Navegando por Palavras-chave "Wistar rats"

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    Análise multielementar de tecidos biológicos do fígado de ratos Wistar machos adultos submetidos à superexposição de manganês (Mn)
    (Universidade Federal de São Paulo, 2021-02-26) Gonçalves, Ruan Ataulo Muniz [UNIFESP]; Barbosa, Renata de Faria [UNIFESP]; Perobelli, Juliana Elaine [UNIFESP]; http://lattes.cnpq.br/2047233951021632; http://lattes.cnpq.br/3663691702527038; http://lattes.cnpq.br/1829801883745835; Universidade Federal de São Paulo (UNIFESP)
    O manganês (Mn) é um elemento considerado essencial ao desenvolvimento corporal de todos os mamíferos, todavia, em níveis elevados, podem se tornar tóxicos (afetando as partes motoras e psíquicas). Os animais foram previamente intoxicados com duas doses diferentes de uma solução de Mn com período de exposição de 30(trinta) dias. Ratos machos adultos da linhagem Wistar com 83 dias de vida (n=24) foram distribuídos em três grupos experimentais (n = 8/grupo): C (grupo controle, recebeu apenas o veículo solução salina a 0,9%); Mn1 (recebeu cloreto de Mn, MnCl2, na dose de 5 mg/Kg de massa corpórea, diluído em solução salina a 0,9%) e Mn2 (recebeu cloreto de Mn, MnCl2, na dose de 15 mg/Kg de massa corpórea, diluído em solução salina a 0,9%). Assim, o objetivo desse estudo foi avaliar a absorção do Mn no fígado, e também verificar se há correlação entre a superexposição ao Mn com os níveis de outros metais presentes no fígado desses animais. As medições foram realizadas em duplicatas usando a técnica de Fluorescência de Raios X por Reflexão Total (TXRF) através do espectrômetro S2 PicoFox – Bruker, disponível no Instituto do Mar, UNIFESP/BS. Para as análises por TXRF, as amostras sólidas precisam ser suspensas em uma solução. Então, à 100 mg de massa seca e macerada do tecido do fígado adicionou-se 1,0 mL de triton (1%), seguida de 1,0 mL de água deionizada. Foi também adicionado o padrão interno: gálio, a fim de atender a metodologia para quantificação. No fígado dos ratos estudados encontramos Na, Cl, K, Ca, Cr, Mn, Fe, Cu, Zn, Se, Rb e Sr. A estatística usada foi o Anova One-Way seguido do teste Bonferroni com nível de significância de 0,05. Analisando os níveis de Mn no fígado, observamos que a intoxicação via manganês resultou em um acréscimo no fígado deste elemento. Além disso, a superexposição ao manganês gerou também um aumento estatisticamente significativo nos níveis de cálcio, sódio e zinco no grupo Mn2, intoxicados com 15mg/kg de manganês, em relação ao grupo controle.
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    Análises histoquímica e morfométrica de lesões endometrióticas induzidas em ratas e tratadas com dexametasona
    (Sociedade Brasileira de Patologia ClínicaSociedade Brasileira de PatologiaSociedade Brasileira de Citopatologia, 2009-04-01) Batista, Ana Paula Castor; Medeiros, Paloma Lys De; Teixeira, Álvaro Aguiar Coelho [UNIFESP]; Teixeira, Valéria Wanderley; Universidade Federal de Pernambuco; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
    INTRODUCTION: The literature reports that endometrial implants have receptors for steroid hormones primarily stimulated by estrogen and that some treatment strategies have been proposed in experimental models such as the use of synthetic glucocorticoids, for example, dexamethasone. OBJECTIVE: to analyze histochemically and morphometrically endometriotic lesions induced in rats and treated with dexamethasone (0.8 mg/kg/day). MATERIAL AND METHODS: Forty albino female rats (Wistar strain), with 90 days of age, weighing approximately 150 g, were induced with endometriosis and divided into groups: I - rats with endometriosis and evaluated after 34 days, II - rats with endometriosis and evaluated after 47 days, III - rats with endometriosis and 21 days post-surgery treated with dexamethasone for 13 days and IV - rats with endometriosis and 21 days post-surgery treated with dexamethasone for 13 days and euthanized after a period of 13 days starting from the end of treatment. The fragments of endometrial implants were fixed in Bouin, embedded in Paraplast and stained with hematoxylin-eosin and Mallory trichrome. The mean number of glands was compared through nonparametric Tukey-Kramer test (p < 0,05). RESULTS: Dexamethasone reduced inflammation in the endometrial implants, the collagen content in the stroma and decreased significantly the area occupied by glands (GI - 123.25 ± 6.44ª; IGI - 113 ± 6.27ª; GIII - 81.66 ± 3.05b and GIV - 94 ± 6.24b). CONCLUSION: The applied dexamethasone dosage reduces estrogenic effects in endometrial implants in rats.
