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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

Pré-condicionamento com ternatina no infarto do miocárdio induzido por isoproterenol em ratos / Preconditioning with ternatina on myocardial infarction induced by isoproterenol in rats

Leão Filho, Carmelo Silveira Carneiro January 2011 (has links)
LEÃO FILHO, Carmelo Silveira Carneiro. Pré-condicionamento com ternatina no infarto do miocárdio induzido por isoproterenol em ratos. 2011. 76 f. Dissertação (Mestrado em Cirurgia) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2011. / Submitted by denise santos (denise.santos@ufc.br) on 2014-02-18T13:09:00Z No. of bitstreams: 1 2011_dis_cscleãofilho.pdf: 1319879 bytes, checksum: 5583a1508967a0ad65f7fad54289dda8 (MD5) / Approved for entry into archive by denise santos(denise.santos@ufc.br) on 2014-02-18T13:10:18Z (GMT) No. of bitstreams: 1 2011_dis_cscleãofilho.pdf: 1319879 bytes, checksum: 5583a1508967a0ad65f7fad54289dda8 (MD5) / Made available in DSpace on 2014-02-18T13:10:18Z (GMT). No. of bitstreams: 1 2011_dis_cscleãofilho.pdf: 1319879 bytes, checksum: 5583a1508967a0ad65f7fad54289dda8 (MD5) Previous issue date: 2011 / Acute myocardial infarction (AMI) is one of the most common causes of death in our country. As population ages, such illness have its prevalence rates increased. In order to analyse drug effects over myocardial lesions as a result of AMI, the myocardial infarction induction model by means of the administration of isoproterenol in rats is one of the most used at all, given the capability of that substance of mimicking the myocardial injury observed in humans. In the present study, preconditioning with intra-peritoneal ternatin, at a dose of 1 mg/kg was used. Fourteen consecutive days were assessed in the isoproterenol-induced MI (120 mg/kg) in Wistar rats. Myocardial lesions induced by isoproterenol was indicated by the rise in biochemical markers levels, such as SGOT (serum glutamic oxaloacetic transaminase) and troponin I, reduction in the activity of catalase enzyme in the myocardial tissue, as well as by histopathological changes assessed in the apex of the left ventricle. It was also evaluated mortality rates, hemoglobin and SGPT (serum glutamic pyruvic transaminase) serum concentrations, leukocytes, neutrophils counts and renal function. Preconditioning with ternatin unveiled protective effects within the myocardial infarction induced by isoproterenol in rats, once it diminished mortality rates, attenuated SGOT and troponin I concentrations, preserved catalase levels in the myocardium and diminished histopathological changes in the apex of the left ventricle Possible pathways accountable for such good results, reducing the degree of myocardial injury in this experimental essay, might be related to the antioxidant properties attributable to ternatin. / O infarto agudo do miocárdio (IAM) é uma das principais causas de morte em nosso país. Com o envelhecimento da população a tendência é que se aumente a incidência desta afecção. Para se estudar efeitos de drogas sobre a lesão miocárdica decorrente de IAM, um dos modelos experimentais mais utilizados é a indução de infarto do mocárdio (IM) com administração de isoproterenol em ratos, uma vez que esta substância causa uma lesão miocárdica semelhante à observada em IAM nos humanos. Nesse estudo o pré-condicionamento com ternatina administrada por via intraperitoneal, na dose de 1 mg/kg do animal, por catorze dias consecutivos, foi avaliado no IM induzido por isoproterenol (120 mg/kg do animal) em ratos Wistar. A lesão miocárdica induzida pelo isoproterenol foi indicada pela elevação de marcadores bioquímicos, como transaminase glutâmico-oxalacética (TGO) e troponina I, redução da atividade da enzima catalase no tecido miocárdico, bem como por alterações histopatológicas avaliadas na região do ápice do ventrículo esquerdo. Avaliou-se ainda a mortalidade, as concentrações séricas de transaminase glutâmico-pirúvica (TGP), hemoglobina, contagem de leucócitos e neutrófilos e marcadores da função renal. O pré-tratamento com ternatina apresentou efeitos protetores no infarto do miocárdio induzido por isoproterenol em ratos, uma vez que dimunuiu a taxa de mortalidade, atenuou as elevações de TGO e troponina I; preservou a atividade da enzima catalase e reduziu o grau de alterações histopatológicas. Possíveis mecanismos de ação responsáveis pelos efeitos benéficos em reduzir o grau de lesão miocárdica neste modelo experimental podem estar relacionados a propriedades antioxidantes da ternatina.
2

Isoproterenol and inotropism in guinea pig papillary muscle /

Li, Tung January 1979 (has links)
No description available.
3

Efeitos vasculares da hiperativação beta-adrenérgica associados à ativação do sistema-renina-angiotensina-aldosterona / Involvement of renin-angiotensin-aldosterone system activation on the vascular effects of beta-adrenoceptor hyperactivation

