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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.
1

Angiotensin II Type 1 Receptor Activation in the Subfornical Organ Mediates Sodium-induced Pressor Responses In Wistar Rats

Tiruneh, Missale 27 July 2012 (has links)
Na+ sensitive hypertension in Dahl salt sensitive rats (Dahl S) or spontaneously hypertensive rats (SHR) is linked to intrinsic changes in the brain that favour increased Na+ entry into the cerebrospinal fluid (CSF) followed by increases in sympathetic hyperactivity and hypertension (Huang et al 2004). Similar responses are observed in salt resistant and Wistar rats that receive an intracerebroventricular (icv) infusion of Na+ rich artificial cerebrospinal fluid (aCSF) (Huang et al 2001, 2006). Downstream to increased CSF[Na+], a pathway has been described involving mineralocorticoid receptors (MRs), benzamil sensitive Na+ channels, “ouabain”, and angiotensin II type 1 receptors (AT1-R) (Huang et al 1998, Zhao et al 2001, Wang and Leenen 2003, Huang et al 2008). Blood pressure (BP) responses to increased CSF[Na+] may involve activation of AT1-R in the subfornical organ (SFO) as the BP response to injection of NaCl into a lateral ventricle can be blocked by AT1-R blockade in the SFO (Rohmeiss et al 1995a). The role of aldosterone and AT1-R in the SFO was investigated in mediating the BP and heart rate (HR) response to increases in CSF[Na+] and local [Na+]. Results show that infusion of 0.45M and 0.6M Na+ rich aCSF into the SFO increases BP but not HR. The BP is unchanged by infusion of a mannitol solution osmotically equivalent to 0.6M Na+ rich aCSF indicating that the SFO is Na+ sensitive. The BP response to a lower concentration of Na+ (0.45M) is enhanced by prior infusion of aldosterone while BP response to 0.6M is not further enhanced suggesting that the SFO may have maximal responsiveness to acute increases in [Na+] at 0.6M. The BP responses to Na+ rich aCSF in the SFO and the enhancement of those responses by aldosterone can be blocked by infusion of the AT1-R blocker Candesartan in the SFO. This response appears therefore to be mediated in the SFO through AT1-R activation, likely through Ang II release in the SFO. ICV infusion of Na+ rich aCSF increases BP but not HR and this response is partially blocked by infusion of the AT1-R blocker Candesartan in the SFO. This indicates that nearly half the BP responses to icv infusion of Na+ rich aCSF is mediated through AT1-R activation in the SFO. Lastly, contrary to icv, PVN and MnPO studies (Huang and Leenen 1996, Budzikowski and Leenen 2001, Gabor and Leenen 2009) ouabain in the SFO does not increase BP or HR. In conclusion, these results show that the SFO is Na+ sensitive and mediates half the BP responses to changes in CSF[Na+] through a mechanism that involves AT1-R activation. The SFO is further sensitized to Na+ by aldosterone presumably through its genomic effects. Lastly, ouabain in the SFO does not increase BP or HR suggesting that endogenous ouabain in the SFO is not involved in modulating BP or HR responses.
2

Angiotensin II Type 1 Receptor Activation in the Subfornical Organ Mediates Sodium-induced Pressor Responses In Wistar Rats

Tiruneh, Missale 27 July 2012 (has links)
Na+ sensitive hypertension in Dahl salt sensitive rats (Dahl S) or spontaneously hypertensive rats (SHR) is linked to intrinsic changes in the brain that favour increased Na+ entry into the cerebrospinal fluid (CSF) followed by increases in sympathetic hyperactivity and hypertension (Huang et al 2004). Similar responses are observed in salt resistant and Wistar rats that receive an intracerebroventricular (icv) infusion of Na+ rich artificial cerebrospinal fluid (aCSF) (Huang et al 2001, 2006). Downstream to increased CSF[Na+], a pathway has been described involving mineralocorticoid receptors (MRs), benzamil sensitive Na+ channels, “ouabain”, and angiotensin II type 1 receptors (AT1-R) (Huang et al 1998, Zhao et al 2001, Wang and Leenen 2003, Huang et al 2008). Blood pressure (BP) responses to increased CSF[Na+] may involve activation of AT1-R in the subfornical organ (SFO) as the BP response to injection of NaCl into a lateral ventricle can be blocked by AT1-R blockade in the SFO (Rohmeiss et al 1995a). The role of aldosterone and AT1-R in the SFO was investigated in mediating the BP and heart rate (HR) response to increases in CSF[Na+] and local [Na+]. Results show that infusion of 0.45M and 0.6M Na+ rich aCSF into the SFO increases BP but not HR. The BP is unchanged by infusion of a mannitol solution osmotically equivalent to 0.6M Na+ rich aCSF indicating that the SFO is Na+ sensitive. The BP response to a lower concentration of Na+ (0.45M) is enhanced by prior infusion of aldosterone while BP response to 0.6M is not further enhanced suggesting that the SFO may have maximal responsiveness to acute increases in [Na+] at 0.6M. The BP responses to Na+ rich aCSF in the SFO and the enhancement of those responses by aldosterone can be blocked by infusion of the AT1-R blocker Candesartan in the SFO. This response appears therefore to be mediated in the SFO through AT1-R activation, likely through Ang II release in the SFO. ICV infusion of Na+ rich aCSF increases BP but not HR and this response is partially blocked by infusion of the AT1-R blocker Candesartan in the SFO. This indicates that nearly half the BP responses to icv infusion of Na+ rich aCSF is mediated through AT1-R activation in the SFO. Lastly, contrary to icv, PVN and MnPO studies (Huang and Leenen 1996, Budzikowski and Leenen 2001, Gabor and Leenen 2009) ouabain in the SFO does not increase BP or HR. In conclusion, these results show that the SFO is Na+ sensitive and mediates half the BP responses to changes in CSF[Na+] through a mechanism that involves AT1-R activation. The SFO is further sensitized to Na+ by aldosterone presumably through its genomic effects. Lastly, ouabain in the SFO does not increase BP or HR suggesting that endogenous ouabain in the SFO is not involved in modulating BP or HR responses.
3