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    Biocompatibilidade dos implantes de mama com superfície de espuma de silicone
    (Universidade Federal de São Paulo, 2021-07-14) Achilles, Rodrigo Bredariol [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; http://lattes.cnpq.br/9969803499258672; http://lattes.cnpq.br/6653322268021794; Universidade Federal de São Paulo (UNIFESP)
    Este estudo teve como objetivo estudar a biocompatibilidade do implante de mama com superfície de espuma de silicone, a partir da citotoxicidade, resposta inflamatória, colágeno produzido e compará-lo com outros dois tipos de implante disponíveis no mercado: nanotextura e microtextura. Para o teste de biocompatibilidade, foi empregado o teste de subcutâneo em roedores. Nesse estudo, foram utilizados 30 ratos machos (Rattus, norvegicus, albinos, Wistar) distribuídos em três grupos (10 animais por grupo), com 2 implantes em cada animal: o grupo 1 recebeu o implante com superfície de nanotextura, o grupo 2 com microtextura e o grupo 3 com espuma de silicone. Três animais de cada grupo foram sacrificados no 7º e 15º dias, e quatro animais sacrificados no 30º dia pós-implantação. Para o estudo in vitro, foram utilizados fibroblastos murinos L929 expostos às superfícies de espuma de silicone, micro- e macrotextura. Nessa avaliação, foram realizados os testes do MTT e Alamar Blue. No estudo in vitro, a espuma de silicone demonstrou potencial citotóxico em fibroblastos um pouco maior que as outras texturas nos primeiros dias pós-implantação, mas sem significância estatística no teste do Alamar Blue. Na avaliação microscópica, a nanotextura apresentou sinais de alta celularidade mesmo no 30º dia, a microtextura e a espuma de silicone apresentaram uma resolução da resposta inflamatória mais rápida, com amadurecimento precoce do tecido conjuntivo e diminuição da celularidade. A mesma resposta foi observada na coloração picro-sirius, com uma maturação mais rápida do colágeno no grupo da espuma de silicone. Desta forma, a espuma de silicone apresentou boa compatibilidade tantos nos ensaios in vitro como in vivo, mostrando-se uma boa opção de textura para implantes de mama.
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    CA1 inactivation impairs episodic-like memory in rats
    (Academic Press Inc Elsevier Science, 2017) Drieskens, Davi Carvalho; Neves, Livia Rodrigues; Pugliane, Karen Cristina; Montenegro Bento de Souza, Ingrid Brasilino; Lima, Alvaro da Costa [UNIFESP]; da Silva Stiebbe Salvadori, Mirian Graciela; Ribeiro, Alessandra Mussi [UNIFESP]; Silva, Regina Helena [UNIFESP]; Barbosa, Flavio Freitas
    Episodic memory was initially believed to be unique to humans. However, studies demonstrate that non-human species discriminate items based on the triad what, where and when. Here we addressed the role of the dorsal hippocampal subfield CA1 in an integrative what-where-when task in Wistar rats. We performed bilateral inactivation of dorsal CA1 with the GABAA agonist muscimol previously to the task. As expected, sham-operated animals recollected an integrative memory for objects (what), their places (where) and temporal order (when). However, the inactivation of CA1 impaired the performance of the three components of episodic-like memory. In addition, total time of objects exploration and distance traveled were not different between groups, indicating that rats had similar levels of motivation, thus, alterations in exploration does not account for impaired locomotor performance. Altogether, our data provides evidence that CA1 plays an important role in episodic-like memory. (C) 2017 Elsevier Inc. All rights
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    Determinação da ingestão alimentar e do gasto energético de ratos jovens submetidos à restrição crônica de sono
    (Universidade Federal de São Paulo (UNIFESP), 2017-12-02) Menezes, Leticia [UNIFESP]; Luz, Jacqueline [UNIFESP]; Suchecki, Deborah [UNIFESP]; http://lattes.cnpq.br/0735654567907174; http://lattes.cnpq.br/3430575558950797; http://lattes.cnpq.br/3167809516440639; Universidade Federal de São Paulo (UNIFESP)
    Sleep has been of interest to the scientific community for many years because it is a complex state that influences the functioning of the body as a whole. The use of animal models is very useful to understand the relation between insufficient sleep and the physiological, metabolic and behavioral changes. However, animal studies have raised a paradox: the concomitant presence of hyperphagia and the reduction of body weight gain. It is known that sleep restriction is a stressful factor that can induce stereotyped behavior in animals, leading to increased food spillage and not necessarily to increased food intake. It is also known that sleep deprivation / restriction can lead to increased energy expenditure. Purpose: determine the correction factor for energy intake of rats in chronic sleep restriction, considering the food spillage and evaluate the energy expenditure and body composition. Methods: male Wistar rats were divided into two groups: control (C) and restricted (R). Restricted groups were submitted to chronic sleep restriction by the single plataform method for 7, 14 and 21 days. Food intake and body weight were monitored daily. To determine the correction factor, spilled food was separated from the faeces daily. At the end of each experimental period, the animals were submitted to euthanasia to determine the energy balance and body composition. Student’s t-test was used for statistical analyses. Results: when the amount of spilled food was taken into account, restricted animals presented no significant difference in their energy intake compared to control ones. Restricted groups, despite the higher levels of metabolizable energy, presented lower fat content due to a higher energy expenditure and lower metabolic efficiency. Conclusion: it is necessary to use a correction factor for the adequate analysis of food intake of animals submitted to chronic sleep restricion, in order to avoid its overstimation due to the stereotyped behavior of gnawing. In fact, sleep restricted animals presented increased energy expenditure throughout the experimental period.
