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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.
391

Análise de marcadores inflamatórios e antioxidantes após aplicação das técnicas de hipotermia tópica e pré-condicionamento isquêmico na lesão de isquemia e reperfusão hepática em ratos

Longo, Larisse January 2014 (has links)
Introdução: A hipotermia tópica (HT) e o pré-condicionamento isquêmico (PCI) são métodos utilizados para diminuir a lesão de isquemia/reperfusão (I/R). A eficácia do uso concomitante da HT e PCI (HT+PCI) no fígado em relação à inflamação e à citoproteção antioxidante não está elucidada. Objetivo: Avaliar o processo inflamatório e os mecanismos de segunda linha de defesa antioxidante na lesão de I/R hepática em ratos em relação à utilização das técnicas de HT e PCI de forma isolada ou associada. Métodos: Ratos Wistar (n=32) foram submetidos à isquemia hepática parcial (70%) durante 90 minutos seguida por 120 minutos de reperfusão. Os animais foram alocados nos grupos sham (n=4), isquemia normotérmica (IN, n=7), PCI (n=7), HT (n=7) e HT+PCI (n=7). O PCI consistiu na aplicação consecutiva de 10 minutos de isquemia e reperfusão antes do insulto isquêmico. A HT foi induzida pela superfusão de solução salina a 26°C sobre os lobos isquêmicos. A eutanásia foi realizada ao término do experimento e as amostras foram coletadas para a realização das análises moleculares utilizando as técnicas de ELISA e Western Blot, com o objetivo de comparar os perfis pró-inflamatório, anti-inflamatório e antioxidante. Resultados: O grupo HT comparado ao grupo IN apresentou diminuição da concentração do fator de necrose tumoral (TNF)-α, interleucina (IL)-1β, IL-6 e IL-12 e um aumento dos níveis de IL-10. O grupo HT apresentou menor expressão da óxido nítrico sintase induzível (iNOS) e um aumento da expressão da óxido nítrico sintase endotelial (eNOS). A expressão da NAD(P)H quinone oxidoreductase-1 (NQO1) foi menor no grupo HT. O PCI não demonstrou diferença significativa em relação a esses marcadores quando comparado ao grupo IN. O grupo HT+PCI apresentou menor concentração de IL-12 e menor expressão da iNOS e NQO1, mas em relação a estas moléculas a utilização de HT isolada demonstrou um comportamento semelhante. O grupo HT+PCI apresentou maior expressão da Kelch-like ECH-associated protein (Keap)-1 e menor expressão do nuclear erythroid 2-related factor 2 (Nrf2) nuclear e citoplasmático em relação ao grupo IN. Conclusão: O método de HT foi eficaz na proteção contra a lesão inicial de I/R. O uso de PCI isolado desencadeou a ativação da segunda linha de defesa antioxidante. A aplicação combinada de HT+PCI não confere benefício adicional em relação ao processo inflamatório quando comparado ao grupo HT, mas apresenta a vantagem de evitar a ativação da segunda linha de defesa antioxidante. / Background: Topical hypothermia (TH) and ischemic preconditioning (IPC) are used to decrease ischemia/reperfusion (I/R) injury. The effectiveness of using concomitantly TH and IPC (TH+IPC) in liver, regarding inflammation and antioxidant cytoprotection, is lacking. Aim: To evaluate the process inflammatory and second-line antioxidant defense mechanisms in hepatic I/R injury in rats in relation to the use of techniques TH and IPC isolate or associated. Methods: Wistar rats (n=32) subjected to partial (70%) hepatic ischemia during 90 minutes followed by 120 minutes of reperfusion. Livers from the animals allocated in sham (n=4), normothermic ischemia (NI, n=7), IPC (n=7), TH (n=7) and TH+IPC (n=7) groups. IPC consisted of consecutive 10-minute periods of ischemia and reperfusion before the ischemic insult. TH was induced by the superfusion of cooled saline at 26oC onto the ischemic lobes. Euthanasia was undertaken exactly at the end of the experiment and samples were collected for molecular analyses by ELISA and Western Blot assays, aiming to compare pro-inflammatory, anti-inflammatory and antioxidant profiles. Results: Compared with NI, TH presented decreased tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-12 concentrations and increased IL-10 levels. TH displayed lower inducible nitric oxide synthase (iNOS), higher endothelial nitric oxide synthase (eNOS) expressions. NAD(P)H-quinone oxidoreductase-1(NQO1) expression was also lower in TH. Isolate IPC showed no differences regarding all these markers compared to NI. TH+IPC showed decreased IL-12 concentration and reduced iNOS and NQO1 expressions, but regarding these molecules isolate TH behaved similarly. TH+IPC showed higher Kelch-like ECH-associated protein (Keap)-1 and diminished nuclear and cytosolic nuclear erythroid 2-related factor 2 (Nrf2) expressions than NI. Conclusion: TH was the effective method of protection against early I/R injury. Isolated IPC entailed triggering of second-line antioxidant defense enzymes. Combined TH+IPC seemed to confer no additional advantage over isolated TH in relation to the inflammatory process, but had the advantage of avoid activation second-line antioxidant defense enzymes.