Victorio, Jamaira Aparecida, 1987- 02 March 2014 (has links)
Orientador: Ana Paula Couto Davel / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T14:07:47Z (GMT). No. of bitstreams: 1 Victorio_JamairaAparecida_M.pdf: 1155350 bytes, checksum: eab5bb2760f0d9abd7c5e93ac2b95b51 (MD5) Previous issue date: 2014 / Resumo: A hiperativação dos receptores ß-adrenérgicos (ß-AR) tem importante papel na patogênese de doenças cardiovasculares que cursam com hiperatividade simpática. Dentre os seus efeitos, sugere-se a indução da síntese e liberação de angiotensina II e de aldosterona sistemicamente. A hiperativação dos receptores ß-AR pode ser mimetizada pelo tratamento crônico com isoproterenol (ISO). Já foi demonstrado que o antagonismo do receptor AT1 de angiotensina II ou do receptor de mineralocorticoides (MR) previne parcialmente o remodelamento cardíaco induzido pelo ISO. Entretanto, ainda não está elucidado o envolvimento da angiotensina II e da aldosterona nos efeitos vasculares causados pela hiperativação dos receptores ß-AR. Assim, o objetivo do presente estudo foi investigar as vias de sinalização dos receptores AT1 e MR nas alterações vasculares causadas pelo tratamento por 7 dias com ISO em aorta de ratos, assim como os mecanismos envolvidos. Ratos Wistar (3 meses) foram tratados com ISO (0,3 mg/kg/dia, s.c.) ou veículo (CT) e co-tratados ou não com o antagonista do receptor AT1 losartan (LOS; 40 mg/kg/dia) ou com o antagonista do receptor MR espironolactona (ESP; 200 mg/kg/dia). O tratamento com ISO causou hipertrofia ventricular sem alterações hemodinâmicas, e o co-tratamento com LOS ou ESP atenuaram o remodelamento ventricular observado. Na aorta do grupo ISO observou-se um aumento da resposta máxima à fenilefrina associado à redução da biodisponibilidade de óxido nítrico (NO) e aumento de ânion superóxido, os quais foram prevenidos pelo co-tratamento com ESP, mas não com LOS. O efeito preventivo da ESP sobre a reatividade vascular da aorta dos ratos ISO foi acompanhado de aumento da expressão proteica da HSP90, a qual foi reduzida no grupo ISO. Além disso, a ESP preveniu o aumento da expressão proteica de ß-arrestina, Gai, p-Src, ERK1/2, p- ERK1/2 e gênica de osteopontina na aorta deste grupo. As concentrações plasmáticas de corticosterona ou aldosterona não foram alteradas entre os grupos avaliados. Em conjunto, os dados sugerem que o antagonismo do receptor MR com o uso de espironolactona previne o aumento da resposta contrátil à fenilefrina observada em aorta de ratos tratados com ISO, associado a: aumento da biodisponibilidade de NO e redução do estresse oxidativo; aumento da expressão de HSP90, a qual estabiliza a forma dimérica da eNOS; e prevenção do aumento da expressão proteica de ß- arrestina, Gai1,2, p-Src, ERK1/2 e p-ERK1/2 e gênica de osteopontina, vias de sinalização de estresse oxidativo e prejuízo da função endotelial / Abstract: ß-adrenergic (ß¿AR) receptors overstimulation plays an important role in the pathogenesis of cardiovascular diseases concurrent with sympathetic overactivity. It has been suggested to increase plasma levels of angiotensin II and aldosterone. In line with this, angiotensin II/AT1 receptor or mineralocoticoid (MR) receptor antagonism partially prevents the cardiac remodeling induced by ß-AR overstimulation mediated by isoproterenol (ISO) administration. However the implication of angiotensin II or aldosterone on vascular effects provoked by ß¿AR overstimulation is not yet elucidated. So, the aim of the present study was to investigate the AT1 and MR receptor signaling pathway on vascular alterations caused by 7-day ISO treatment on rat aorta, as well as the mechanisms involved. For this, male Wistar rats (3-month-old) were treated with ISO (0.3 mg/kg/day, s.c.) or vehicle (CT) and co-treated or not with AT1 antagonist losartan (LOS; 40 mg/kg/day, v.o.) or MR receptor antagonist spironolactone (ESP; 200 mg/kg/day, v.o.). The ISO treatment resulted in ventricular hypertrophy without hemodynamic alterations, and LOS or ESP co-treatment attenuated the ventricular remodeling of ISO group. ISO aorta showed an increased phenylephrine maximum response associated with a decreased nitric oxide (NO) bioavailability and an increased in superoxide anion; both effects were prevented by ESP co-treatment, but not by LOS. Beneficial effects of ESP on vascular reactivity of aorta from ISO-treated rats were accompanied by an increased HSP90 protein expression, which was reduced in ISO group. Moreover, ESP prevented the increased protein expression of ß-arrestin, Gai, p- Src, ERK1/2 and p-ERK1/2 and osteopontina gene expression in the aorta from ISO group. Plasma corticosterone and aldosterone were not changed between the groups. In conclusion, our results suggest that spironolactone, an MR receptor antagonist prevented the increased phenylephrine contractile response in aorta from ISO-treated rats, associated with increased NO bioavailability and decreased oxidative stress; increased expression of HSP90 and; prevented the increase of ß-arrestin, Gai1,2, p-Src, ERK1/2 and p-ERK1/2 and osteopontin induced by ß-adrenergic overstimulation. These results suggest that the vascular effects induced by ISO in aorta are mediated by a MR activation / Mestrado / Fisiologia / Mestra em Biologia Funcional e Molecular
4