Avaliações hematológicas e bioquímicas do uso de diclofenaco de sódio, meloxicam e firocoxibe em ratos wistar

Barbosa, Cristiane Moraes [UNESP] 28 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-28Bitstream added on 2014-06-13T18:51:23Z : No. of bitstreams: 1 barbosa_cm_me_botfmvz_prot.pdf: 839586 bytes, checksum: 13cf1cd16f269b63e432c194dd643d2d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação para o Desenvolvimento da UNESP (FUNDUNESP) / O presente trabalho avaliou os parâmetros hematológicos e bioquímicos do uso de diclofenaco de sódio, meloxicam e firocoxibe em ratos Wistar. Os ratos foram distribuídos em grupos: G1 (controle), G2 (diclofenaco de sódio: 15 mg/kg), G3 (meloxicam: 2,0 mg/ kg), G4 (meloxicam: 10,0 mg/ kg), G5 (firocoxibe: 5,0 mg/ kg) e G6 (firocoxibe: 25,0 mg/ kg). Os fármacos foram administrados por via intragástrica (gavage) a cada 24 horas, durante 5 dias e avaliados em 3 momentos: M1 (48 horas após o início do tratamento), M2 (96 horas após o início do tratamento) e M3 (72 horas após o término do tratamento). Em cada momento de cada grupo, foram avaliados de 5 a 7 animais e realizados os exames laboratoriais. Não foram observadas alterações significativas nos parâmetros bioquímicos e hematológicos com o uso de meloxicam e firocoxibe. O diclofenaco de sódio produziu alterações no eritrograma (redução do hematócrito e na taxa de hemoglobina) durante o tratamento e não alterou a contagem das plaquetas e leucometria, com exceção dos basófilos. Não produziu alterações nas atividades de AST, FA, GGT, uréia, creatinina e potássio. Entretanto, causou diminuições temporárias da albumina e globulina e elevações nos valores séricos de sódio. Conclui-se que o diclofenaco de sódio não produz grandes alterações no hemograma e exames bioquímicos, mas deve ser usado com cautela em roedores. O meloxicam e firocoxibe não produzem alterações e efeitos deletérios dose-dependentes no hemograma e parâmetros bioquímicos, portanto são drogas seguras em ratos. / This work has evaluated the hematological and biochemical profile by the use of sodium diclofenac, meloxicam and firocoxib in Wistar rats. The rats were distributed in groups: G1 (control), G2 (diclofenac sodium: 15 mg/kg), G3 (meloxicam: 2,0 mg/ kg), G4 (meloxicam: 10,0 mg/ kg), G5 (firocoxib: 5,0 mg/ kg) e G6 (firocoxib: 25,0 mg/ kg). The drugs were administered intragastrically (gavage) once a day, during 5 days and evaluated in 3 moments: M1 (48 hours after the beginning of the treatment), M2 (96 hours after the beginning of the treatment) and M3 (72 hours after the ending of treatment). In each moment of each group, 5 to 7 animals were evaluated and laboratory exams were performed. There were no significant changes observed in the biochemical and hematological parameters by the use of meloxicam and firocoxib. One of effects of the sodium diclofenac was eritrogram variation as hematocrit and hemoglobin decrease during the treatment. In addition, the platelets and leukogram counts did not change except for basophil. There was no changes in AST, ALP, GGT, urea, creatinine and potassium values. However, the values of globulim and albumim decreased temporarily and the serum values of sodium incresead. It can concluded that diclofenac sodium does not provide large variations in the hemogram and biochemical profile, but it must be used with care in rodents. The meloxicam and firocoxib does not provide delletery effects in the hemogram and biochemical profile, thus these drugs can be considered safe in rats.
4

Caracterização das alterações laboratoriais e histopatológicas associadas à obstrução uretral experimentalmente induzida em ratos

