nous a permis de mettre en évidence un rôle de VGLUT3 dans l'adaptation aux conditions extrêmes telles que le développement néonatal ou le processus de vieillissement. Il ouvre de nouvelles perspectives sur les diverses fonctions des VGLUTs. / Before its release into synaptic cleft, glutamate is accumulated in presynaptic vesicles by vesicular glutamate transporters (VGLUTs). There are 3 types of VGLUTs. VGLUT3 presents atypical functions and anatomical distribution. In the central nervous system, VGLUT3 is expressed in glutamatergic and non glutamatergic neurons, in which it performs the co-transmission and the vesicular synergy. Particularly, we can observe VGLUT3 in serotoninergic neurons of raphe. In the inner ear, VGLUT3 is the unique VGLUT described in the inner hair cells (IHCs). Serotonin plays a key role in the neonatal respiratory control. By exploring the respiration of VGLUT3 knock out mice pumps, we have demonstrated the role of VGLUT3 in the response to neonatal hypoxic stress. One VGLUT3 mutation has been described in a human deafness clinically very close to presbycusis, the DFNA25 deafness. By studying the auditory phenotype of mice expressing this VGLUT3 mutation, we have proved the implication of this mutation in the IHCs impairment at the origin of DFNA25 deafness. Biochemical analysis have helped us to consider an indirect role of VGLUT3 in the autophagic death. Beclin 1 and a possible interaction between VGLUT3 and the Cullin3 pathways could be implicated. All of our results allowed us to highlight a role of VGLUT3 in the adaptation to extreme conditions like neonatal development or aging process. They open new perspectives on the various functions of VGLUTs.
733

Role of 5-HT₃ and tachykinin NK₁ receptors in drug-induced emesis and associated behaviours in the ferret and suncus murinus.