Size dependent effects of gold nanoparticles in ISO-induced hyperthyroid rats

Zhang, J., Xue, Y., Ni, Y., Ning, F., Shang, Lijun, Ma, A. 19 July 2018 (has links)
Yes / In this study, we applied different sizes of gold nanoparticles (Au-NPs) to isoproterenol (ISO)-induced hyperthyroid heart disease rats (HHD rats). Single dose of 5, 40, 100 nm Au-NPs were injected intravenously. Cardiac safety tests were evaluated by cardiac marker enzymes in serum and cardiac accumulation of Au-NPs were measured by ICP-MS. Our results showed that size-dependent cardiac effects of Au-NPs in ISO-induced hyperthyroid rats. 5 nm Au-NPs had some cardiac protective effect but little accumulation in heart, probably due to smaller size Au-NPs can adapt to whole body easily in vivo. Histological analysis and TUNEL staining showed that Au-NPs can induce pathological alterations including cardiac fibrosis, apoptosis in control groups, however they can protect HHD groups from these harmful effects. Furthermore, transmission electron microscopy and western blotting employed on H9C2 cells showed that autophagy presented in Au-NPs treated cells and that Au-NPs can decrease LC3 II turning to LC3 I and decrease APG7 and caspase 12 in the process in HHD groups, while opposite effects on control groups were presented, which could be an adaptive inflammation reacts. As there are few animal studies about using nanoparticles in the treatment of heart disease, our in vivo and in vitro studies would provide valuable information before they can be considered for clinical use in general.
5

Pré-condicionamento com óleo essencial de Alpinia zerumbet no infarto do miocárdio induzido por isoproterenol em ratos / Preconditioning with essential oil of Alpinia zerumbet on myocardial infarction induced by isoproterenol in rats

Lobo Filho, Heraldo Guedes January 2011 (has links)
LOBO FILHO, Heraldo Guedes. Pré-condicionamento com óleo essencial de Alpinia zerumbet no infarto do miocárdio induzido por isoproterenol em ratos. 2011. 91 f. Dissertação (Mestrado em Cirurgia) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2011. / Submitted by denise santos (denise.santos@ufc.br) on 2014-02-20T15:38:46Z No. of bitstreams: 1 2011_dis_hglobofilho.pdf: 844447 bytes, checksum: ff041843cc9e9cde7177f8b37575a348 (MD5) / Approved for entry into archive by denise santos(denise.santos@ufc.br) on 2014-02-20T15:39:14Z (GMT) No. of bitstreams: 1 2011_dis_hglobofilho.pdf: 844447 bytes, checksum: ff041843cc9e9cde7177f8b37575a348 (MD5) / Made available in DSpace on 2014-02-20T15:39:14Z (GMT). No. of bitstreams: 1 2011_dis_hglobofilho.pdf: 844447 bytes, checksum: ff041843cc9e9cde7177f8b37575a348 (MD5) Previous issue date: 2011 / Acute myocardial infarction (AMI), defined as death of the cardiac muscle after an ischemic process, is worldwide known for its frequent diagnosis within hospitalized patients in modern industrialized countries. Myocardial infarction induced by isoproterenol (ISO) in rats is a very useful assay to study the effect of drugs on myocardial injury as a result of AMI, once its administration is responsible for a post-infarction human-like myocardial lesion. In this study, essential oil of Alpinia zerumbet (EOAZ), at a dose of 100 mg / kg, administered for fourteen consecutive days, was assessed in myocardial infarction induced by ISO (150 mg / kg bodyweight) in Wistar rats. The myocardial injury induced by ISO was indicated by elevated markers of myocardial injury, such as AST and troponin I, reduced levels of catalase and glutathione, as well as histopathological changes evaluated at the apex of the left ventricle. It was also evaluated mortality, hemoglobin levels, leukocyte and neutrophil counts and levels of markers of renal function. Pretreatment with the EOAZ showed protective effects on myocardial infarction induced by isoproterenol in rats, as attenuated the elevation of AST, Troponin I, attenuated the increased number of neutrophils; preserved the levels of catalase in the myocardium and preserved glutathione levels in the myocardium. However, do not exert any effects on mortality, weight variation of animals, serum ALT, serum levels of hemoglobin and white blood cell count, serum markers of renal function, histopathological changes in left ventricular apex. The probable mechanisms of action responsible for the beneficial effects of this oil in reduce the degree of myocardial injury in this experimental model may be related to antioxidant properties and increased levels of nitric oxide. / O infarto agudo do miocárdio (IAM), definido como a morte do músculo cardíaco decorrente de isquemia, é um dos diagnósticos mais comuns em pacientes hospitalizados nos países industrializados. Para se estudar efeitos de drogas sobre a injúria miocárdica decorrente de IAM, um dos modelos experimentais bastante utilizado é a indução de infarto do mocárdio (IM) com administração de isoproterenol em ratos, uma vez que esta substância causa uma lesão miocárdica semelhante a observada em IAM nos humanos. Nesse estudo o óleo essencial de Alpinia zerumbet, na dose de 100 mg/kg de peso, administrado por catroze dias consecutivos, foi avaliado no infarto do miocárdio induzido por isoproterenol (150 mg/kg de peso do animal) em ratos wistar. A injúria miocárdica induzida pelo isoproterenol foi indicada pela elevação de marcadores de injúria miocárdica, como TGO e troponina I, redução dos níveis de catalase e glutationa, bem como por alterações histopatológicas avaliadas no ápice do ventrículo esquerdo. Avaliou-se ainda a mortalidade, os níveis de hemoglobina, contagem de leucócitos e neutrófilos e níveis de marcadores da função renal. O pré-tratamento com o óleo essencial de Alpinia zerumbet apresentou efeitos protetores no infarto do miocárdio induzido por isoproterenol em ratos, uma vez: atenuou as elevações de TGO e troponina I; atenuou a elevação do número de neutrófilos; preservou os níveis de catalase no miocárdio e preservou os níveis de glutationa no miocárdio. No entanto, não exerceu efeitos sobre: mortalidade, variação do peso dos animais; níveis séricos de TGP; níveis séricos de hemoglobina e contagem de leucócitos; níveis séricos de marcadores da função renal; alterações histopatológicas no ápice do ventrículo esquerdo. Os prováveis mecanismos de ação responsáveis pelos efeitos benéficos deste óleo em reduzir o grau de injúria miocárdica neste modelo experimental podem estar relacionados a propriedades antioxidantes e em aumento dos níveis de óxido nítrico.
6