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    Efeito da associação entre obesidade neuroendócrina e exócrina experimental sobre a pressão arterial de cauda e o metabolismo de glicose de ratos Wistar
    (Sociedade Brasileira de Nefrologia, 2010-06-01) Pastore, Andréa Paula [UNIFESP]; Cesaretti, Mario Luis Ribeiro [UNIFESP]; Ginoza, Milton [UNIFESP]; Voltera, Aline Francisco [UNIFESP]; Kohlmann Junior, Osvaldo [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); PUC-SP
    OBJECTIVE: To study two different models of obesity, exocrine and endocrine, and its association on tail arterial pressure (TAP), body weight (BW), glucose metabolism and visceral fat content. METHODS: Male Wistar rats were studied. The MSG group was composed by rats that received of MSG in neonatal period. At the 3rd month of life, part of these animals received cafeteria diet. Animals received saline control in the neonatal period. In the 12 weeks of study, body weight and blood pressure were measured twice a week. In the end of this period on, Oral Glucose Tolerance Test (OGTT) was performed and the Insulin Sensitivity Index (ISI) was calculated, also the left Relative Ventricular Weight (RLW) and Relative Epididimal Fat Weight (REFW) were obtained. RESULTS: No changes on BW and TAP were verified. The obesity induced by MSG and CAF, individually, let to increases on insulin resistance (WST = 23,25 ± 9,31; CAF = 15,92 ± 9,10*; MSG = 13,41 ± 3,84* mg-1mU-1, p < 0,05 vs WST) and relative epididimal fat content (WST = 6,20 ± 0,57; CAF = 8,27 ± 1,53*; MSG = 8,23 ± 1,98* g/100 g, *p < 0,05) when these rats were compared to control rats. An enhanced effect upon these parameters was observed with the association of both obesity models (MSG+CAF = 9,34 ± 5,77 mg-1mU-1, p < 0,05 vs MSG and CAF) and visceral fat content (MSG+CAF = 11,12 ± 3,85 g/100g, p < 0,05 vs MSG and CAF). CONCLUSION: The association of these two experimental models of obesity aggravates insulin resistance that probably is due at least in part to the increase of visceral fat content.
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    Efeito do treinamento aeróbio na regulação hormonal e metabólica em ratos
    (Universidade Federal de São Paulo (UNIFESP), 2008-06-25) Costa, Carlos Alberto Nannini [UNIFESP]; Dâmaso, Ana Raimunda [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Objective: Observe metabolic behavior and physiological adjustments promoted by a protocol of physical activities in aquatic way with the use of additional loads varying between 3 and 5% of body weight. Methods: Thirty adult male Wistar rats were randomly divided into two groups: the Trained Group (TG) and Control Group (CG). The 15 animals of the TG, which underwent physical training, were subdivided into three subgroups: GT1, GT2 and GT3. They underwent 5 weekly swimming sessions during 60 minutes, respectively totaling 3, 6 and 12 weeks of training. Insulin concentration doses, IGF, glucose and lactate at different periods and stages of protocol were used as tools to interpret possible adaptations. ANOVA ONE-WAY for unpaired data was the statistical method for glucose, insulin and IGF analysis. ANOVA TWO-WAY, statistic SAS for PC 6.08 (SAS Institute, Cary, NC) was used for plasmatic lactate. Results: No significant changes in plasmatic concentrations occurred. Conclusion: Current analysis showed that experimental model used does not induce physiological adjustments and hormone adaptations when these are analyzed by the above-mentioned methods and biochemical variables. Other researches should be undertaken involving long-term experiments coupling distinct techniques and approaches.