January 2003 (has links)
Lau Hoi Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 134-157). / Abstracts in English and Chinese. / PUBLICATIONS BASED ON WORK IN THIS THESIS --- p.I / ABSTRACT --- p.II / ACKNOWLEDGEMENTS --- p.VI / TABLE OF CONTENTS --- p.VIII / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- General Introduction --- p.1 / Chapter 1.2 --- Emesis --- p.3 / Chapter 1.2.1 --- Introduction --- p.3 / Chapter 1.2.2 --- Retching & Vomiting --- p.3 / Chapter 1.2.3 --- Nausea --- p.4 / Chapter 1.2.4 --- Motor Components of Emetic Reflex --- p.5 / Chapter 1.2.4.1 --- Pre-ejection Phase --- p.5 / Chapter 1.2.4.2 --- Ejection Phase --- p.5 / Chapter 1.2.4.3 --- Post-ejection Phase --- p.6 / Chapter 1.2.5 --- Components of Emetic Reflex --- p.6 / Chapter 1.2.5.1 --- Area Postrema (AP) --- p.6 / Chapter 1.2.5.2 --- Nucleus Tractus Solitarius (NTS) --- p.7 / Chapter 1.2.5.3 --- Vomiting Centre --- p.8 / Chapter 1.2.5.4 --- Vestibular System --- p.10 / Chapter 1.2.5.5 --- Abdominal Visceral Afferents --- p.10 / Chapter 1.2.5.6 --- Forebrain --- p.11 / Chapter 1.2.6 --- Neurotransmitters & Receptors --- p.12 / Chapter 1.2.7 --- Anti-emetics --- p.13 / Chapter 1.3 --- Models of Nausea --- p.16 / Chapter 1.3.1 --- Introduction --- p.16 / Chapter 1.3.2 --- Conditioned Taste Aversion --- p.18 / Chapter 1.3.3 --- Pica Behaviour --- p.20 / Chapter 1.3.4 --- Studies of the Involvement of Vasopressin --- p.21 / Chapter 1.3.5 --- Tachygastria --- p.24 / Chapter 1.3.6 --- Locomotor Activity --- p.26 / Chapter 1.4 --- Markers of Neuronal Activity --- p.27 / Chapter 1.4.1 --- General Comments --- p.27 / Chapter 1.4.2 --- c-fos Expression as a Marker of Neuronal Activity --- p.28 / Chapter 1.4.2.1 --- What is c-fos? --- p.28 / Chapter 1.4.2.2 --- Regulation of c-fos Expression --- p.30 / Chapter 1.4.2.2.1 --- Calcium Response Element --- p.31 / Chapter 1.4.2.2.2 --- Serum Response Element --- p.32 / Chapter 1.4.2.3 --- Types of Receptors Involved in c-fos Expression --- p.32 / Chapter 1.4.2.4 --- Feasibility of Using c-fos Expression as Marker of Cellular Activity --- p.36 / Chapter 1.4.2.5 --- Identification of Emetic Pathway by c-fos Immunohistochemistry --- p.36 / Chapter 1.5 --- Aims & Objectives --- p.37 / Chapter CHAPTER 2 --- METHODS --- p.42 / Chapter 2.1 --- Animals --- p.42 / Chapter 2.1.1 --- Ferrets --- p.42 / Chapter 2.1.2 --- Suncus murinus --- p.42 / Chapter 2.2 --- Measurement of Animal Behaviour --- p.43 / Chapter 2.2.1 --- Experiment Design --- p.43 / Chapter 2.2.2 --- Recording of Animal Behaviour --- p.43 / Chapter 2.2.3 --- Calibration of Equipment Used to Record Spontaneous Locomotor Activity --- p.44 / Chapter 2.2.4 --- Behaviour Recorded by the Observer --- p.45 / Chapter 2.3 --- Administration of Drugs --- p.46 / Chapter 2.3.1 --- Ferrets --- p.46 / Chapter 2.3.1.1 --- General Comments --- p.46 / Chapter 2.3.1.2 --- Drug Antagonism Studies --- p.47 / Chapter 2.3.2 --- Suncus murinus --- p.47 / Chapter 2.3.2.1 --- General Comments --- p.47 / Chapter 2.3.2.2 --- Dose-Response Studies --- p.48 / Chapter 2.3.2.3 --- Drug Antagonism Studies --- p.48 / Chapter 2.4 --- c-fos Expression Studies in Ferret Brainstems --- p.50 / Chapter 2.4.1 --- Animals and Anaesthesia --- p.50 / Chapter 2.4.2 --- Perfusion and fixation --- p.50 / Chapter 2.4.3 --- Dehydration of brains --- p.51 / Chapter 2.4.4 --- Embedding of tissue --- p.52 / Chapter 2.4.5 --- Sectioning --- p.52 / Chapter 2.4.6 --- Staining --- p.52 / Chapter 2.4.7 --- Antibodies used --- p.55 / Chapter 2.4.8 --- Positive Control Slides --- p.55 / Chapter 2.5 --- Experimental Design and Statistics --- p.56 / Chapter 2.5.1 --- Randomization of Treatments --- p.56 / Chapter 2.5.2 --- Statistics --- p.57 / Chapter 2.5.2.1 --- Ferrets --- p.57 / Chapter 2.5.2.2 --- Suncus murinus --- p.59 / Chapter 2.6 --- Drugs and Chemicals Used --- p.60 / Chapter 2.6.1 --- Drugs Used --- p.60 / Chapter 2.6.2 --- Chemicals Used --- p.62 / Chapter CHAPTER 3 --- RESULTS --- p.63 / Chapter 3.1 --- Ferret --- p.63 / Chapter 3.1.1 --- "The Effect of Ondansetron and CP-99,994 on Emesis and Locomotor Activity Changes Induced by Cisplatin in the Ferret" --- p.63 / Chapter 3.1.2 --- The Effect of Domperidone on Emesis and Locomotor Activity Changes Induced by Apomorphine in the Ferret --- p.69 / Chapter 3.1.3 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Apomorphine in the Ferret" --- p.74 / Chapter 3.1.4 --- c-fos Expression Studies in Ferret Brainstems --- p.79 / Chapter 3.1.4.1 --- Cisplatin-treated Ferrets --- p.79 / Chapter 3.1.4.2 --- Positive Control Slides --- p.84 / Chapter 3.2 --- Suncus murinus --- p.88 / Chapter 3.2.1 --- The Emetic Potential of Nicotine and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.88 / Chapter 3.2.2 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Nicotine in Suncus murinus" --- p.92 / Chapter 3.2.3 --- The Emetic Potential of Copper Sulphate and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.95 / Chapter 3.2.4 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Copper Sulphate in Suncus murinus" --- p.98 / Chapter 3.2.5 --- The Emetic Potential of Cisplatin and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.101 / Chapter 3.2.6 --- The Effect of Ondansetron on Emesis and Locomotor Activity Changes Induced by Cisplatin in Suncus murinus --- p.104 / Chapter 3.2.7 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Cisplatin in Suncus murinus" --- p.107 / Chapter 3.2.8 --- "The Effects of Ondansetron and CP-99,994 on Locomotor Activity in Suncus murinus" --- p.110 / Chapter CHAPTER 4 --- DISCUSSION --- p.113 / Chapter CHAPTER 5 --- GENERAL SUMMARY --- p.130 / REFERENCES --- p.134
734

Apports de la TEP dans l’imagerie moléculaire des récepteurs sérotoninergiques 5-HT1A et 5-HT7 / Contributions of PET in molecular imaging of 5-HT1A and 5-HT7 serotonin receptors