392

Avaliação das variaveis metabolicas, hemodinamicas e sequestro de neutrofilos no rim de rato como efeitos da isquemia e reperfusão hepatica total apos choque hemorragico controlado com uso de diferentes soluções de reanimação / Evaluation of the metabolic, hemodynamic parameters and neutrophils sequestration in the kidney of rats resultanting from total hepatic ischemia and reperfusion after controlled hemorrhagic shock with use of different solutions to reanimation

Hirano, Elcio Shiyoiti, 1968- 23 February 2007 (has links)
Orientador: Mario Mantovani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-09T08:05:41Z (GMT). No. of bitstreams: 1 Hirano_ElcioShiyoiti_D.pdf: 1576822 bytes, checksum: a84a83fa8cd17ee274ad522665f99470 (MD5) Previous issue date: 2007 / Resumo: No Brasil, o trauma é uma das principais causas de mortalidade do adulto jovem e o choque hemorrágico é uma das situações críticas que está presente na maioria dos traumatizados graves. Dependendo da duração e intensidade, o choque hemorrágico torna-se responsável pela instalação da síndrome da resposta inflamatória sistêmica , ativando os neutrófilos que aderem ao endotélio e, por diapedese, seqüestram-se no interstício dos órgãos, onde iniciam a produção de radicais livres (O2-) estabelecendo lesão tecidual local. O objetivo deste estudo foi avaliar e comparar o seqüestro de neutrófilos no rim de rato, como efeito da isquemia e reperfusão hepática total após estado de choque hemorrágico controlado, com uso de diferentes soluções eletrolíticas. Utilizou-se 18 ratos Wistar, machos, adultos, divididos em três grupos conforme a solução utilizada para reanimação: Grupo SF: solução fisiológica; Grupo SH: solução hipertônica de NaCl a 7,5% seguido pela solução de Ringer com lactato; Grupo RL: solução de Ringer com lactato. Todos os animais foram submetidos à sangria controlada até a pressão arterial média (PAM) atingir 40 mmHg, permanecendo assim por 20 minutos. Realizou-se reanimação volêmica até PAM=80 mmHg com a solução conforme o grupo estudado. Em seguida realizou-se uma laparotomia e a manobra de Pringle por 15 minutos. Os animais foram acompanhados até duas horas. A eutanásia dos animais foi realizada com exsanguinação pelo cateter posicionado na artéria femoral esquerda. Os parâmetros hemodinâmicos e metabólicos foram avaliados para caracterização do estado de choque controlado: pressão arterial média, freqüência cardíaca, índice cardíaco, índice de resistência vascular sistêmica, pH, bicarbonato, reserva de base, lactato e eletrólitos. Para comparações estatísticas entre as contagens de neutrófilos, no interstício do córtex renal, foram efetuados os testes ANOVA e a análise de covariância, ajustando-se para o tempo de sobrevida. O volume de reanimação utilizado no tratamento do choque hemorrágico foi menor no GSH em comparação ao GRL, entretanto sem diferença estatística com GSF. O GSH apresentou maior nível de lactato em 60 minutos de reperfusão em relação ao GSF, entretanto sem diferença estatística com GRL. Os valores médios de tempo de sobrevida, em minutos, por grupo foram: Grupo SF: 79,0±12,0; Grupo RL: 97,0±11,0; Grupo SH: 67,0±10. Os valores médios da contagem de neutrófilos/campo no córtex renal foram: Grupo SF: 0,55±0,68; Grupo RL: 1,68±0,53; Grupo SH: 1,33±0,43. E, quando são ajustados para o tempo de sobrevida, encontraram-se: Grupo SF: 0,55; Grupo RL: 1,62; Grupo SH: 1,39. O GSF apresentou diferença estatística na contagem de neutrófilos com os demais, usando-se ou não o ajuste pelo tempo de sobrevida (p=0,016 e p=0,0128) / Abstract: In Brazil, the trauma is the main cause of death in young adults and hemorrhagic shock is one of the critical situations present in the major