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    Effects of brief and long maternal separations on the HPA axis activity and the performance of rats on context and tone fear conditioning
    (Elsevier B.V., 2007-12-03) Guijarro, Jussara Z.; Tiba, Paula A.; Ferreira, Tatiana L.; Kawakami, Suzi E.; Oliveira, Maria Gabriela M.; Suchecki, Deborah; Universidade Federal de São Paulo (UNIFESP)
    Previous studies show that early life events result in neurobehavioural alterations that may be either beneficial or detrimental to the stress response. Given the close relationship between corticosterone secretion and mnemonic processes, the purpose of the present study was to investigate the effects of brief (BMS, 15 min) and long maternal separations (LMS, 180 min) on memory tasks in adult rats, assessed by context and tone fear conditioning. At adulthood, males were evaluated for behavioural and hormonal reaction to the training environment, being tested for context fear conditioning; tone fear conditioning; and learning curve in the context fear conditioning, in which rats were daily re-exposed to the context, followed by a brief footshock and in the last day of the experiment (day 5) animals were exposed to the context. Corticosterone and ACTH plasma levels were determined in naive rats (basal) or 5, 25 or 45 min after each test. Peak ACTH and corticosterone levels were similar among the groups after context fear conditioning; however, levels of CTL rats remained elevated for a longer time. in the learning curve of context fear conditioning, both BMS and LMS rats exhibited less freezing behaviour than CTL rats, without differences in hormone secretion. There was neither an association between activity of the HPA axis and performance on memory tasks nor different activational properties of the tasks on the HPA axis between BMS and LMS rats, i.e., both manipulations lead to similar performance in hippocampus-dependent and independent memory tasks. (C) 2007 Elsevier B.V. All rights reserved.
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    Estudo comparativo da ação do fator de crescimento de fibroblastos e fragmentos de nervo na regeneração de nervo tibial em ratos
    (Sociedade Brasileira de Ortopedia e Traumatologia, 2007-01-01) Hirakawa, Celso Kiyoshi [UNIFESP]; Grecco, Marco Aurélio Sertório [UNIFESP]; Santos, João Baptista Gomes dos [UNIFESP]; Leite, Vilnei Matiolli [UNIFESP]; Faloppa, Flávio [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    OBJECTIVE: To quantitatively compare rats' tibial nerve regeneration stimulation by Fibroblast Growth Factor (FGF) and nerve fragments using silicone tubes. METHODS: 18 Wistar rats were employed in this experiment. The experimental surgery consisted of resection of an 8-mm tibial nerve segment, followed by an interposition of silicone tubes. On the right side, the tube was filled with a Fibroblast Growth Factor (FGF) solution, and on the left side, it was filled with 1 mm nerve segments. After three months, the animals were submitted to an additional surgery for exposing tibial nerves to the neuronal marker Fluoro-Gold®. After 48 hours, they were perfused with a paraformaldehyde solution and the medullar segment between L3 and S1 was removed and cut into 40 mum-thick segments. RESULTS AND CONCLUSION: The results of neuronal counts showed a higher amount of neurons on the side where FGF was used compared to the side where nervous fragments were placed, suggesting a superior performance of the fibroblast growth factor over nerve fragments for stimulating nervous regeneration in silicone tubes.
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    Estudo comparativo entre enxerto autógeno e enxerto muscular coberto com tubo de veia autógeno em nervos tibiais de ratos wistar, utilizando o fluoro-gold® como marcador neuronal
    (Sociedade Brasileira de Ortopedia e Traumatologia, 2007-01-01) Fernandes, Marcela [UNIFESP]; Valente, Sandra Gomes [UNIFESP]; Amado, Débora [UNIFESP]; Fernandes, Maria Jose da Silva [UNIFESP]; Naffah-Mazzacoratti, Maria da Graca [UNIFESP]; Santos, João Baptista Gomes dos [UNIFESP]; Faloppa, Flávio [UNIFESP]; Leite, Vilnei Mattioli [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The purpose of this work was to study nervous regeneration through neurons counts by comparing two surgical techniques for addressing nervous gaps on 15 rats' lower limbs. Initially, a 12-mm long vein tube from the left outer jugular was obtained, and then both lower limbs are operated, exposing the tibial nerve at each side and performing a resection of an 8-mm nerve segment, at the same time simulating a gap and an autogenous nerve graft. Left gap repair consisted of a usual conventional graft for nervous injury repair by means of microsurgical suture. The gap repair on right lower limbs was made through quadriceps muscle, treated with liquid nitrogen, covered with an 8-mm tube of jugular vein. After four months, the animals were submitted to a new surgery for exposing tibial nerves to the Fluoro-Gold® neuronal marker. After 48 hours, the rats were perfused and medullar segment between L3 and S1 was removed and subsequently cut into 40µm sections. Neurons on all sections were counted, and no statistical differences were found between both surgical techniques.