Costa, Hugo Leonardo Riani [UNESP] 11 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-11Bitstream added on 2014-06-13T19:51:02Z : No. of bitstreams: 1 costa_hlr_me_botfmvz.pdf: 1355195 bytes, checksum: 2992cd80d156a33c682f6ce67ff9724e (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A obstrução uretral é uma emergência clínica freqüente no atendimento de pequenos animais. Com a evolução do quadro, ocorre parada na filtração glomerular e, consequentemente, desenvolvem-se várias alterações nos equilíbrios hídrico, eletrolítico e ácido-básico, além do acúmulo de metabólitos nitrogenados e toxinas orgânicas. Podem ocorrer modificações histopatológicas nos rins e na bexiga. Objetivou-se, neste estudo, caracterizar prospectivamente as alterações laboratoriais e histopatológicas de ratos apresentando obstrução uretral. Para tanto, foram utilizados 21 ratos Wistar com obstrução uretral induzida. Foram realizados os seguintes exames: hemogasometria venosa e determinação dos níveis de uréia, creatinina, sódio, potássio, cloreto, cálcio e fósforo. As avaliações foram repetidas a cada 8 horas durante 24 horas. Após esse período os animais foram eutanasiados e as bexigas e os rins enviados para exame histopatológico. Entre os exames bioquímicos, foram observadas elevações estatisticamente significativas nos níveis de uréia, creatinina, fósforo, magnésio e potássio, e diminuição nos níveis de cloreto. Com relação à hemogasometria, houve diferença estatisticamente significativa entre os valores de pH, PO2, PCO2, excesso de base, saturação de oxigênio e lactato. O exame histopatológico renal revelou a presença de alterações tubulares e glomerulares, enquanto a análise histopatológica das bexigas demonstrou a presença de hemorragia, separação de fibras musculares e infiltrado inflamatório. Conclui-se que a obstrução uretral provoca alterações que podem ser detectadas nos exames laboratoriais, sendo as mesmas agravadas no decorrer do tempo. Além disso, a persistência durante 24 horas é capaz de levar a alterações morfológicas no trato urinário. / Urethral obstruction is a frequent emergency in Veterinary clinics. The persistent urethral obstruction leads to blockage of renal filtration, resulting in several alterations in fluid, electrolyte and acid-base balance, besides the accumulation of nitrogenous metabolic products and organic toxins. Histopathological changes may occur in the kidneys and urinary bladder. Thus, this study aimed to prospectively characterize renal and vesical histopathological alterations in rats due to urethral obstruction. Twenty-one male Wistar rats (Rattus norvegicus) with experimental urethral obstruction were included in the study. Venous gasometry and determination of urea, creatinine, sodium, potassium, chloride, calcium and phosporus were performed. The avaliations were repeted each 8 hours during 24 hours. After that period, the animals were euthanatized for the collection of kidneys and bladder fragments to the histopathological exam. Biochemistry exams demonstrated statiscally significant elevations for the levels of urea, creatinine, phosporus, magnesium and potassium, and a decrease for the levels of chloride. Results of gasometry also demonstrated statiscally significant changes for pH, PO2, PCO2, base excess, oxygen saturation and lactate values. Histopathology analysis revealed kidney alterations in tubular and glomerular elements. The most important alterations found in urinary bladders were transmural hemorrhage, separation of muscle fibers and neutrophilic inflammatory infiltrate. Complete urethral obstruction induces important changes that can be detected by laboratorial exams, and the alterations worsen with the course of time. Besides that, the persistent obstruction during 24 hours is able to cause morphological changes in the kidneys and urinary bladder, which can be detected using histopathological exam.
5

Avaliações hematológicas e bioquímicas do uso de diclofenaco de sódio, meloxicam e firocoxibe em ratos wistar /

Barbosa, Cristiane Moraes. January 2008 (has links)
Orientador: Michiko Sakate / Banca: Regina Kiomi Takahira / Banca: Mário Roberto Hatayde / Resumo: O presente trabalho avaliou os parâmetros hematológicos e bioquímicos do uso de diclofenaco de sódio, meloxicam e firocoxibe em ratos Wistar. Os ratos foram distribuídos em grupos: G1 (controle), G2 (diclofenaco de sódio: 15 mg/kg), G3 (meloxicam: 2,0 mg/ kg), G4 (meloxicam: 10,0 mg/ kg), G5 (firocoxibe: 5,0 mg/ kg) e G6 (firocoxibe: 25,0 mg/ kg). Os fármacos foram administrados por via intragástrica (gavage) a cada 24 horas, durante 5 dias e avaliados em 3 momentos: M1 (48 horas após o início do tratamento), M2 (96 horas após o início do tratamento) e M3 (72 horas após o término do tratamento). Em cada momento de cada grupo, foram avaliados de 5 a 7 animais e realizados os exames laboratoriais. Não foram observadas alterações significativas nos parâmetros bioquímicos e hematológicos com o uso de meloxicam e firocoxibe. O diclofenaco de sódio produziu alterações no eritrograma (redução do hematócrito e na taxa de hemoglobina) durante o tratamento e não alterou a contagem das plaquetas e leucometria, com exceção dos basófilos. Não produziu alterações nas atividades de AST, FA, GGT, uréia, creatinina e potássio. Entretanto, causou diminuições temporárias da albumina e globulina e elevações nos valores séricos de sódio. Conclui-se que o diclofenaco de sódio não produz grandes alterações no hemograma e exames bioquímicos, mas deve ser usado com cautela em roedores. O meloxicam e firocoxibe não produzem alterações e efeitos deletérios dose-dependentes no hemograma e parâmetros bioquímicos, portanto são drogas seguras em ratos. / Abstract: This work has evaluated the hematological and biochemical profile by the use of sodium diclofenac, meloxicam and firocoxib in Wistar rats. The rats were distributed in groups: G1 (control), G2 (diclofenac sodium: 15 mg/kg), G3 (meloxicam: 2,0 mg/ kg), G4 (meloxicam: 10,0 mg/ kg), G5 (firocoxib: 5,0 mg/ kg) e G6 (firocoxib: 25,0 mg/ kg). The drugs were administered intragastrically (gavage) once a day, during 5 days and evaluated in 3 moments: M1 (48 hours after the beginning of the treatment), M2 (96 hours after the beginning of the treatment) and M3 (72 hours after the ending of treatment). In each moment of each group, 5 to 7 animals were evaluated and laboratory exams were performed. There were no significant changes observed in the biochemical and hematological parameters by the use of meloxicam and firocoxib. One of effects of the sodium diclofenac was eritrogram variation as hematocrit and hemoglobin decrease during the treatment. In addition, the platelets and leukogram counts did not change except for basophil. There was no changes in AST, ALP, GGT, urea, creatinine and potassium values. However, the values of globulim and albumim decreased temporarily and the serum values of sodium incresead. It can concluded that diclofenac sodium does not provide large variations in the hemogram and biochemical profile, but it must be used with care in rodents. The meloxicam and firocoxib does not provide delletery effects in the hemogram and biochemical profile, thus these drugs can be considered safe in rats. / Mestre
6