Lemoine, Laëtitia 04 March 2011 (has links)
Le système sérotoninergique, impliqué dans plusieurs pathologies du système nerveux central, peut être exploré in vivo par l’imagerie TEP (tomographie par émission de positons). La recherche et la validation préclinique de radiotraceurs ciblant spécifiquement les récepteurs sérotoninergiques est donc cruciale. Au cours de ce travail, nous nous sommes intéressés à deux récepteurs sérotoninergiques pour lesquels nous avons développé des outils moléculaires pour leur imagerie fonctionnelle: (i) les récepteurs 5-HT1A et (ii) les récepteurs 5-HT7. (i) Les récepteurs 5-HT1A sont parmi les récepteurs à sérotonine les mieux décrits à l’heure actuelle. Cependant, si des radiotraceurs TEP sont déjà disponibles, ceux-ci sont des antagonistes qui se fixent indifféremment aux récepteurs 5-HT1A, couplés aux protéines G et fonctionnels, et aux récepteurs 5-HT1A, découplés et non fonctionnels. Nous avons donc proposé une stratégie originale de développement d’un agoniste 5- HT1A radiomarqué au fluor afin d’accéder à une imagerie des récepteurs fonctionnels. Deux molécules, le F15599 et le F13714, initialement développées pour leurs propriétés antidépressives par un partenaire industriel, ont été radiomarquées au fluor 18 puis ont été évaluées in vitro, ex vivo et in vivo chez le rat et le chat. Nos résultats montrent que le [18F]F13714 permet de visualiser de manière inédite les récepteurs 5- HT1A couplés aux protéines G. (ii) Le deuxième axe de cette thèse concerne les récepteurs 5-HT7, de découverte récente et proposés comme cible thérapeutique antidépressive. A l’inverse des récepteurs 5-HT1A, les récepteurs 5-HT7 ne disposent pas encore de radiotraceur TEP. Notre approche a consisté à sélectionner, à partir du pharmacophore du récepteur, quatre structures d’antagonistes 5-HT7, synthétisées par un laboratoire partenaire de chimie : le 2FP3, le 4FP3, le 2FPMP et le 4FPMP. Nos études radiopharmacologiques in vitro, ex vivo et in vivo nous ont conduit à retenir un radiotraceur, le [18F]2FP3. À l’issue de ce travail de thèse CIFRE, nous pouvons donc proposer deux radiotraceurs TEP originaux, ouvrant des perspectives inédites d’imagerie moléculaires de la neurotransmission 5-HT1A et 5-HT7 et dont nous envisageons la poursuite du développement comme radiopharmaceutiques cliniques / The serotonergic system, implicated in several diseases of central nervous system, can be explored in vivo by PET imaging (positron emission tomography). The research and the preclinical validation of radiotracers that specifically target serotonin are crucial. In this work, we focused on two serotonin receptors for which we have developed molecular tools for functional imaging: (i) the 5-HT1A and (ii) the 5-HT7. (i) 5-HT1A receptors are among the serotonin receptors the best described at present. However, if PET radiotracers are already available, they are antagonists and bind either to 5-HT1A receptors, G protein-coupled and functional, and to 5-HT1A receptors decoupled and non-functional. We therefore proposed an original strategy to develop a 5-HT1A agonist labeled with fluorine to access imagery of functional receptors. Two molecules, the F15599 and F13714, initially developed for their antidepressant properties by an industrial partner, were radiolabeled with fluorine-18 and were evaluated in vitro, ex vivo and in vivo in rats and cats. Our results show that the [18F] F13714 may view in a new way the 5-HT1A G protein-coupled (ii) The second focus of this thesis for the 5-HT7, recently discovered and proposed as a therapeutic target antidepressant. Unlike the 5-HT1A, 5-HT7 receptors do not yet have PET radiotracer. Our approach was to select, from the pharmacophore of the receptor, four structures of 5-HT7 antagonists, synthesized by a lab partner in chemistry: the 2FP3, the 4FP3, the 2FPMP and 4FPMP. Our radiopharmacology in vitro, ex vivo and in vivo led us to retain a radiotracer, the [18F] 2FP3. At the conclusion of this thesis CIFRE, we can propose two originals PET radiotracers , opening new perspectives for molecular imaging of neurotransmission of 5-HT1A and 5-HT7 receptors and which we plan further development as clinical radiopharmaceuticals
735

"Modulação por mecanismos serotoninérgicos do comportamento exploratório de ratos submetidos ao teste e reteste no labirinto em cruz elevado" / "Modulation by serotonergic mechanisms of the exploratory behavior of rats submitted to the test and retest in the elevated plus-maze"