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    Estudo da ação da lovastatina no desenvolvimento do modelo experimental de epilepsia induzido pela pilocarpina em ratos
    (Universidade Federal de São Paulo (UNIFESP), 2011-06-29) Gouveia, Telma Luciana Furtado [UNIFESP]; Naffah-Mazzacoratti, Maria da Graca [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Introduction: Inflammation has been associated with several neurodegenerative diseases and experimental and clinical data suggest a crucial role in inflammatory processes in the development of epilepsy, particularly in seizure-generating mechanisms (ictogenesis) and transformation of a normal neuronal network into a network generating seizures. Lovastatin, a drug used in the reduction of cholesterol synthesis, is also related to the inflammatory response and can modulate cytokine production reducing the oxidative stress. Objectives: This study aimed to analyze the action of lovastatin in different stages of development model of epilepsy induced by pilocarpine in rats. Methods: Male Wistar rats were analyzed in three periods of the pilocarpine-induced epilepsy (350mg/kg) into phases: acute (24h), silent (15 days) and chronic (30 days after the 1st spontaneous seizure) and for each period of this model we used 4 groups of animals: saline-treated, lovastatin (Lova), pilocarpine (Pilo) and pilocarpine + lovastatin (Pilo+ Lova). Treatment with lovastatin (20 mg / kg) begun 2 h after the onset of status epilepticus (SE) and was administered for 15 days, twice a day the animals in the silent and chronic phases. The brain was processed for performing real-time PCR and immunohistochemistry of IL-1ƒÀ, IL-6, TNF-ƒ¿, IL-10 and kinin B1 and B2 receptors and quantification of amino acids in the hippocampus. Besides, the hippocampal tissue was processed for Nissl techniques and Neo-Timm. In addition, body temperature was measured in the acute phase and the duration of the silent period and seizure frequency in chronic phase was analyzed. Results: Treatment with lovastatin in Pilo + Lova group showed decreased expression of mRNA and proteins IL-1ƒÀ and TNF-ƒ¿ in the three phases of this model, We also noted reduction of kinin B1 and B2 receptor in the acute and IL-6 into acute and silent periods. There was an increased expression of IL-10 in the chronic phase of this model. There was no change in amino acids levels in the hippocampus of rats from Pilo+Lova group when compared to Pilo group. We observed a normalization of body temperature of rats subjected to SE and treated with lovastatin. There was no significant difference between the group Pilo and Pilo + Lova on the duration of the silent phase and in seizure frequency. We observed a preservation of neurons in CA1 and also a reduction of mossy fiber sprouting in Pilo+ Lova group as compared to the Pilo group in the chronic phase of the model. Conclusion: This study demonstrated that treatment with lovastatin decreased number of important parameters related to the neuronal damage induced by SE in the hippocampus of rats at different stages of the experimental model of epilepsy induced by pilocarpine.
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    Estudo da regeneração de nervos tibiais de ratos Wistar em sutura primária com gap e sem gap, cobertos por segmentos de veia
    (Sociedade Brasileira de Ortopedia e Traumatologia, 2012-01-01) Santos, Ewerton Bastos Dos [UNIFESP]; Fernandes, Marcela [UNIFESP]; Santos, João Baptista Gomes dos [UNIFESP]; Leite, Vilnei Mattioli [UNIFESP]; Valente, Sandra Gomes [UNIFESP]; Faloppa, Flávio [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    OBJECTIVE: This study compared nerve regeneration in Wistar rats, using epineural neurorrhaphy with a gap of 1.0 mm and without a gap, both wrapped with jugular vein tubes. Motor neurons in the spinal cord between L3 and S1 were used for the count, marked by exposure of the tibial nerve to Fluoro-Gold (FG). METHOD: The tibial nerves on both sides were cut and sutured, with a gap on one side and no gap in the other. The sutures were wrapped with a jugular vein. Four months after surgery the tibial nerves were exposed to Fluoro-Gold and the motor neuron count performed in the spinal cord. RESULTS: The results were statistically analyzed by the paired Wilcoxon test. There was a statistical difference between the groups with and without gap in relation to the motor neuron count (p=0.013). CONCLUSION: The epineural neurorraphy without gap wrapped with jugular vein showed better results for nerve regeneration than the same procedure with gap. Level of Evidence: Experimental Study.
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    Estudo da regeneração esplênica autóloga e heterotópica em ratos
    (Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2005-06-01) Souza, José Carlos Lacerda De; Athiê, Emilio; Marigo, Carlos; Rahal, Fares; Fagundes, Djalma José [UNIFESP]; Santa Casa de São Paulo Faculdade de Medicina; Universidade Estadual de Londrina; Universidade Federal de São Paulo (UNIFESP)
    PURPOSE: verify the cytological and histological aspects of the regeneration of fragments of autologous and heterotopic spleen implanted in peritoneal cavity and subcutaneous screen in Wistar albino rats. METHODS: forty four Wistar rats were assigned to one of two groups A(n=22) and B(n=22), which received their implants in subcutaneous screen and peritoneal cavity, respectively, under anesthesia. Those groups were redistributed in two other subgroups A1 (n=11) and B1(n=11), which received one and four splenic fragments in the areas of study. The remaining spleen was guided for cytological and histological processing, and was used as a control group. After five weeks, they were submitted to euthanasia, and peritoneal cavity opening took place as well as subcutaneous screen was taken off in order to search for regenerated splenic tissue. Cytological and histological assessment in the regenerated splenic tissue was performed, and the results were compared to the control group. Statistical analysis no parametric tests (p=>0,05) were used for. RESULTS: there were no statistically significant differences in relation to regenerated splenic tissue in subcutaneous screen (n=22) and the peritoneal cavity (n=22). In relation between presence and absence of regeneration, they're no statistically significant differences (p=0,182). Cytological and histological assessment did not show any statistically significant difference in relation to the control group. CONCLUSION: regeneration of autologous and heterotopic splenic tissue in mice is viable, and occurs frequently. Cytological and histological aspects are similar to normal spleen.