Angiotensin II Type 1 Receptor Activation in the Subfornical Organ Mediates Sodium-induced Pressor Responses In Wistar Rats

Tiruneh, Missale January 2012 (has links)
Na+ sensitive hypertension in Dahl salt sensitive rats (Dahl S) or spontaneously hypertensive rats (SHR) is linked to intrinsic changes in the brain that favour increased Na+ entry into the cerebrospinal fluid (CSF) followed by increases in sympathetic hyperactivity and hypertension (Huang et al 2004). Similar responses are observed in salt resistant and Wistar rats that receive an intracerebroventricular (icv) infusion of Na+ rich artificial cerebrospinal fluid (aCSF) (Huang et al 2001, 2006). Downstream to increased CSF[Na+], a pathway has been described involving mineralocorticoid receptors (MRs), benzamil sensitive Na+ channels, “ouabain”, and angiotensin II type 1 receptors (AT1-R) (Huang et al 1998, Zhao et al 2001, Wang and Leenen 2003, Huang et al 2008). Blood pressure (BP) responses to increased CSF[Na+] may involve activation of AT1-R in the subfornical organ (SFO) as the BP response to injection of NaCl into a lateral ventricle can be blocked by AT1-R blockade in the SFO (Rohmeiss et al 1995a). The role of aldosterone and AT1-R in the SFO was investigated in mediating the BP and heart rate (HR) response to increases in CSF[Na+] and local [Na+]. Results show that infusion of 0.45M and 0.6M Na+ rich aCSF into the SFO increases BP but not HR. The BP is unchanged by infusion of a mannitol solution osmotically equivalent to 0.6M Na+ rich aCSF indicating that the SFO is Na+ sensitive. The BP response to a lower concentration of Na+ (0.45M) is enhanced by prior infusion of aldosterone while BP response to 0.6M is not further enhanced suggesting that the SFO may have maximal responsiveness to acute increases in [Na+] at 0.6M. The BP responses to Na+ rich aCSF in the SFO and the enhancement of those responses by aldosterone can be blocked by infusion of the AT1-R blocker Candesartan in the SFO. This response appears therefore to be mediated in the SFO through AT1-R activation, likely through Ang II release in the SFO. ICV infusion of Na+ rich aCSF increases BP but not HR and this response is partially blocked by infusion of the AT1-R blocker Candesartan in the SFO. This indicates that nearly half the BP responses to icv infusion of Na+ rich aCSF is mediated through AT1-R activation in the SFO. Lastly, contrary to icv, PVN and MnPO studies (Huang and Leenen 1996, Budzikowski and Leenen 2001, Gabor and Leenen 2009) ouabain in the SFO does not increase BP or HR. In conclusion, these results show that the SFO is Na+ sensitive and mediates half the BP responses to changes in CSF[Na+] through a mechanism that involves AT1-R activation. The SFO is further sensitized to Na+ by aldosterone presumably through its genomic effects. Lastly, ouabain in the SFO does not increase BP or HR suggesting that endogenous ouabain in the SFO is not involved in modulating BP or HR responses.
7

Efeitos da restrição alimentar materna sobre a prole de ratas Wistar. Avaliações teratogênicas clássicas e de imunoteratologia / Effects of maternal feed restriction in Wistar rats offspring: Evaluations by classical and immunoteratology protocols