Preconditioning with ternatina on myocardial infarction induced by isoproterenol in rats / PrÃ-condicionamento com ternatina no infarto do miocÃrdio induzido por isoproterenol em ratos

Carmelo Silveira Carneiro LeÃo Filho 14 September 2011 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Acute myocardial infarction (AMI) is one of the most common causes of death in our country. As population ages, such illness have its prevalence rates increased. In order to analyse drug effects over myocardial lesions as a result of AMI, the myocardial infarction induction model by means of the administration of isoproterenol in rats is one of the most used at all, given the capability of that substance of mimicking the myocardial injury observed in humans. In the present study, preconditioning with intra-peritoneal ternatin, at a dose of 1 mg/kg was used. Fourteen consecutive days were assessed in the isoproterenol-induced MI (120 mg/kg) in Wistar rats. Myocardial lesions induced by isoproterenol was indicated by the rise in biochemical markers levels, such as SGOT (serum glutamic oxaloacetic transaminase) and troponin I, reduction in the activity of catalase enzyme in the myocardial tissue, as well as by histopathological changes assessed in the apex of the left ventricle. It was also evaluated mortality rates, hemoglobin and SGPT (serum glutamic pyruvic transaminase) serum concentrations, leukocytes, neutrophils counts and renal function. Preconditioning with ternatin unveiled protective effects within the myocardial infarction induced by isoproterenol in rats, once it diminished mortality rates, attenuated SGOT and troponin I concentrations, preserved catalase levels in the myocardium and diminished histopathological changes in the apex of the left ventricle Possible pathways accountable for such good results, reducing the degree of myocardial injury in this experimental essay, might be related to the antioxidant properties attributable to ternatin. / O infarto agudo do miocÃrdio (IAM) à uma das principais causas de morte em nosso paÃs. Com o envelhecimento da populaÃÃo a tendÃncia à que se aumente a incidÃncia desta afecÃÃo. Para se estudar efeitos de drogas sobre a lesÃo miocÃrdica decorrente de IAM, um dos modelos experimentais mais utilizados à a induÃÃo de infarto do mocÃrdio (IM) com administraÃÃo de isoproterenol em ratos, uma vez que esta substÃncia causa uma lesÃo miocÃrdica semelhante à observada em IAM nos humanos. Nesse estudo o prÃ-condicionamento com ternatina administrada por via intraperitoneal, na dose de 1 mg/kg do animal, por catorze dias consecutivos, foi avaliado no IM induzido por isoproterenol (120 mg/kg do animal) em ratos Wistar. A lesÃo miocÃrdica induzida pelo isoproterenol foi indicada pela elevaÃÃo de marcadores bioquÃmicos, como transaminase glutÃmico-oxalacÃtica (TGO) e troponina I, reduÃÃo da atividade da enzima catalase no tecido miocÃrdico, bem como por alteraÃÃes histopatolÃgicas avaliadas na regiÃo do Ãpice do ventrÃculo esquerdo. Avaliou-se ainda a mortalidade, as concentraÃÃes sÃricas de transaminase glutÃmico-pirÃvica (TGP), hemoglobina, contagem de leucÃcitos e neutrÃfilos e marcadores da funÃÃo renal. O prÃ-tratamento com ternatina apresentou efeitos protetores no infarto do miocÃrdio induzido por isoproterenol em ratos, uma vez que dimunuiu a taxa de mortalidade, atenuou as elevaÃÃes de TGO e troponina I; preservou a atividade da enzima catalase e reduziu o grau de alteraÃÃes histopatolÃgicas. PossÃveis mecanismos de aÃÃo responsÃveis pelos efeitos benÃficos em reduzir o grau de lesÃo miocÃrdica neste modelo experimental podem estar relacionados a propriedades antioxidantes da ternatina.
7