Lucas Albrechet de Souza 18 August 2006 (has links)
O labirinto em cruz elevado (LCE) é um dos testes de ansiedade mais empregados na atualidade. Uma característica intrigante desse modelo é a abolição dos efeitos ansiolíticos dos benzodiazepínicos como resultado de uma única experiência prévia no labirinto. Este fenômeno, chamado “one-trial tolerance” (OTT), tem recebido considerável atenção e dentre as diversas hipóteses sugeridas para explicá-lo, podemos citar uma alteração no estado emocional do animal, perda do conflito motivacional e habituação do comportamento exploratório. A descoberta de que benzodiazepínicos reduzem a atividade de neurônios serotoninérgicos, associada a resultados obtidos em testes de conflito que mostram que antagonistas serotoninérgicos podem causar efeitos ansiolíticos comparáveis aos benzodiazepínicos, levaram à noção de que a serotonina (5-HT) é o principal neurotransmissor envolvido na ansiedade. No entanto, com o uso de outros modelos animais, o envolvimento da 5-HT tem sido questionado, ao mesmo tempo em que outras aminas biogênicas, como a noradrenalina (NA), têm sido implicadas na modulação da ansiedade. Nesse estudo procedemos uma análise etofarmacológica de ratos tratados com o antagonista serotoninérgico cetanserina e os antidepressivos fluoxetina e desipramina submetidos ao teste e reteste no LCE. Esses antidepressivos aumentam os níveis sinápticos de 5-HT e NA, respectivamente. Além disso, foram medidas as concentrações plasmáticas de corticosterona - considerada um índice confiável de medo e estresse - de ratos expostos à sessão única ou repetida no LCE. As drogas administradas antes da reexposição ao labirinto não produziram efeitos ansiolíticos, replicando o fenômeno da OTT comumente associado aos benzodiazepínicos. Por outro lado, a cetanserina administrada antes da primeira sessão produziu um efeito ansiolítico, mas o tratamento subcrônica com fluoxetina e desipramina não alterou o comportamento exploratório dos animais no LCE. Ratos submetidos à sessão única ou repetida no labirinto apresentaram um aumento similar dos níveis plasmáticos de corticosterona, indicando que a reexposição ao LCE apresenta propriedades aversivas e a OTT deve estar mais relacionada à uma alteração no estado emocional do animal do que à habituação do comportamento exploratório. / The elevated plus-maze (EPM) is currently one of the most used test of anxiety. An intriguing feature of this model is the abolition of the anxiolytic effect of benzodiazepines by a single previous experience with the maze. This phenomenon, termed one-trial tolerance (OTT), has received considerable attention and among the several hypotheses suggested to explain it, we can listed a shift in the animal emotional state, lack of motivational conflict and exploratory behavior habituation. The discovery that benzodiazepines reduce the activity of serotonergic neurons, associated with results obtained in conflict tests showing that serotonergic antagonists may cause anxiolitic-like effects comparable to the benzodiazepines, has led to the notion that the serotonin (5-HT) is the most important neurotransmitter involved in the anxiety. Nevertheless, with the use of other animal models, the 5-HT involvement has been questioned, at the same time that other biogenic amines, such as noradrenalin (NA), have been implicated in the anxiety modulation. In this study, we carried out an ethopharmacological analysis of rats under treatment with the serotonergic antagonist ketanserin and the antidepressants fluoxetine and desipramine submitted to the test and retest in the EPM. These antidepressants increase the synaptic levels of 5-HT and NA, respectively. Besides, plasma corticosterone concentrations - considered a reliable index of fear and stress - of rats exposed once or twice to the EPM were measured. The drugs injected before the retest in the EPM did not produce anxiolytic effects, replicating the OTT phenomenon generally associated with the benzodiazepines. On the other hand, ketanserin injected before the first session produced an anxiolytic effect but the subchronic treatment with fluoxetine and desipramine did not change the exploratory behavior of the animals in the EPM. Naive and experienced rats show a similar increase in the plasma corticosterone levels when submitted to the EPM, indicating that the retest to EPM has aversive properties and the OTT may be more related to a change in the emotional state of the animal than to a habituation of the exploratory behavior.
736

Deple??o cerebral de serotonina durante o per?odo neonatal programa a homeostase metab?lica energ?tica e a express?o comportamental de ratos adultos. / Brain serotonin depletion during neonatal period programme energetic metabolic homeostasis and behavioral expression of adulthood rats