traumatism. Depending on duration and intensity, the hemorrhagic shock becomes responsible for the beginning of the systemic inflammatory response syndrome, activating neutrophils, which adhere to endothelium and for diapedesis sequestration on interstitium of the organs, where they initiate the production of free radicals (O2-), and promoting local lesion. The goal in this present study was to evaluate and compare neutrophils sequestration in the renal cortex of rats resultanting from total hepatic ischemia and reperfusion after controlled hemorrhagic shock, with use of different electrolytic solutions. Eighteen male adult rats Wista were divided into three equal groups according to the solution used to reanimation: Group PSS: physiologic saline solution; Group HSS: hypertonic saline hypertonic (7,5%) followed by lactated ringer¿s solution; Group LRS: lactated Ringer¿s solution. All animals were submitted to controlled bleeding maintaining mean arterial pressure (MAP) around 40 mmHg for 20 minutes. Volume infusion was performed to obtain and maintain a MAP=80 mmHg with the specific solution according to the studied group, followed by laparotomy and Pringle's maneuver for 15 minutes. The animals were observed until for two hours. The euthanasia of animals was perfomed by exsanguination via left femoral artery. The hemodynamic parameters were: MAP, heat rate, cardiac index, systemic vascular resistance index. The analyzed serum metabolic variables were: pH, bicarbonate, base deficit, lactato and electrolytes. For statistical comparisons between mean of neutrophils sequestration in interstitium of the renal cortex, One-way ANOVA and covariance analysis were used, adjusting itself for time of supervened. The mean total volume replacement for hemorrhagic shock was lesser in Group HSS than in Group LRS, and these values were not statiscally significant different from Group PSS. The Group HSS demonstrated greather lactate mean values at 60 minutes of reperfusion compared with Group PSS (p=NS in relation to Group LRS. The mean values of supervened, in minutes, for group were: Group PSS 79.0±12.0; Group 97,0±11,0; Group HSS 67.0±10. The mean values of neutrophils/field in the renal cortex : Group PSS 0.55±0.68; Group LRS 1.68±0.53; Group HSS 1.33±0.43. When adjusted for time of supervened: Group PSS 0.55; Group LRS 1.62; Group HSS 1.39. There was significant difference in neutrophils sequestration between Group PSS regarding the other groups, using itself or not the adjustment by time of supervened (p=0,016 and p=0,0128) / Doutorado / Cirurgia / Doutor em Cirurgia
393

Efeito do prÃ-tratamento com l-alanil glutamina e precondicionamento isquÃmico em modelo de isquemia / reperfusÃo de membros pÃlvicos em ratos. / Effect of the pre-treatment with l-alanyl glutamine and ischemic preconditioning in an ischemia / reperfusion model of hind limbs in rats

Emanuel Rocha Landim 09 December 2008 (has links)
No presente trabalho, estudaram-se os efeitos da l-alanil glutamina (Ala-Gln), do precondicionamento isquÃmico (PCI) e das duas tÃcnicas concomitantemente sobre a lesÃo pulmonar provocada por isquemia e reperfusÃo (I/R) causada por pinÃamento da aorta infra-renal em ratos. Foram utilizados 60 ratos machos Wistar, randomizados em cinco grupos (n = 12) divididos em dois tempos (n = 6): Grupo Simulado, Grupo I/R, Grupo PCI + I/R, Grupo Ala-Gln + I/R, Grupo Ala-Gln + PCI + I/R. Tempos: T1 (4h de isquemia) e T2 (4 horas de isquemia e 1h de reperfusÃo). Todos os grupos receberam soluÃÃo salina previamente, menos os grupos prÃ-tratados com Ala-Gln que receberam o dipeptÃdeo e soluÃÃo salina em igual volume. Foi utilizado o modelo de pinÃamento da aorta infra-renal com 4 horas