The Role of PRAJA2 in TSH- or Isoproterenol- Stimulated Lipolysis in Human Adipocytes

McBride, Arran January 2014 (has links)
Thyrotropin (TSH) binds to TSH receptors on thyrocytes to regulate development and growth of the thyroid gland, and to stimulate thyroid hormone production. Thyrotropin has also been shown to act in an extra-thyroidal fashion, and to engage TSH receptors on adipocytes to induce lipolysis, similar to the response seen by stimulation with β-adrenergic receptor agonists (i.e. isoproterenol). In both cell types, cAMP-dependent kinase (PKA) is activated. Recently, PRAJA2, a novel AKAP and E3 ubiquitin ligase that targets the regulatory subunits of PKA was identified. The ubiquitin-dependent proteasomal degradation of the PKA regulatory subunits, due to PKA- phosphorylated PRAJA2, prolongs the catalytic activity of PKA, as shown in neuroblastoma cells by Lignitto et al., 2011. In adipocytes, stimulated PKA activity is required for lipolysis. Additionally, PRAJA2 has been described to have increased expression in TSH-responsive, differentiated thyroid cancer cells when compared to anaplastic thyroid tumor (Cantara et al., 2012) The aim of this study was to characterize PRAJA2 and its potential influence on adipocyte lipolysis. These data confirm that TSH and isoproterenol stimulate lipolysis in primary human differentiated adipocytes. PRAJA2 is expressed at the mRNA and protein level in differentiated adipocytes, with no change following stimulation with TSH or isoproterenol. Stimulation with isoproterenol, but not TSH, increases PKA-dependent phosphorylation of a 122kDa (potentially PRAJA2) and 69kDa protein identified in PRAJA2 immunoprecipitates. These proteins may prove important for lipolytic signaling or other PRAJA2-dependent process in adipocytes. Experimentation was unable to identify interactions between PRAJA2 and PKAR2 in differentiated adipocytes; however further investigations are required before discounting this interaction. An attempt was made to knockdown PRAJA2 in this model, and measure effects on lipolytic response; however, this was unsuccessful. Taken together, PRAJA2 appears to be phosphorylated following β-adrenergic stimulation in human adipocytes; however, further studies are needed to delineate the specific role of PRAJA2 in this human differentiated adipocyte model.
8

Exercise training, indomethacin, and isoproterenol-induced myocardial necrosis /

Brodowicz, Gary Ray January 1986 (has links)
No description available.
9

PrÃ-condicionamento com Ãleo essencial de Alpinia zerumbet no infarto do miocÃrdio induzido por isoproterenol em ratos / Preconditioning with essential oil of Alpinia zerumbet on myocardial infarction induced by isoproterenol in rats