Moreira, Rodrigo Mencalha 28 August 2008 (has links)
Made available in DSpace on 2016-04-28T20:18:30Z (GMT). No. of bitstreams: 1 2008 - Rodrigo Mencalha Moreira.pdf: 2348355 bytes, checksum: 249dc9822a474bb30086d8952df6f1f2 (MD5) Previous issue date: 2008-08-28 / Brain serotonin (5-HT) depletion during the neonatal period lead a plastic cytoarchitecture change of the serotonergic system influencing directly several brain systems ontogeny development. This dissertation was aimed to elucidate the influence of brain 5-HT depletion during the neonatal period on the metabolic programming and the behavioral expression of adulthood rats. Brain 5-HT depletion was raised with the subcutaneous (s.c) administration of 100 mg. Kg-1 para-chlorophenylalanine (pCPA), a competitive inhibitor of the tryptophan hydroxylase enzyme, from the eighth at sixteenth post-natal days. In order to investigate the influence of pCPA on the subject metabolic programming, during and after treatment, the milk intake and body weight gain from the neonatal period to adulthood were evaluated. Furthermore, evaluating indirectly this influence on the energetic metabolism, the repercussions on the glycemic homeostasis through of the glycemia baseline measurements and under fasting in the adult rat were investigated. Around the ingestive behavior, baseline conditions paradigm and under fasting were made. In these experimental trials, water intake, ration, 2% sucrose and 0.3M NaCl were evaluated. Also, the 0.3 M NaCl intake after sodium depletion (furosemide 20mg. Kg-1, s.c) and water intake after hypertonic stimulus (1.0 M NaCl, s.c) were measured. The behavioral expression was evaluated through models involved with emotional-behavioral signals. In this analysis, the rat s anxiety status was investigated through of open field test, elevated plus-maze (EPM), social interaction and forced swimming. The results showed that treatment with pCPA reduces milk intake (P˂0.001) and therefore the body weight gain in the neonatal period (P˂0.001), claiming to be smaller until adulthood (P˂0.01). The glycemic homeostasis was also affected reflected in lower pCPA-male (P˂0.01) and pCPA-female (P˂0.001) levels after 24 hours of fasting. About to baseline intake, a higher pCPA-female sodium appetite (P˂0.05), related to a greater demand for 2% sucrose solution in both females (P˂0,001) were observed. Under fasting, a lower male-pCPA cumulative ration intake at 60 min (P˂0.05) and a higher female pCPA at 60 (P˂0.05) and 120 min (P˂0.01) were observed. Furthermore, after water deprivation, a higher pCPA-female cumulative water intake at 120 min (P˂0.05) compared with pCPA-male was rated. Was also observed a greater pCPA-male water intake at 120 and 180 min (P˂0.001) after hypertonic stimulus, however, it was not observed significant difference in the natriorexigenic responses in sodium depleted rats. In addition, pCPA male showed a evident anxiolytic activity in EPM test expressed by the higher time spent in the open arm (O.A) (P˂0.05), higher head-dipping in the O.A episodes (P˂0.001), less S.A.P. (P˂0.001) and grooming episodes (P˂0.01). Therefore, these results showed that 5-HT depletion during the neonatal period programme the energetic metabolic homeostasis and the behavioral expression of adulthood rats. / A deple??o cerebral de serotonina (5-HT) durante o per?odo neonatal acarreta uma altera??o pl?stica na citoarquitetura do sistema seroton?rgico influenciando diretamente o desenvolvimento ontog?nico de diversos sistemas cerebrais. Nesta disserta??o objetivou-se elucidar a influ?ncia da deple??o cerebral de 5-HT durante o per?odo neonatal sobre a programa??o metab?lica energ?tica e express?o comportamental de ratos adultos. A deple??o cerebral de 5-HT foi evocada com a administra??o subcut?nea (s.c) de 100 mg. Kg-1, de para-clorofenilalanina (pCPA), um inibidor competitivo da enzima triptofano hidroxilase, do oitavo ao d?cimo sexto dias p?s-natais. A fim de investigar a influ?ncia da pCPA, durante e ap?s o tratamento, sobre a programa??o metab?lica do indiv?duo, foram avaliadas a ingest?o de leite e o ganho de peso corporal do per?odo neonatal ? vida adulta. Ademais, avaliando indiretamente esta influ?ncia sobre o metabolismo energ?tico, foram investigadas as repercuss?es sobre a homeostase glic?mica atrav?s da mensura??o basal e sob jejum da glicemia do rato adulto. Em rela??o ao comportamento ingestivo foram realizados protocolos em condi??es basais e sob jejum. Nestes ensaios experimentais foram avaliadas as ingest?es de ?gua, ra??o, sacarose 2% e NaCl 0,3 M. Outrossim, foram mensuradas as ingest?es de NaCl 0,3 M ap?s deple??o de s?dio (furosemida 20mg. Kg-1, s.c) e de ?gua ap?s est?mulo hipert?nico (NaCl 1,0 M, s.c). A express?o comportamental foi avaliada atrav?s de modelos envolvidos com aspectos afetivo-comportamentais. Nesta an?lise, foi investigado o status de ansiedade dos ratos atrav?s dos testes de campo aberto, labirinto em cruz elevado (LCE), intera??o social e nata??o for?ada. Os resultados demonstraram que o tratamento com pCPA diminui a ingest?o de leite (P˂0,001) e conseq?entemente o ganho de peso corporal no per?odo neonatal (P˂0,001), sustentando-se menor at? a vida adulta (P˂0,01). A homeostase glic?mica tamb?m foi afetada refletida nos menores n?veis glic?micos em machos-pCPA (P˂0,01) e f?meas pCPA (P˂0,001) ap?s jejum alimentar de 24 horas. Em rela??o ?s ingest?es basais, foi observado um maior apetite por s?dio em f?meas-pCPA (P˂0,05), al?m de uma maior procura pela solu??o de sacarose 2% em ambas as f?meas (P˂0,001). Sob jejum alimentar, foi observada uma menor ingest?o cumulativa de ra??o em machos-pCPA aos 120 min (P˂0,05) e maior ingest?o em f?meas-pCPA aos 60 (P˂0,05) e 120 min (P˂0,01). Ademais, ap?s jejum h?drico, foi notada uma maior ingest?o cumulativa de ?gua em f?meas-pCPA aos 120 min (P˂0,05) em rela??o aos machos-pCPA. Observou-se ainda uma maior ingest?o de ?gua nos machos-pCPA aos 120 e 180 min (P˂0,001) ap?s est?mulo hipert?nico, por?m, n?o foi observada diferen?a significativa na resposta natriorexig?nica em ratos s?dio-depletados. Al?m disso, foi observada uma evidente atividade ansiol?tica no LCE expressa pelo maior tempo gasto no bra?o aberto (B.A) (P˂0,05), maior n?mero de epis?dios de head-dipping no B.A (P˂0,001), menos epis?dios de S.AP. (P˂0,001) e grooming (P˂0,01). Em resumo, estes resultados demonstram que a deple??o de 5-HT durante o per?odo neonatal programa a homeostase metab?lica energ?tica e a express?o comportamental de ratos adultos.
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Serotonina e glicogênio sintase quinase 3B em plaqueta de pacientes idosos com transtorno depressivo maior: efeito do tratamento com sertralina / Serotonin and glycogen synthase kinase 3B in platelets of elderly patients with major depressive disorder: sertraline effects