de isquemia e 1 hora de reperfusÃo. Determinaram-se as concentraÃÃes de mieloperoxidase (MPO) pulmonar, substÃncias reativas ao Ãcido tiobarbitÃrico (TBARS) e glutationa reduzida (GSH) no sangue e pulmÃo para avaliar os grupos em estudo. O teste de Kolmogorov-Smirnoff mostrou distribuiÃÃo normal dos dados. Dados expressos como mÃdia acompanhada pelo seu desvio padrÃo (MÃdia  DPM) sendo realizado teste t de Student. Para anÃlise comparativa simultÃnea de trÃs grupos utilizou-se o teste Anova com pÃs-teste de Tukey. Em todos os casos foi adotado o nÃvel de significÃncia de p<0,05. Houve elevaÃÃo das concentraÃÃes de MPO pulmonar tanto no grupo submetido à isquemia quanto no grupo que realizou a I/R. Ocorreu reduÃÃo significante das concentraÃÃes de MPO pulmonar nos grupos submetidos à isquemia prÃ-tratados com Ala-Gln e com PCI. Na avaliaÃÃo dos grupos que sofreram I/R nÃo foi observada alteraÃÃo nas concentraÃÃes de MPO nos grupos prÃ-tratados Ala-Gln ou PCI. O grupo prÃ-tratado com as duas tÃcnicas apresentou aumento significante da MPO nos tempos estudados. A Ala-Gln como prÃ-tratamento isolado reduziu TBARS plasmÃtico na isquemia e o aumentou no pulmÃo na I/R. Jà no pulmÃo durante isquemia e no plasma na I/R houve reduÃÃo da GSH. O PCI como prÃ-tratamento isolado elevou o TBARS pulmonar na I/R e reduziu a GSH pulmonar na I/R. A associaÃÃo da Ala-Gln e PCI acresceu o TBARS plasmÃtico na isquemia, tambÃm o elevando no pulmÃo e mÃsculo na I/R. Jà a GSH, com os dois prÃ-tratamentos, sofre reduÃÃo plasmÃtica na isquemia e pulmonar na I/R, com elevaÃÃo plasmÃtica na I/R. O presente estudo demonstra que tanto o prÃ-tratamento com Ala-Gln como o PCI protegem contra a lesÃo isquÃmica à distÃncia, em modelo murino de pinÃamento da aorta infra-renal quando avaliado MPO pulmonar. O mesmo nÃo ocorre na lesÃo por I/R. NÃo hà benefÃcio, e sim agravamento de lesÃo à distÃncia pulmonar, na associaÃÃo dos dois prÃ-tratamentos ao mensurar a MPO pulmonar. / The present work determined the effects of pre-treatment with L-alanyl glutamine (Ala-Gln) and ischemic preconditioning (IPC), alone and in combination, against lesions caused by I/R by clamping the infrarenal aorta in rats. Sixty Wistar rats were distributed into five groups (n = 12) divided into two times (n = 6): Control, Group I/R, Group IPC + I/R, Group Ala-Gln + I/R, Group Ala-Gln + IPC + I/R. Times: T1 (infrarenal-aorta clamping ischemia-4h); T2 (ischemia-4h plus reperfusion-1h). Pulmonary myeloperoxidase (MPO) and plasma TBARS concentrations were measured. Data expressed as mean  standard-deviation, analyzed by Studentâs t-test and ANOVA/Tukeyâs post-test. P-values < 0,05 were considered significant. Increased MPO concentrations in ischemic group and in I/R group occurred as compared to control. Reduction in MPO concentrations happened in ischemic groups pre-treated with either Ala-Gln or IPC. I/R induced no change in MPO concentrations in groups pre-treated with either Ala-Gln or IPC. Pre-treating with the two procedures showed increased MPO at both times studied. Reduction in TBARS concentrations occurred in Ala-Gln pre-treated group, whereas significant elevation was observed when Ala-Gln and IPC were associated in ischemic animals. Ischemia/reperfusion induced elevation of plasma TBARS. Pre-treatment with either Ala-Gln or IPC protects against distant pulmonary lesion due to ischemia. The same did not occur in I/R lesion. Combining the two procedures aggravated inflammation indicated by increased MPO concentrations. Elevated TBARS concentrations in ischemic animals pre-treated with the two procedures indicate increased lipid peroxidation, whereas pre-treatment with Ala-Gln induced decreased TBARS concentrations.