Dipe, Vânius Vinícius 11 August 2009 (has links)
A Organização Mundial da Saúde revela que mais de 20 milhões de crianças nascem com baixo peso ao nascimento em todo o mundo, sendo a má nutrição o principal fator desencadeante. Estudos realizados nas duas últimas décadas mostram que o status nutricional materno pode ser crítico no desenvolvimento de teratogenicidade; porém não há trabalhos que comprovem a associação entre restrição alimentar materna e a ocorrência de malformações. No entanto, o conceito de teratogênese não se restringe apenas às malformações estruturais logo após o nascimento, também são consideradas alterações funcionais, como aquelas comportamentais ou no sistema imune, entre outras, que podem se manifestar somente na maturação pós-natal. Assim, o presente trabalho visou verificar os efeitos da restrição alimentar materna durante a gestação, avaliando-a por meio tanto do protocolo clássico de teratogenicidade, como através de protocolos de imunoteratologia, analisando-se neste caso, as possíveis alterações no sistema imune da prole após o desmame e também na idade adulta. Foram empregadas ratas Wistar prenhes, divididas em cinco grupos iguais, um controle (CO) no qual os animais receberam ração ad libitum, e nos demais grupos, as fêmeas foram submetidas à restrição alimentar, do 6º ao 17º dia de gestação, diminuindo-se em 15 (E15), 40 (E40), 55 (E55) e 70% (E70) da quantidade de ração consumida pelos animais do grupo CO. Por meio do protocolo clássico de teratogenicidade, verificaram-se as possíveis alterações ósseas e viscerais sobre a prole. Empregou-se ainda o protocolo de imunoteratologia, no qual foram realizados testes nas proles tanto ao desmame como na idade adulta, e aferiu-se os seguintes parâmetros: hemograma, peso relativo do timo e do baço, celularidade do baço e da medula óssea; a imunidade inata: atividade de macrófagos peritoneais por meio da fagocitose, produção de peróxido de hidrogênio e óxido nítrico; a imunidade humoral: produção de anticorpos pelo ensaio do plaque forming cell e a titulação de anticorpos anti-eritrócitos de carneiro; e a imunidade celular: avaliação da hipersensibilidade tardia. Em relação às avaliações teratogênicas clássicas, estas mostraram haver, naqueles filhotes provenientes das ratas submetidas às restrições alimentares (E40, E55 e E70), diminuição no peso ao nascimento, aumento da proporção de fetos mortos até uma hora após o nascimento e aumento do número de fetos com ureter sinuoso; no entanto, não foi constatada a ocorrência de malformações graves, que pudessem colocar em risco a vida do concepto. Já as avaliações pós-natais revelaram diminuição no ganho de peso, do nascimento até a idade adulta, das proles provenientes das ratas do grupo E70. Em relação às alterações imunoteratogênicas, houve aumento no peso relativo do timo e da resposta imune celular nas proles destas mães submetidas à maior restrição alimentar, quando estes animais foram avaliados aos 21 dias de idade. Quando realizou-se este estudo nas proles com 70 dias (idade adulta), os filhotes provenientes de mães das diferentes restrições alimentares apresentaram aumento da resposta imune humoral; além disto aqueles filhotes de mães E70, mostraram aumento da resposta imune celular. Os dados apresentados na presente pesquisa permitem sugerir que a restrição alimentar em ratas Wistar durante a organogênese fetal, embora não promova malformações estruturais, produz prole de menor peso ao nascimento e é capaz de gerar alterações significantes no sistema imune dos filhotes. / The World Health Organization has reported that more than 20 million children worldwide are born with low birth weight, with malnutrition the main triggering factor. Studies in the past two decades have shown that maternal nutritional status may be critical in the development of teratogenicity, but there are no studies that directly relate maternal feed restriction and malformation. However, teratogenecity is not restricted only to structural abnormalities at birth, but may also include functional changes, such as behavioral or immune system alterations, among others, which may manifest themselves only in the postnatal period of maturation. Thus, this work aimed to assess the effects of maternal food restriction in pregnant rats using classical and immunoteratogenic protocols to evaluate the offspring. Thus, possible immune system changes were evaluated in the offspring after weaning and after maturation. Pregnant females were divided into five groups, a control group (CO) in which the animals received feed ad libitum, and four other groups, in which females were fed a restricted amount based on the total ingested by controls: 15% (E15), 40% (E40), 55% (E55) and 70% (E70) during days 6 to 17 of gestation. Rats were humanely euthanized and teratogenicity was evaluated using skeletal and visceral measurements. Immunoteratogenic effects were determined in weaned and mature offspring (10 weeks) using blood, thymus and spleen relative weights and spleen and bone marrow cellularity. In addition, innate immunity was determined using activity of peritoneal macrophages through phagocytosis, and production of hydrogen peroxide and nitric oxide. Humoral immunity was determined using production of antibodies by the plaque-forming cell assay and titers of anti-sheep red blood cells. Cellular immunity was determined by evaluating delayed type hypersensitivity. Traditional teratogenic indices showed that pups from females subjected to feed restriction (E40, E55 and E70) had a decrease in birth weight, an increased proportion of dead fetuses up to one hour after birth, and an increase in the number of fetuses with kinked ureter. No major malformations serious enough to threaten the life of the conceptus were observed. There was a postnatal decrease in weight gain in offspring from mothers of group E70 from birth to adulthood. There was also immune system changes, with an increase in the thymus relative weight (E40, E55, E70) and cellular immune response in offspring (21 days of age). When offspring were evaluated after maturation, those pups from mothers with feed restriction had increased humoral immune responses; in addition offspring from the E70 group showed an increase in cellular immune response. The data presented in this study suggest that feed restriction in Wistar rats during organogenesis does not promote structural malformations, but instead results in offspring with lower birth weights, and also promoted significant changes in the immune system of rat pups.
8

Influência da insulina sobre a autofagia em modelo experimental de diabetes / Insulin influence upon autophagy in experimental model of diabetes