Helena Passarelli Giroud Joaquim 17 February 2012 (has links)
A depressão é o mais comum dos distúrbios afetivos. Afeta ao menos 10% da população idosa do Brasil. Nos idosos, alguns fatores ligados ao metabolismo parecem estar bastante relacionados a esse transtorno, como uma menor concentração de noradrenalina e serotonina (5-HT) e uma maior atividade da monoaminooxidase em relação a adultos jovens. Os inibidores seletivos da recaptação da serotonina (ISRS), principalmente a sertralina, são a primeira opção no tratamento da fase aguda e manutenção dos episódios depressivos em idosos. As plaquetas vêm sendo amplamente utilizadas como modelo para estudar na periferia alterações que ocorrem no sistema nervoso central. A 5-HT apesar de ser primordialmente expressa no cérebro, também pode ser encontrada em plaquetas. Este neurotransmissor está envolvido em inúmeros aspectos do funcionamento normal do cérebro desde a regulação do humor até a regulação hormonal. A deficiência nos níveis de 5-HT pode estar intimamente ligada a alguma anormalidade na atividade da glicogênio sintase quinase 3B(GSK3B). Esta enzima exerce funções no metabolismo celular que vão desde sobrevivência celular, metabolismo e processamento de proteínas, até processos cognitivos. A atividade da GSK3B é estreitamente regulada pela fosforilação. Fosforilação no sítio ser9 inativa a enzima, enquanto que a desfosforilação neste mesmo sítio ativa a enzima. Diversos estudos têm mostrado que a forma inativa da enzima exerce um efeito neuroprotetor. O objetivo do presente estudo foi verificar a influência do tratamento com sertralina, em pacientes idosos com diagnóstico de depressão maior, sobre a 5- HT e GSK3B após 3 e 12 meses de tratamento. A quantificação da 5-HT foi realizada por HPLC e da GSK3B plaquetária, pelos métodos de ELISA e blotting, que se revelaram equivalentes. Após um ano de tratamento encontramos uma diminuição da 5-HT plaquetária nos pacientes com depressão maior com relação aos níveis basais, bem como um aumento da forma total da enzima GSK3B (GSKT), uma diminuição da forma fosforilada (pGSK) e da razão entre pGSK e GSKT (rGSK). Quando comparados os níveis de GSK3B de pacientes tratados por um ano e controles, observamos uma maior expressão de GSKT em pacientes; enquanto a pGSK e rGSK se mostraram equivalentes. Pudemos observar, portanto, uma modulação da 5-HT e da GSK3B pelo uso de sertralina. Essa modulação pode indicar que a ação antidepressiva deste fármaco pode estar associada a essas vias de sinalização / Depression is the most common affective disorders. It affects at least 10% of the elderly population of Brazil. In the elderly, some factors related to metabolism appear to be closely related to this disorder, such as lower concentration of noradrenaline and serotonin (5-HT) and increased monoamine oxidase activity in relation to young adults. The selective serotonin reuptake inhibitors (SSRI), especially sertraline are the first choice in treating acute and maintenance of depressive episodes in the elderly. Platelets have been widely used as a model to study in peripheral changes that occur in Central Nervous System. Although 5-HT is primarily expressed in the brain, it can also be found in platelets. This neurotransmitter is involved in numerous aspects of normal brain function since the regulation of mood to the hormonal regulation. A deficiency in 5-HT levels may be closely related to an abnormality in glycogen synthase kinase 3B (GSK3B) activity. This enzyme plays several functions in cell metabolism, ranging from cell survival, metabolism and protein processing, to cognitive processes. The GSK3B activity is tightly regulated by phosphorylation. Phosphorylation on Ser9 site inactives the enzyme, whereas dephosphorylation in the same site actives the enzyme. Several studies have shown that the inactive form of the enzyme plays a neuroprotective effect. The objective of this study was to investigate the influence of sertraline in elderly patients diagnosed with major depression, on platelet 5-HT and GSK3B after 3 and 12 months of treatment. Quantification of 5-HT was performed by HPLC and GSK3B by ELISA and western blotting. The methods for platelet GSK3B determination showed to be equivalent. After one year of treatment we found a decrease of platelet 5-HT in patients with major depression relative to their baseline levels, as well as an increase in the total form of GSK3B enzyme (GSKT), a decrease in phosphorylated form (pGSK) and the ratio between pGSK and GSKT (rGSK). Comparing the levels of GSK3B of patients with one year of treatment and controls, we found a higher GSKT expression in patients; while pGSK and rGSK showed to be equivalent. Therefore we observed a modulation of 5-HT and GSK3B by sertraline. This modulation may indicate that the antidepressant action of this drug may be associated with these signaling pathways
738

Caracterização da ação molecular da Bunodosina 391, composto analgésico obtido da peçonha da anêmona Bunodosoma cangicum. / Characterization of the molecular mechanisms involved in the analgesic effect of Bunodosina 391 (BDS 391) obtained from Bunodosoma cangicum sea anemone venom.