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    Estudo morfológico de aderências peritoneais induzidas pela rifamicina, em ratos
    (Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2001-06-01) D´oliveira, Djalma Manoel Rodrigues [UNIFESP]; Nigro, Amaury José Teixeira [UNIFESP]; Fagundes, Djalma José [UNIFESP]; Novo, Neil Ferreira [UNIFESP]; Juliano, Yara [UNIFESP]; Pimenta, Ana Luisa Pinheiro; Universidade Federal de São Paulo (UNIFESP); Prefeitura do Rio de Janeiro Instituto Municipal de Medicina Veterinária JORGE VAITSMAN Serviço de Patologia Animal
    The intraperitoneal use of rifamycin s.v. and its influence in postoperative peritoneal adhesions occurrence was analysed in a ninety male rats experimental study. The control group was formed by 45 animals subjected to laparotomy and instillation of 2mL of saline solution with rhythmic digital movements in the four quadrants of the peritoneal cavity for 2 minutes. After this procedure, the remaining saline solution was aspirated with a syringe, followed by immediate laparorrhaphy. The experiment group (n=45) was submitted to a similar procedure with instillation of a solution of rifamycin s.v. 500mg diluted in 500mL of a saline vehicle, according to the same movement used in the control group. The animals of both control and experiment groups were distributed in three subgroups with equal number (n=15), according to the euthanasia period, which was 7, 14 and 21 days postoperative. Peritoneal adhesions were quantified in the euthanasia periods, using a method described by MORENO-EGEA, AGUAYO, ZAMBUDIO and PARRILLA (1993). The experiment group presented a rate of adhesion significantly high as compared to the control group in all subgroups. This difference was higher in animals with an euthanasia period of 21 days.
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    Os exercícios aeróbio e resistido melhoram a memória espacial de ratos por mecanismos diferentes
    (Universidade Federal de São Paulo (UNIFESP), 2011-03-30) Cassilhas, Ricardo Cardoso [UNIFESP]; Mello, Marco Tulio de [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    A growing body of scientific evidence indicates that exercise has a positive impact on human health and on neurological health in particular. Effects such as increased BDNF and IGF-1 neurotrophic activity are induced by aerobic exercise and appear to influence hippocampal neurons, leading to improved spatial learning and memory. However, nothing is known about the effect of resistance exercise on hippocampus-dependent memory or whether the cellular pathways associated with aerobic exercise are also activated by resistance training. Objective: we therefore tested whether spatial learning and memory in rats is similarly enhanced by aerobic or resistance exercise and whether the cellular signals involved are similar, focusing on the BDNF/ TrKB and IGF-1/ IGF-1R pathways. Material and Methods: Adult male Wistar rats underwent eight weeks of aerobic training on a treadmill (AERO group) or resistance training on a vertical ladder (RES group); control and sham groups were also included. After the training period, both the AERO and RES groups showed improved learning and spatial memory. In addition, the BDNF/TrkB/CaMKII pathway had a higher activity in the AERO group than in the RES group. In contrast, the RES group showed greater activation of the IGF-1/IGF-1R/AKT pathway. Moreover, the two exercise groups had similar increases in synapsin and synaptophysin expression. Conclusions: We therefore conclude that, in rats, both aerobic and resistance training for eight weeks increases learning and spatial memory in a similar manner. However, the two forms of exercise seem to employ at least partially divergent mechanisms. Specifically, aerobic exercise modulates neuroplasticity selectively via the BDNF/TrkB pathway by activating CaMKII and stimulating the synthesis of synapsin and synaptophysin. In contrast, resistance training appears to increase synapsin and synaptophysin expression via the IGF-1/IGF-1R pathway.
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    Experimental chronic low-frequency resistance training produces skeletal muscle hypertrophy in the absence of muscle damage and metabolic stress markers
    (Wiley-Blackwell, 2010-04-01) Zanchi, Nelo Eidy; Lira, Fabio Santos [UNIFESP]; Seelaender, Marilia; Lancha-, Antonio Herbert; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)
    Volitional animal resistance training constitutes an important approach to modeling human resistance training. However, the lack of standardization protocol poses a frequent impediment to the production of skeletal muscle hypertrophy and the study of related physiological variables (i.e., cellular damage/inflammation or metabolic stress). Therefore, the purposes of the present study were: (1) to test whether a long-term and low frequency experimental resistance training program is capable of producing absolute increases in muscle mass; (2) to examine whether cellular damage/inflammation or metabolic stress is involved in the process of hypertrophy. in order to test this hypothesis, animals were assigned to a sedentary control (C, n = 8) or a resistance trained group (RT, n = 7). Trained rats performed 2 exercise sessions per week (16 repetitions per day) during 12 weeks. Our results demonstrated that the resistance training strategy employed was capable of producing absolute mass gain in both soleus and plantaris muscles (12%, p<0.05). Furthermore, muscle tumor necrosis factor (TNF-alpha) protein expression (soleus muscle) was reduced by 24% (p<0.01) in trained group when compared to sedentary one. Finally, serum creatine kinase (CK) activity and serum lactate concentrations were not affected in either group. Such information may have practical applications if reproduced in situations where skeletal muscle hypertrophy is desired but high mechanical stimuli of skeletal muscle and inflammation are not. Copyright (C) 2010 John Wiley & Sons, Ltd.