Sunahara, Karen Krist Sary 11 August 2014 (has links)
O diabetes mellitus (DM) é caracterizado por hiperglicemia associada à falta ou à ineficiência da insulina. DM também é marcado por alterações em diversos processos celulares que precisam ser mais bem entendidos. Estudou-se a via da autofagia em diferentes macrófagos, verificando se o tratamento com insulina é capaz de modular esse processo. Foram estudados macrófagos derivados da medula óssea (BMM), do lavado broncoalveolar (LBA) e do tecido esplênico de ratos Wistar, machos, diabéticos (aloxana, 42 mg/kg, i.v., 10 dias), ratos diabéticos tratados (insulina 4UI, s.c.) e respectivos controles. Para caracterização do modelo e avaliação do efeito da insulina sobre o processo autofágico, as seguintes análises foram realizadas: (a) glicemia, número de leucócitos no sangue periférico, número de células do LBA; (b) concentrações de citocinas: interleucina (IL)-1beta, fator de necrose tumoral (TNF)-alfa, IL-6, IL-4, IL-10, cytokine-induced neutrophil chemoattractant (CINC)-1 e CINC-2 no sobrenadante do LBA pela técnica de ELISA; (c) caracterização de macrófago alveolar (MA) do LBA quanto a antígenos de superfície (MHCII, pan-macrophage KiM2R, CD11b) e marcadores autofágicos (proteína de cadeia leve associada a microtúbulo (LC)3 , gene/proteína relacionado à autofagia (ATG) pela técnica de citometria de fluxo e microscopia confocal ; (d) estudo dos macrófagos diferenciados, a partir da medula óssea, por citometria de fluxo e microscopia confocal; (e) estudo da arquitetura do baço pela técnica de imuno-histoquímica associada à microscopia confocal. Avaliando os resultados em conjunto, a via autofágica parece ser de extrema importância e de capacidade inovadora para alvo terapêutico. Observou-se que a insulina exerceu efeitos antagônicos sobre os macrófagos de tecidos diferentes: aumentou a expressão LC3 nos macrófagos recuperados por LBA e não conseguiu alterar a atividade autofágica em macrófagos da polpa vermelha do baço em ratos diabéticos. Os BMM originários de ratos diabéticos comportaram-se de maneira contrária aos do animal controle: os BMM tipo M1 tiveram o conteúdo de LC3 diminuído, enquanto os M2 tiveram o conteúdo autofágico aumentado. O tratamento com insulina nos ratos diabéticos não alterou o nível do conteúdo LC3 dos BMM, mesmo após uma semana de cultura in vitro. Concluímos, assim, que o tratamento com dose única de insulina foi capaz de induzir a autofagia em macrófagos alveolares, mas insuficiente para resgatar os níveis basais da autofagia em macrófagos da medula óssea e da polpa vermelha do baço / Diabetes mellitus (DM) is characterized by hyperglycemia associated to a lack or ineffectiveness of insulin. DM is marked by changes in several cellular processes that need to be better understood. Autophagy pathway in macrophages from different tissues was studied with the purpose to verify whether treatment with insulin is capable of modulating this process. Bone marrow derived macrophages (BMM), bronchoalveolar lavage (BAL), and splenic tissue macrophages from Wistar rats, diabetic (alloxan, 42 mg/kg, iv, 10 days) and diabetic rats treated with insulin were studied. To characterize the model and evaluate the effect of insulin upon the autophagic process, the following analyzes were performed: (a) glucose levels, number of leukocytes in peripheral blood, BAL cell number; (b) concentrations of cytokines (interleukin (IL)-1beta, tumor necrosis factor (TNF)-alfa, IL-6, IL-4, IL-10, cytokineinduced neutrophil chemoattractant (CINC)-1 and CINC-2 in the supernatant of BAL fluid by ELISA; (c) characterization of BAL alveolar macrophage (AM) surface antigens (MHCII, pan macrophage marker KiM2R, CD11b) and autophagic markers (microtubule-associated protein light chain (LC)3, gene/protein associated to autophagy (ATG) by flow cytometry and confocal microscopy (d) study of macrophages diferenciated from bone marrow by flow cytometry and confocal microscopy; (e) the architecture of spleen and macrophages from red pulp by immunohistochemical techniques associated to confocal microscopy. Evaluating these results together, the autophagic pathway appears to be innovative for therapeutic target. In this study, it was observed that insulin exerted diverse effects on macrophages from different tissues: increased expression of LC3 in AM recovered from BAL and was unable to change the autophagic activity of macrophages from the red pulp of the spleen in diabetic rats. BMM from diabetic rats behaved in an antagonistic way compared to control animals: BMM M1 type decreased their autophagy content while M2 macrophages increased autophagic levels and insulin treatment did not alter the level of LC3 expression. In conclusion, treatment with a single dose of insulin was able to induce autophagy in alveolar macrophages, but insufficient for recovering baseline levels of autophagy in bone marrow derived macrophages and macrophages from the red pulp of the spleen
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Avaliação do estresse oxidativo em humanos e em animais suplementados com ácidos graxos polinsaturados omega-3 / Evaluation of oxidative stress in humans and animals supplemented with Omega-3 polyunsaturated fatty acids