Ferreira Junior, Wilson Alves 17 December 2010 (has links)
As anêmonas do mar utilizam um rico complexo protéico para capturar suas presas e para se defender de predadores. A peçonha, destes animais, contem neurotoxinas com ação em canais iônicos específicos e hemolisinas que atuam formando poros em membranas. No entanto, pouco se conhece sobre a atividade biológica de substâncias de baixo peso molecular isoladas da peçonha destes animais. Bunodosina 391 (BDS 391), um composto de baixo peso molecular isolado da peçonha da anêmona do mar Bunodosoma cangicum, apresenta atividade antinociceptiva periférica. Ensaios farmacológicos mostraram que a ação do BDS 391 é mediada pela ativação de receptores serotoninérgicos, histaminérgicos e pela abertura de canais de potássio. É interessante observar que o BDS 391 apresenta similaridade estrutural a 5-HT e histamina, o que torna de especial interesse a detecção do efeito antinociceptivo periférico para este composto. Os resultados obtidos nesse estudo poderão favorecer o melhor conhecimento sobre a fisiopatologia da dor e de seu controle, bem como o desenvolvimento de novos fármacos. / Animal toxins are directed against a wide variety of pharmacological targets, making them an invaluable source of ligands for studying the signaling pathways of pain and its control. Sea anemone venoms contain many biologically active compounds such as cytolysins (1820 kDa) and ion channel modulators (35 kDa). In addition, low molecular weight compounds have been isolated and identified in these venoms; however few studies have been carried out in order to determine the biological activity of such compounds. BDS 391 is a low molecular weight and non-peptidic compound purified from the Brazilian sea anemone Bunodosoma cangicum venom. Studies on the structure of BDS 391 have demonstrated that this compound is composed of a bromoindole group connected to histidine. Our recent data have indicated that BDS 391 administered by intraplantar route into the rat hind paw induces potent peripheral analgesia in models of acute and chronic pain. These study can to contribute to the better characterization of the pain pathway and your control.
739

Pharmaceutical salts of the antidepressants Paroxetine and Fluoxetine, selective serotonin reuptake inhibitors: crystal engineering, solid-state characterization and thermodynamic aspects / Sais farmacêuticos dos antidepressivos Paroxetina e Fluoxetina, inibidores seletivos de recaptação de serotonina: engenharia de cristais, caracterização de estado sólidos e aspectos termodinâmicos