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    Experimental endometriosis reduction in rats treated with Uncaria tomentosa (cat's claw) extract
    (Elsevier B.V., 2011-02-01) Nogueira Neto, Joao [UNIFESP]; Coelho, Tarcisio Mota; Aguiar, Guilherme Carneiro; Carvalho, Laura Rosa; Portela de Araujo, Ana Giselia; Girao, Manuel Joao B. C. [UNIFESP]; Schor, Eduardo [UNIFESP]; Univ Fed Maranhao; Universidade Federal de São Paulo (UNIFESP)
    Objective: the aim of this study was to analyze the macroscopic and histological changes that occur in experimental endometriosis after treatment with Uncaria tomentosa.Study design: Experimental endometriosis was induced in twenty-five female Wistar rats. After three weeks, 24 animals developed grade III experimental endometriosis and were divided into two groups. Group U received U. tomentosa extract orally (32 mg/day), and group C (control group) received a 0.9% sodium chloride solution orally (1 ml/100 g of body weight/day). Both groups were treated with gavage for 14 days. At the surgical intervention and after the animal was euthanized, the implant volume was calculated with the following formula: [4 pi (length/2) x (width/2) x (height/2)/3]. the auto-transplants were removed, dyed with hematoxylin-eosin, and analyzed by light microscopy. the Mann-Whitney test was used for the independent samples, and the Wilcoxon test analyzed the related samples, with a significance level of 5%.Results: the difference between the initial average volumes of the autotransplants was not significant between the groups (p = 0.18). However, the final average volumes were significantly different between the groups (p = 0.001). There was a significant increase (p = 0.01) between the initial and final average volumes in the control group, and treatment with the U. tomentosa caused a marked reduction in the growth over time (p = 0.009). Histologically, in the experimental group (n = 10) six rats had a well-preserved epithelial layer, three had mildly preserved epithelium, and one had poorly preserved epithelium. the epithelial layer occasionally presented sporadic epithelial cells. the control group (n = 12) presented seven cases (58.3%) of well-preserved epithelial cells and five cases (41.7%) of mildly preserved epithelial cells.Conclusions: Cat's claw extract appears to be a promising alternative for treating endometriosis. (c) 2010 Elsevier Ireland Ltd. All rights reserved.
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    Fos induction and persistence, neurodegeneration, and interneuron activation in the hippocampus of epilepsy-resistant versus epilepsy-prone rats after pilocarpine-induced seizures
    (Wiley-Blackwell, 2004-01-01) Fabene, P. F.; Andrioli, A.; Priel, M. R.; Cavalheiro, E. A.; Bentivoglio, M.; Univ Verona; Universidade Federal de São Paulo (UNIFESP)
    Previous studies demonstrated that the spiny rat Proechimys guyannensis exhibits resistance to experimental epilepsy. Neural activation was studied in the Proechimys hippocampus, using Fos induction, within 24 h after pilocarpine-induced seizures; neurodegenerative events were investigated in parallel, using FluoroJade B histochemistry. These parameters were selected since pilocarpine-induced limbic epilepsy is known to elicit immediate early gene expression and cell loss in the hippocampus of seizure-prone laboratory rodents. At variance with matched experiments in Wistar rats, pilocarpine injection resulted in Proechimys in seizure episodes that, as previously reported, did not develop into status epilepticus. At 3 h and 8 h after seizure onset, Fos immunoreactivity filled the dentate gyrus of both rat species, and was quite marked in pyramidal cells of the Proechimys Ammon's horn. At 24 h, Fos immunoreactivity dropped in the Wistar hippocampus and persisted in Proechimys. At 8 h and 24 h, FluoroJade-stained neurons were very few in the Proechimys hippocampus, whereas they were abundant in that of Wistar rats. Double immunohistochemistry for Fos and parvalbumin, the protein expressed by fast-spiking hippocampal interneurons, indicated that Fos was induced up to 24 h in the vast majority of parvalbumin-containing cells of the Proechimys hippocampus, and in a minority of these cells in the Wistar hippocampus. the findings demonstrate that early postepileptic neurodegeneration is very limited in the Proechimys hippocampus, in which sustained Fos induction persists for several hours. the findings also indicate that Fos induction and persistence may not correlate with seizure intensity and may not be associated with neuronal death. Finally, the data implicate differential mechanisms of interneuron activity in anti-convulsant and pro-convulsant phenomena. (C) 2004 Wiley-Liss, Inc.