Heraldo Guedes Lobo Filho 21 January 2011 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O infarto agudo do miocÃrdio (IAM), definido como a morte do mÃsculo cardÃaco decorrente de isquemia, à um dos diagnÃsticos mais comuns em pacientes hospitalizados nos paÃses industrializados. Para se estudar efeitos de drogas sobre a injÃria miocÃrdica decorrente de IAM, um dos modelos experimentais bastante utilizado à a induÃÃo de infarto do mocÃrdio (IM) com administraÃÃo de isoproterenol em ratos, uma vez que esta substÃncia causa uma lesÃo miocÃrdica semelhante a observada em IAM nos humanos. Nesse estudo o Ãleo essencial de Alpinia zerumbet, na dose de 100 mg/kg de peso, administrado por catroze dias consecutivos, foi avaliado no infarto do miocÃrdio induzido por isoproterenol (150 mg/kg de peso do animal) em ratos wistar. A injÃria miocÃrdica induzida pelo isoproterenol foi indicada pela elevaÃÃo de marcadores de injÃria miocÃrdica, como TGO e troponina I, reduÃÃo dos nÃveis de catalase e glutationa, bem como por alteraÃÃes histopatolÃgicas avaliadas no Ãpice do ventrÃculo esquerdo. Avaliou-se ainda a mortalidade, os nÃveis de hemoglobina, contagem de leucÃcitos e neutrÃfilos e nÃveis de marcadores da funÃÃo renal. O prÃ-tratamento com o Ãleo essencial de Alpinia zerumbet apresentou efeitos protetores no infarto do miocÃrdio induzido por isoproterenol em ratos, uma vez: atenuou as elevaÃÃes de TGO e troponina I; atenuou a elevaÃÃo do nÃmero de neutrÃfilos; preservou os nÃveis de catalase no miocÃrdio e preservou os nÃveis de glutationa no miocÃrdio. No entanto, nÃo exerceu efeitos sobre: mortalidade, variaÃÃo do peso dos animais; nÃveis sÃricos de TGP; nÃveis sÃricos de hemoglobina e contagem de leucÃcitos; nÃveis sÃricos de marcadores da funÃÃo renal; alteraÃÃes histopatolÃgicas no Ãpice do ventrÃculo esquerdo. Os provÃveis mecanismos de aÃÃo responsÃveis pelos efeitos benÃficos deste Ãleo em reduzir o grau de injÃria miocÃrdica neste modelo experimental podem estar relacionados a propriedades antioxidantes e em aumento dos nÃveis de Ãxido nÃtrico. / O infarto agudo do miocÃrdio (IAM), definido como a morte do mÃsculo cardÃaco decorrente de isquemia, à um dos diagnÃsticos mais comuns em pacientes hospitalizados nos paÃses industrializados. Para se estudar efeitos de drogas sobre a injÃria miocÃrdica decorrente de IAM, um dos modelos experimentais bastante utilizado à a induÃÃo de infarto do mocÃrdio (IM) com administraÃÃo de isoproterenol em ratos, uma vez que esta substÃncia causa uma lesÃo miocÃrdica semelhante a observada em IAM nos humanos. Nesse estudo o Ãleo essencial de Alpinia zerumbet, na dose de 100 mg/kg de peso, administrado por catroze dias consecutivos, foi avaliado no infarto do miocÃrdio induzido por isoproterenol (150 mg/kg de peso do animal) em ratos wistar. A injÃria miocÃrdica induzida pelo isoproterenol foi indicada pela elevaÃÃo de marcadores de injÃria miocÃrdica, como TGO e troponina I, reduÃÃo dos nÃveis de catalase e glutationa, bem como por alteraÃÃes histopatolÃgicas avaliadas no Ãpice do ventrÃculo esquerdo. Avaliou-se ainda a mortalidade, os nÃveis de hemoglobina, contagem de leucÃcitos e neutrÃfilos e nÃveis de marcadores da funÃÃo renal. O prÃ-tratamento com o Ãleo essencial de Alpinia zerumbet apresentou efeitos protetores no infarto do miocÃrdio induzido por isoproterenol em ratos, uma vez: atenuou as elevaÃÃes de TGO e troponina I; atenuou a elevaÃÃo do nÃmero de neutrÃfilos; preservou os nÃveis de catalase no miocÃrdio e preservou os nÃveis de glutationa no miocÃrdio. No entanto, nÃo exerceu efeitos sobre: mortalidade, variaÃÃo do peso dos animais; nÃveis sÃricos de TGP; nÃveis sÃricos de hemoglobina e contagem de leucÃcitos; nÃveis sÃricos de marcadores da funÃÃo renal; alteraÃÃes histopatolÃgicas no Ãpice do ventrÃculo esquerdo. Os provÃveis mecanismos de aÃÃo responsÃveis pelos efeitos benÃficos deste Ãleo em reduzir o grau de injÃria miocÃrdica neste modelo experimental podem estar relacionados a propriedades antioxidantes e em aumento dos nÃveis de Ãxido nÃtrico. / O infarto agudo do miocÃrdio (IAM), definido como a morte do mÃsculo cardÃaco decorrente de isquemia, à um dos diagnÃsticos mais comuns em pacientes hospitalizados nos paÃses industrializados. Para se estudar efeitos de drogas sobre a injÃria miocÃrdica decorrente de IAM, um dos modelos experimentais bastante utilizado à a induÃÃo de infarto do mocÃrdio (IM) com administraÃÃo de isoproterenol em ratos, uma vez que esta substÃncia causa uma lesÃo miocÃrdica semelhante a observada em IAM nos humanos. Nesse estudo o Ãleo essencial de Alpinia zerumbet, na dose de 100 mg/kg de peso, administrado por catroze dias consecutivos, foi avaliado no infarto do miocÃrdio induzido por isoproterenol (150 mg/kg de peso do animal) em ratos wistar. A injÃria miocÃrdica induzida pelo isoproterenol foi indicada pela elevaÃÃo de marcadores de injÃria miocÃrdica, como TGO e troponina I, reduÃÃo dos nÃveis de catalase e glutationa, bem como por alteraÃÃes histopatolÃgicas avaliadas no Ãpice do ventrÃculo esquerdo. Avaliou-se ainda a mortalidade, os nÃveis de hemoglobina, contagem de leucÃcitos e neutrÃfilos e nÃveis de marcadores da funÃÃo renal. O prÃ-tratamento com o Ãleo essencial de Alpinia zerumbet apresentou efeitos protetores no infarto do miocÃrdio induzido por isoproterenol em ratos, uma vez: atenuou as elevaÃÃes de TGO e troponina I; atenuou a elevaÃÃo do nÃmero de neutrÃfilos; preservou os nÃveis de catalase no miocÃrdio e preservou os nÃveis de glutationa no miocÃrdio. No entanto, nÃo exerceu efeitos sobre: mortalidade, variaÃÃo do peso dos animais; nÃveis sÃricos de TGP; nÃveis sÃricos de hemoglobina e contagem de leucÃcitos; nÃveis sÃricos de marcadores da funÃÃo renal; alteraÃÃes histopatolÃgicas no Ãpice do ventrÃculo esquerdo. Os provÃveis mecanismos de aÃÃo responsÃveis