Carvalho Júnior, Paulo de Sousa 30 September 2016 (has links)
The development of new solid forms of active pharmaceutical ingredients (API) is relevant both from fundamental as well as industrial perspectives. To this end, Crystal Engineering plays an ever-increasing important role in pharmaceutical sciences. Among the crystal engineering strategy, salt formation is the most important and implemented approach. The salt forms of API could be used to modulate and tuned the solubility and stability of API to provide optimal practical uses. Herein, we report pharmaceutical salts of two Selective Serotonin Reuptake Inhibitor antidepressants used in the treatment of depression and anxiety disorders, Paroxetine (PRX) and Fluoxetine (FLX). For this purpose, salt formers, supramolecular synthesis and crystallization protocols have been driven by the systematization of structural and supramolecular data of molecules and analogues from the Cambridge Structural Database. Paroxetine bromide hemihydrate ((PRXBr)0.5H2O), Paroxetine Nitrate hydrate (PRXNO3H2O) and two polymorphs of Fluoxetine Nitrate (FLXNO3) have obtained. All were characterized by a combination of techniques including Single Crystal X-ray Diffraction, Differential Scanning Calorimetry (DSC), Thermogravimetry analysis (TGA), Hot Stage Microscopy, Fourier transform infrared spectroscopy (IR) and solubility measurements. Since the hydration/dehydration process in APIs induces phase transitions that compromise its efficiency, the structural characterization of (PRXBr)0.5H2O help to understand its reversible dehydration process. Also, this study has implication in the understating of dehydration of isostructural PRX hydrochloride salt. Additionally, the (PRXNO3)H2O have shown the conformational flexibility and supramolecular diversity of PRX. On the other hand, the chirality of FLX is related to two nitrate salt polymorphs. A racemate and a non-centrosymmetric structure with independent enantiomers in the asymmetric unit were obtained for FLXNO3. Their packing have shown the existence of different racemic motifs, resulting in different enantiomer orientations The rare occurrence of racemic systems in non-centrosymmetric space groups becomes this event a noteworthy case. By their physicochemical properties, the polymorphs were monotropically related. The scientific contributions of this thesis show the diversity of the solid forms and define candidates to new antidepressants APIs solid formulations. / O desenvolvimento de novas formas sólidas de ingredientes farmacêuticos ativos (API) é relevante tanto numa perspectiva fundamental como industrial. Para tal, a Engenharia de cristais tem desempenhado um papel importante nas ciências farmacêuticas. Dentre as estratégias, a formação de sais é a abordagem mais importante e implementada. Os sais de APIs são capazes de modular e ajustar a solubilidade e a estabilidade, a fim de proporcionar uso prático. Nesta tese, são reportados sais de dois fármacos Inibidores Seletivos de Recaptação de Serotonina, consolidados no tratamento da depressão e distúrbios de ansiedade, a Paroxetina (PRX) e a Fluoxetina (FLX). Brometo de Paroxetina hemiidratado ((PRXBr)0.5H2O), Nitrato de Paroxetina hidratado (PRXNO3H2O) e polimorfos de Nitrato de Fluoxetina (FLXNO3), síntese e protocolos de cristalização foram cuidadosamente delineados, com base na sistematização de dados estruturais e supramoleculares das moléculas e seus análogos, depositados no Cambridge Structural Database. Todos os sais foram caracterizados por Difração de Raios-X por Monocristal, Calorimetria Explanatória Diferencial (DSC), Análise termogravimétrica (TGA), Termomicroscopia, Espectroscopia vibracional na região do infravermelho (IR) e solubilidade. Considerando que a hidratação/desidratação induz mudanças de fases que comprometem a eficiência do API, a caracterização do (PRXBr)0.5H2O auxiliou no entendimento do processo de desidratação reversível que ocorre para esse fármaco. Estas mudanças de fase resultam também em implicações sobre a compreensão do processo de desidratação do sal isoestrutural de cloreto de PRX hemiidratado. Além disso, por meio da elucidação estrutural do (PRXNO3)H2O, foi possível analisar a diversidade conformacional e supramolecular da PRX. Quanto à FLX, verificou-se que sua quiralidade está relacionada com seu polimorfismo. Um racemato e uma estrutura não centrossimétrica com dois enatiômeros independentes na unidade assimétrica foram obtidos para o FLXNO3. A comparação destas estruturas permitiu mostrar a existência de arranjos supramoleculares racêmicos, constituídos por diferentes orientações de enatiômeros. A rara ocorrência de sistemas racêmicos em grupos espaciais não-centrossimétricos tornou este evento um caso notável. A partir das propriedades físico-químicas, os polimorfos puderam ser monotropicamente relacionados. Os resultados desta tese trazem importantes contribuições científicas para diversidade de formas sólidas e também define novas formulações sólidas para utilização como antidepressivos.
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Estimulação do córtex motor e antinocicepção: envolvimento da via de analgesia serotonérgica descendente. / Motor cortex stimulation and antinociception: involvement of descending serotonergic pain pathway.

Lopes, Patrícia Sanae de Souza 20 September 2013 (has links)
A estimulação epidural do córtex motor (ECM) é eficaz no tratamento da dor neuropática refratária, porém seus mecanismos de ação ainda são incertos. Sabendo que a ECM ativa a via analgésica descendente em ratos, fomos investigar o efeito da ECM sobre os núcleos serotonérgicos descendentes, dorsal da rafe (NDR) e magno da rafe (NMR) e sobre os neurônios da coluna posterior da medula espinhal (CPME). Ratos Wistar, submetidos à ECM, foram avaliados no teste de pressão da pata e seus tecidos foram avaliados frente à imunorreatividade (IR) para Egr-1 (marcador de ativação neuronal), serotonina (5HT) e substância P (SP). A ECM induziu antinocicepção em 62% nos animais, não alterou a ativação do NDR, entretanto ativou o NMR (67%), quando comparado com ratos não estimulados. A ECM aumentou a IR-5HT em 75% no NDR e em 92% no NMR. Na CPME, a ECM inibiu os neurônios nociceptivos (48%), porém não interferiu com a IR-SP. Estes resultados sugerem que a ECM induz analgesia, em parte, via ativação do sistema serotonérgico descendente. / Motor cortex stimulation (MCS) is effective in the treatment of refractory neuropathic pain; however, its mechanisms of action remain unclear. Since the MCS activates the descending pain pathway in rats, we investigated the MCS effect on the descending serotonergic nuclei, dorsal raphe nucleus (DRN) and the magnus raphe nucleus (MRN) and also on the neurons of the dorsal horn of the spinal cord (DHSC). Wistar rats, submitted to MCS, were evaluated by paw pressure test and its tissues were evaluated by immunoreactivity (IR) to Egr-1 (neuronal activation marker), serotonin (5HT) and substance P (SP). MCS induced antinociception by 62% in animals, although did not modify the NDR activation; however, activated the MRN (67%), when compared to control groups. MCS increased the IR-5HT by 75% in the NDR and 92% in the MRN. In the DHSC, MCS inhibited the nociceptive neurons (48%), however did not change the IR-SP. These results suggest that MCS induce antinociception, partly, by the descending serotonergic pathway activation.

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