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    Functional specializations within the tectum defense systems of the rat
    (Elsevier B.V., 2005-01-01) Schenberg, L. C.; Povoa, RMF; Costa, ALP; Caldellas, A. V.; Tufik, S.; Bittencourt, A. S.; Univ Fed Espirito Santo; Universidade Federal de São Paulo (UNIFESP)
    Here we review the differential contribution of the periaqueductal gray matter (PAG) and superior colliculus (SC) to the generation of rat defensive behaviors. the results of studies involving sine-wave and rectangular pulse electrical stimulation and chemical (NMDA) stimulation are summarized. Stimulation of SC and PAG produced freezing and flight behaviors along with exophthalmus (fully opened bulged eyes), micturition and defecation. the columnar organization of the PAG was evident in the results obtained. Defecation was elicited primarily by lateral PAG stimulation, while the remaining defensive behaviors were similarly elicited by lateral and dorsolateral PAG stimulation, although with the lowest thresholds in the dorsolateral column. Conversely, the ventrolateral PAG did not appear to participate in unconditioned defensive behaviors, which were only elicited by high intensity stimulation likely to encroach on adjacent regions. in the SC, the most important differences relative to the PAG were the lack of stimulation -evoked jumping in both intermediate and deep layers, and of NMDA-evoked galloping in intermediate layers. Therefore, we conclude that the SC may be only involved in the increased attentiveness (exophthalmus, immobility) and restlessness (trotting) of prey species exposed to the cues of a nearby predator. These responses may be distinct from the full-blown flight reaction that is mediated by the dorsolateral and lateral PAG. However, other evidences suggest the possible influences of stimulation schedule, environment dimensions and rat strain in determining outcomes. Overall our results suggest a dynamically organized representation of defensive behaviors in the midbrain tectum. (c) 2005 Elsevier B.V. All rights reserved.
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    Restrição alimentar intra-uterina e suas repercussões sobre o desenvolvimento da termorregulação da prole
    (Universidade Federal de São Paulo (UNIFESP), 2009-04-29) Souza, Thais Ladeira Vieira de [UNIFESP]; Luz, Jacqueline [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Background: Previous study from our laboratory has shown that intrauterine food restriction (IUFR) delayed thermoregulation of the newborns. In neonates brown adipose tissue (BAT) is essential for thermogenesis mainly due to the presence of uncoupling proteins (UCPs) and their expression can be modified by action of hormones such as thyroid hormone, leptin and insulin, which can be affected by food restriction. The sarcoplasmic reticulum Ca++ ATPase, (SERCA1) recently identified in BAT may contribute to heat production. Aim: The aim of this study was to evaluate the protein expression of UCP1, UCP2, UCP3 and SERCA1 in BAT and UCP3 and SERCA1 in skeletal muscle (SM) and the plasmatic concentration of insulin, leptin, T3 and T4 of newborn rats exposed to IUFR. Methods: Female Wistar EPM-1 control rats received chow ad libitum during pregnancy period (C) and food-restricted rats (R) received 50% of the amount ingested by C. Fifteen hours after birth, newborns were weighted and sacrificed by decapitation. Blood was collected for determination of insulin, leptin, T3 and T4 by ELISA. BAT and SM were used for determination of protein expression (UCPs and SERCA1) by immunohistochemistry. Unpaired Student’s t-test was used for statistical analysis of the results (p<0,05). Results: R animals (n=16) showed a significant lower weight gain (g) during pregnancy when compared to C (n=16) (27,6 ± 3,8 and 109,0 ± 4,1). R pups (n=172) showed a significant reduction in their body weight (g) at birth when compared to C (n=169) (4,82 ± 0,05 and 5,83 ± 0,04); however, there was no reduction in number of pups per litter. IUFR caused a significant increase in the expression (pixels) of UCP1 and UCP2 in BAT of the pups (42% and 53% respectively). UCP3 and SERCA1 expression in BAT and SM showed no significant differences between groups. Plasmatic insulin (ng/ml) was significantly higher in R pups (n=8) when compared to C (n=13) (3,34 ± 0,78 and 1,17 ± 0,18) and T3 levels (ng/ml) was significantly lower in R pups (n=10) when compared to C (n=14) (0,82 ± 0,06 and 1,09 ± 0,08). No differences between groups were found for leptin (pg/ml) (R (n=8) 987,79 ± 261,08 and C (n=11) 1255,54 ± 392,37) and T4 (ng/ml) levels (R (n=10) 20,99 ± 3,74 and C (n=12) 16,00 ± 1,68). Conclusion: The delay in development of thermoregulation previously described in these animals appears not to result from impairment in thermogenesis, but from an increase in heat loss, since IUFR caused low birth weight in pups, leading to greater surface/ volume ratio. The higher expression of UCP1 and UCP2 in BAT showed by R pups possibly occurred as a compensatory mechanism to increase thermogenesis, which may have been modulated by hormonal regulation.