pelos efeitos benÃficos deste Ãleo em reduzir o grau de injÃria miocÃrdica neste modelo experimental podem estar relacionados a propriedades antioxidantes e em aumento dos nÃveis de Ãxido nÃtrico. / Acute myocardial infarction (AMI), defined as death of the cardiac muscle after an ischemic process, is worldwide known for its frequent diagnosis within hospitalized patients in modern industrialized countries. Myocardial infarction induced by isoproterenol (ISO) in rats is a very useful assay to study the effect of drugs on myocardial injury as a result of AMI, once its administration is responsible for a post-infarction human-like myocardial lesion. In this study, essential oil of Alpinia zerumbet (EOAZ), at a dose of 100 mg / kg, administered for fourteen consecutive days, was assessed in myocardial infarction induced by ISO (150 mg / kg bodyweight) in Wistar rats. The myocardial injury induced by ISO was indicated by elevated markers of myocardial injury, such as AST and troponin I, reduced levels of catalase and glutathione, as well as histopathological changes evaluated at the apex of the left ventricle. It was also evaluated mortality, hemoglobin levels, leukocyte and neutrophil counts and levels of markers of renal function. Pretreatment with the EOAZ showed protective effects on myocardial infarction induced by isoproterenol in rats, as attenuated the elevation of AST, Troponin I, attenuated the increased number of neutrophils; preserved the levels of catalase in the myocardium and preserved glutathione levels in the myocardium. However, do not exert any effects on mortality, weight variation of animals, serum ALT, serum levels of hemoglobin and white blood cell count, serum markers of renal function, histopathological changes in left ventricular apex. The probable mechanisms of action responsible for the beneficial effects of this oil in reduce the degree of myocardial injury in this experimental model may be related to antioxidant properties and increased levels of nitric oxide. / Acute myocardial infarction (AMI), defined as death of the cardiac muscle after an ischemic process, is worldwide known for its frequent diagnosis within hospitalized patients in modern industrialized countries. Myocardial infarction induced by isoproterenol (ISO) in rats is a very useful assay to study the effect of drugs on myocardial injury as a result of AMI, once its administration is responsible for a post-infarction human-like myocardial lesion. In this study, essential oil of Alpinia zerumbet (EOAZ), at a dose of 100 mg / kg, administered for fourteen consecutive days, was assessed in myocardial infarction induced by ISO (150 mg / kg bodyweight) in Wistar rats. The myocardial injury induced by ISO was indicated by elevated markers of myocardial injury, such as AST and troponin I, reduced levels of catalase and glutathione, as well as histopathological changes evaluated at the apex of the left ventricle. It was also evaluated mortality, hemoglobin levels, leukocyte and neutrophil counts and levels of markers of renal function. Pretreatment with the EOAZ showed protective effects on myocardial infarction induced by isoproterenol in rats, as attenuated the elevation of AST, Troponin I, attenuated the increased number of neutrophils; preserved the levels of catalase in the myocardium and preserved glutathione levels in the myocardium. However, do not exert any effects on mortality, weight variation of animals, serum ALT, serum levels of hemoglobin and white blood cell count, serum markers of renal function, histopathological changes in left ventricular apex. The probable mechanisms of action responsible for the beneficial effects of this oil in reduce the degree of myocardial injury in this experimental model may be related to antioxidant properties and increased levels of nitric oxide. / Acute myocardial infarction (AMI), defined as death of the cardiac muscle after an ischemic process, is worldwide known for its frequent diagnosis within hospitalized patients in modern industrialized countries. Myocardial infarction induced by isoproterenol (ISO) in rats is a very useful assay to study the effect of drugs on myocardial injury as a result of AMI, once its administration is responsible for a post-infarction human-like myocardial lesion. In this study, essential oil of Alpinia zerumbet (EOAZ), at a dose of 100 mg / kg, administered for fourteen consecutive days, was assessed in myocardial infarction induced by ISO (150 mg / kg bodyweight) in Wistar rats. The myocardial injury induced by ISO was indicated by elevated markers of myocardial injury, such as AST and troponin I, reduced levels of catalase and glutathione, as well as histopathological changes evaluated at the apex of the left ventricle. It was also evaluated mortality, hemoglobin levels, leukocyte and neutrophil counts and levels of markers of renal function. Pretreatment with the EOAZ showed protective effects on myocardial infarction induced by isoproterenol in rats, as attenuated the elevation of AST, Troponin I, attenuated the increased number of neutrophils; preserved the levels of catalase in the myocardium and preserved glutathione levels in the myocardium. However, do not exert any effects on mortality, weight variation of animals, serum ALT, serum levels of hemoglobin and white blood cell count, serum markers of renal function, histopathological changes in left ventricular apex. The probable mechanisms of action responsible for the beneficial effects of this oil in reduce the degree of myocardial injury in this experimental model may be related to antioxidant properties and increased levels of nitric oxide.
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La activación de proteína kinasa A disminuye la adhesión, migración y expresión de colágeno en fibroblastos y miofibroblastos cardíacos de rata neonata