Monteiro, Vania Claudia Barros 24 April 2007 (has links)
Ácidos graxos polinsaturados Omega-3 (n-3 PUFA) tais como o ácido eicosapentaenóico (C20:5 n-3, EPA) e docosahexaenóico (C22:6 n-3, DHA) reduzem a concentração plasmática de triacilgliceróis em humanos. Entretanto, uma alta proporção desses ácidos graxos na dieta poderia favorecer a susceptibilidade das células à peroxidação, aumentando o risco de desenvolvimento de doenças cardiovasculares. Embora modelos animais não sejam recomendados para avaliar o efeito de n-3 PUFA nas lipoproteínas plasmáticas, estes têm sido amplamente utilizados como modelo para avaliação de dano oxidativo. Diferenças nos procedimentos metodológicos também têm gerado dificuldade na comparação de resultados. Desta forma, o objetivo deste estudo foi aplicar os mesmos procedimentos metodológicos para comparar o efeito da suplementação de n-3 PUFA nos biomarcadores plasmáticos de estresse oxidativo utilizando um modelo humano e um modelo animal. Indivíduos foram aleatoriamente distribuídos em dois grupos num delineamento paralelo duplo cego e receberam uma suplementação de 460,0 mg/dia de n-3 PUFA (OMEGA) contendo 240,0 mg de EPA + 160,0 mg de DHA + 60,0 mg de outros n-3 PUFAs, ou óleo de soja (PLACEBO) durante 6 semanas. Ratos Wistar também foram distribuídos em dois grupos e receberam uma dieta contendo 192,5 mg/dia de n-3 PUFA (FO) sendo 116,3 mg de EPA + 61,5 mg de DHA + 14,7 mg de outros n-3 PUFAs ou óleo de soja (SO) durante 3 semanas. Indivíduos do grupo OMEGA apresentaram maior concentração de malondialdeído (MDA) no plasma medido por TBARS quando comparado aos respectivos valores no baseline. A suplementação com n-3 PUFA não alterou a concentração plasmática de α-tocoferol e a atividade antioxidante determinada pelo método DPPH. Apesar dos animais terem recebido doses 10 vezes maiores de n-3 PUFA (2,9 mg/kcal) quando comparadas aos humanos (0,3 mg/kcal) não foram observadas alterações entre os grupos FO e SO para as concentrações de MDA no plasma e no homogenato de cérebro. Em resumo, pode-se sugerir que o modelo animal usado neste estudo parece não ser o mais adequado para avaliar o estresse oxidativo após intervenções dietéticas com n-3 PUFAs em função de diferenças no metabolismo e nos mecanismos de proteção antioxidante observados entre os dois modelos. / Omega-3 polyunsaturated fatty acids (n-3 PUFA) such as eicosapentaenoic (C20:5 n-3, EPA) and docosahexaenoic (C22:6 n-3, DHA) reduce plasma triacylglycerol concentration in humans. However, higher proportion of these fatty acids in the diet could raise cells lipoperoxidation susceptibility, increasing the cardiovascular disease risk. Although animal models are not recommended to evaluate the effect of n-3 PUFA in plasma lipoproteins, they have been widely used as model for oxidative damage. Difference in methodological proceedings has also caused difficulties to compare data among assays. Thus, the objective of this study was to apply the same methodology to investigate the effect of n-3 PUFA supplementation on oxidative biomarkers in animal and human model. Individuals were randomly assigned in two groups in a parallel double blind design and received a supplement of 460.0 mg/day n-3 PUFA (OMEGA) containing 240.0 mg EPA + 160.0 mg DHA + 60.0 mg other n-3 PUFAs, or soybean oil (PLACEBO) during 6 weeks. Wistar rats were also assigned in two groups and received a diet containing 192.5 mg/day n-3 PUFA (FO) containing 116.3 mg EPA + 61.5 mg DHA + 14.7 mg other n-3 PUFAs or soybean oil (SO) for 3 weeks. Individuals in OMEGA group showed higher malondialdehyde (MDA) concentration in plasma measured by TBARS when compared to their baseline values. N-3 PUFA supplementation did not change plasma α-tocopherol concentration and antioxidant activity determined by DPPH method. Although animals have received a 10-fold higher dose of n-3 PUFA (2.9 mg/ kcal) than humans (0.3 mg/kcal), no alteration was observed between FO and SO groups for plasma and brain homogenate MDA concentration. In summary, it can be suggested that the model used in this study doesn\'t seem appropriate to evaluate oxidative stress after dietetic interventions with n-3 PUFA due to physiological differences involved in lipid metabolism and antioxidant protection observed between both models.
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A influência dos pontos de acupuntura Zusanli (E36) e Sanyinjiao (BP6) no desenvolvimento de lesões hepáticas induzidas por Tioacetamida, em ratos Wistar / The influence of the acupuncture points Zusanli (ST36) and Sanyinjiao (SP6) in the development of hepatic lesions induced by thioacetamide in Wistar rats