Muñoz Rodríguez, Claudia Muriel January 2012 (has links)
Memoria para optar al título de Químico Farmacéutico / El corazón está compuesto por varios tipos celulares, de los cuales aproximadamente el 90% corresponde a cardiomiocitos y a fibroblastos. Los fibroblastos representan 2/3 de la población total de células del corazón y están encargados principalmente del recambio de las proteínas de la matriz extracelular. Este tipo celular puede responder frente a una variedad de citoquinas, factores de crecimiento y expresan sus receptores, indicativo de una respuesta autocrina. Por acción del TGF-β1 se diferencian a un fenotipo celular altamente secretor de colágeno, el miofibroblasto, principal célula encargada del proceso de cicatrización. Por otra parte, existen antecedentes que demuestran que en fibroblastos cardíacos la activación de las vías transduccionales que conducen a un aumento en los niveles de AMPc contribuye a disminuir el grado de fibrosis cardíaca, por regulación de procesos tales como adhesión, migración y la diferenciación a miofibroblasto. Para estos efectos, el AMPc es crítico debido al rol que juegan dos proteínas que se activan cuando aumentan los niveles de éste; estas son Epac (Exchange protein activated by cAMP/ proteína intercambiadora de nucleótidos de guanina activada por AMPc) y PKA (proteína quinasa A). Anteriormente se estudió el rol desempeñando por la Epac en los procesos de adhesión y migración de fibroblastos y miofibroblastos, en donde se vio que Epac aumenta la adhesión en ambos fenotipos celulares, y con respecto a migración, se vio que los estímulos que aumentan los niveles de AMPc aumentan la migración en fibroblastos, pero no así en miofibroblastos. Con esto surge la interrogante de saber cómo modula la PKA estos procesos. El objetivo de este trabajo fue determinar el rol que juega la PKA en adhesión, migración y expresión de colágeno. Se utilizaron estímulos que aumentan los niveles de AMPc (isoproterenol y forskolina), el agonista de la PKA 6-Bz-AMPc y su inhibidor H-89. Nuestros resultados mostraron que tanto en fibroblastos como en miofibroblastos, hubo un aumento de la adhesión al estimular con isoproterenol y forskolina, pero con 6-Bz-AMPc no se observó un cambio significativo con respecto al control, aunque sí tendió a disminuir lo que indica que la PKA no regula la adhesión celular. En migración no se observa efecto alguno con el agonista de la PKA y en la expresión de colágeno se vio una disminución con isoproterenol, forskolina, 6-Bz-AMPc y Me-AMPc tanto en fibroblastos como en miofibroblastos. Conclusión: PKA no interviene dentro de los procesos de adhesión y migración, pero sí lo hace en la expresión de colágeno. / The heart is composed by many types of cells, mainly cardiomyocytes and fibroblasts (almost 90% of total cells). Fibroblasts represent two thirds of the whole heart cell population and are responsible for the constant turnover of extracellular matrix proteins. This kind of cells can respond to many cytokines, growth factors and express their receptors indicating an autocrine answer. By the action of TGF-β1, they can be differentiated into a new phenotype called myofibroblasts, highly secreting of collagen and main cell involved into the healing process. Otherwise, there are numerous reports indicating that in cardiac fibroblasts, activation of signal transduction pathways leading to increased cAMP levels contributes to the reduction of cardiac fibrosis by regulating profibrotic processes like adhesion, migration and myofibroblast differentiation. For these effects cAMP is critical due to the role played by two proteins whose activation depends on the increase in the cAMP levels. These proteins are Epac (Exchange protein activated by cAMP) and PKA (protein kinase A). Formerly it was studied the role played by Epac in adhesion and migration of fibroblasts and myofibroblasts. Epac increased cell adhesion in both phenotypes, and about migration, in fibroblasts this phenomenon was increased with all the stimuli that increased the cAMP levels, whereas in myofibroblasts were no effect. So, we can ask about the role lead by PKA in these processes. The objective in this work was determined which role plays PKA in adhesion, migration and collagen expression. We used stimuli that increase cAMP levels (isoproterenol and forskolin), PKA’s agonist 6-ph-cAMP and its inhibitor H-89. Our results showed that both fibroblasts and in myofibroblasts there was an increase in cell adhesion in response to isoproterenol, forskolin and H-89, but with 6-ph-cAMP no significant change was observed respect control but tended to decrease, indicating that PKA is not involved in cell adhesion. In migration no effect was observed with 6-ph-cAMP, and finally in collagen expression these stimuli decreased the expression (we tried with Epac agonist Me-cAMP too) in both phenotypes. Conclusion: PKA does not intervene in adhesion and migration processes, but it does in collagen expression.

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