Rodrigues, Alexandro dos Santos 18 December 2009 (has links)
O fato da acupuntura ser atualmente considerada eficaz no tratamento de muitos processos patológicos e do fígado ser um órgão alvo de muitas enfermidades tanto em animais como em seres humanos, motivou a realização deste estudo que tem por objetivo verificar o efeito da eletroacupuntura durante a progressão de lesões hepáticas e o seu relacionamento com o funcionamento do órgão através da análise concomitante de marcadores sanguíneos de lesões hepáticas (MSLH). O trabalho foi realizado em ratos albinos (Wistar), machos, com um peso aproximado de 250g, identificados e distribuídos em 7 lotes (CP, CT, CI, E36, E36s, BP6, BP6s), N= 10. Os animais dos lotes: CP, CT e CI foram usados como controle; CP na determinação dos MSLH: alanina aminotransferase (ALT), aspartato aminotransferase (AST), - glutamil transferase (GGT), fosfatase alcalina (ALPK), albumina (ALB), proteína total (TP) e bilirrubina total; CT cujos animais receberam apenas o agente hepatotóxico tioacetamida (25 mg/100g) por via intraperitoneal três vezes por semana, durante 7 semanas e o lote CI, no qual os animais, além dos mesmos procedimentos de CT, também foram submetidos ao anestésico usado no experimento (isoflurano) pelo tempo de 20 minutos, objetivando analisar se esse anestésico teve alguma influência nos resultados do trabalho. Quanto aos demais grupos, E36 recebeu os mesmos procedimentos de CI e seus componentes foram tratados com eletroacupuntura no ponto Zusanli (E-36). E36s recebeu procedimentos similares aos de E36, porém a eletroestimulação foi aplicada em um não-ponto de acupuntura (E36 Sham) localizado próximo ao E36 verdadeiro. Os animais de BP6 tiveram os mesmos procedimentos de E36 diferindo somente na eletroacupuntura, que foi aplicada no ponto Sanyinjiao (BP-6). No lote BP6s os procedimentos foram os mesmos realizados em BP6, porém a eletroestimulação foi realizada em um nãoponto de acupuntura (BP6 Sham) localizado próximo ao ponto BP6 verdadeiro. Numa etapa seguinte, os animais dos nove grupos, tiveram seus fígados coletados para estudo histológico, tendo sido comparado os parâmetros bioquímicos obtidos, com objetivo de analisar se as alterações morfológicas e funcionais dos fígados tiveram influência da eletroacupuntura. Resultados: Os MSLH apresentaram como resultados: marcador ALB nos lotes: CP (2,97±0,3529) com CI(2,46±0,3134) e marcador TP nos lotes CP (6,53±0,2452) com CI(5,73±0,4057) provando haver interferência do isoflurano; marcador ALB nos lotes CI com BP6 (2,84±0,2675) e BP6 com E36s (2,4±0,2828), marcador ALT nos lotes CI com BP6 e BP6 com E36s e marcador AST nos lotes BP6 com E36s, todos provando e eficácia do ponto de acupuntura BP6. Os resultados histológicos confirmaram a atuação da tioacetamida (TAA) nos animais (exceto os do lote CP), através das seguintes lesões: inflamação focal, apoptose, necrose em saca-bocado (Piecemeal-necrosis), necrose e inflamação portal, para as análises em Hematoxilina-Eosina e expansão fibrosa e pontes de colágeno para as colorações em Picrossirius. Essas lesões foram achadas nos lotes: CT, CI, E36s, BP6s, E36 e BP6, porém, nos dois últimos ocorreram em menor grau indicando a atuação de eletroacupuntura sobre a morfologia hepática. / The fact o acupuncture have being considered an efficient method to treat lots of diseases and, being the liver, in men and animals, a common susceptible organ, this research was inspired to verify the electroacupuncture effect in hepatic lesion progression and its relationship with the liver performance at the same time that sanguinenous hepatic lesions markers (MSLH) was analysed. Each one identified, male wistar rats arround 250g was ditribucted in 7 (seven) groups, N=10: CP, CT, CI, ST36, ST36s, SP6 and SP6s. The first three was control-groups: CP to be these MSLH reference: alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALKP), albumin.(ALB), total protein (TP) and total bilirubin (TB); CT had the animals receiving only the hepatotoxic agent thioacetamide (25mg/100g) interperitoneal pathway, 3 (three) a week, for 7 (seven) weeks and CI had the same last proceedment increased for 20 minutes in isoflurane anesthetic to verify if interferences occures or not. About the others groups, we had ST36 receiving the same CI proceedments and treated by Zusanli (St-36) electroacupuncture point; ST36s again, but in a false-point (Sham ST36) next the real one. Groups SP6 and SP6s had the analogous treatment to points Sanyinjiao (SP-6) and its no-point. The next step was collect the nine groups livers and study them histologically. They was compared with CP references to mesuere some probable electroacupuncture influence in morphological and functional hepatic processes. MSLH results was: ALB in groups CP (2,97±0,3529) with CI (2,46±0,3134) and sanguinenous marker TP in groups CP (6,53±0,2452) with CI (5,73±0,4057), proving isoflurane interference; ALB in gropus CI with SP6 (2,84±0,2675) and in gropus SP6 with ST36s (2,4±0,2828), sanguinenous marker ALT in groups CI with SP6 and in groups SP6 with ST36 and sanguinenous marker AST in groups SP6 with ST36s, all of them proving the SP6 electroacupuncture point efficacy. The histological results conffirmed thioacetamide (TAA) actuation in animals (except group CP), through these lesions: focalized inflammation, apoptosis, piecemeal-necrosis, necrosis and portal-inflammation to hematoxylin and eosin analysis and fibrosis expansion and collagen bridges to Picrosirius colorations. These lesions was discovered in groups CT, CI, ST36s, SP6s, ST36 and SP6s. However, in the last two group was discovered less then the others, indicating electroacupuncture efficience in hepatic morphology.

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