394

PrÃ-condicionamento com l-alanil-glutamina na lesÃo aguda de isquemia e reperfusÃo cerebral em gerbils / Pre-conditioning on cerebral ischemia and reperfusion acute injury in gerbils with l-alanyl-glutemine

Vilma Leite Sousa Pires 20 December 2010 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Foram investigados os efeitos da L-alanil-glutamina (L-ALN-GLN) sobre as concentraÃÃes sanguÃneas e teciduais de metabÃlitos (lactato, piruvato, glicose e corpos cetÃnicos), substÃncias reagentes ao Ãcido tiobarbitÃrico (TBARS), glutationa (GSH), mieloperoxidase (MPO) e avaliaÃÃo histopatolÃgica em gerbils. Tratou-se de um estudo experimental, controlado. Utilizaram-se 54 gerbils, machos, com peso mÃdio de 150g, distribuÃdos aleatoriamente em 3 grupos: salina com isquemia e reperfusÃo (SIR), salina sem isquemia e reperfusÃo (SSI), L-alanil-glutamina com isquemia e reperfusÃo (GIR), redistribuÃdos em 3 subgrupos: T0 (tempo mÃximo de isquemia), T30 (30 min de reperfusÃo) e T60 (60 min de reperfusÃo), com 6 animais cada. Foram prÃ-tratados com soluÃÃo salina 2,0 mL 0,9% endovenoso (e.v.) ou L-ALNGLN 0,75g/Kg (e.v.), 30 min antes do inÃcio dos experimentos. A isquemia cerebral foi induzida pela oclusÃo bilateral das artÃrias carÃtidas comuns (ACCs), por um perÃodo de 15 minutos. ApÃs todos os procedimentos cirÃrgicos as amostras (sangue e tecido) foram coletadas ao final dos trÃs tempos. Nas comparaÃÃes entre os grupos (SSI) e (SIR) houve um aumento significante nas concentraÃÃes de lactato no sangue no grupo SIR em T0 (0,756Â0,091 versus 3,596Â1,546); p=0,0122, T30 (0,869Â0,254 versus 3,316Â1,356); p=0,0015 e em T60 (0,858Â0,460 versus 2,409Â0,801); p=0,0021. No tecido cerebral houve um aumento significante do lactato em T0 (1,374Â0,172 versus 2,530Â0,850); p=0,0085, T30 (0,891Â0,697 versus 1,840Â0,530); p=0,0243 e em T60 (1,182Â0,136 versus 1,744Â0,463); p=0,0173 no grupo SIR. Para as concentraÃÃes de piruvato no sangue observou-se um aumento significante em T0 (p=0,0424); T30 (p=0,0271) e em T60 (p=0,0175) e no tecido cerebral em T0 (p=0,0369) no grupo SIR. Para as concentraÃÃes de glicose no sangue houve um aumento significante em T0 (0,493Â0,393 versus 1,116Â0,364); p=0,0174, T30 (0,617Â0,356 versus 1,502Â0,314); p=0,0010 e em T60 (0,998Â0,411 versus 1,718 Â 0,477); p=0,0190 e no tecido cerebral em T0 (0,292Â0,081 versus 0,952Â0,7140); p=0,0484, T30 (0,264Â0,080 versus 1,038Â0,609); p=0,0116 e em T60 (0,234Â0,089 versus 0,985Â0,533); p=0,0067, no grupo SIR. Verificou-se um aumento significante nos nÃveis enzimÃticos de MPO em T0 (p<0,0001), T30 (p=0,0269) e em T60 (p=0,0005) no grupo SIR. Na avaliaÃÃo histopatolÃgica no grupo SIR nas camadas piramidal interna e granular interna foram observados aumento significante de picnose, neurÃnios vermelhos, congestÃo e edema, em T0, T30 e T60. Nas comparaÃÃes entre grupos (SIR) e (GIR) houve diminuiÃÃo significante no grupo GIR no sangue de lactato em T0 (3,596Â1,546 versus 1,960Â0,450); p=0,0321, T30 (3,316Â1,356 versus 1,971Â 0,568); p=0,0490 e em T60 (2,409Â0,801 versus 1,516Â0,307); p=0,0290 e no tecido cerebral em T0 (2,530Â0,850 versus 1,540Â0,302); p=0,0228. No tecido cerebral no grupo GIR houve diminuiÃÃo significante de TBARS em T30 (0,110Â0,006 versus 0,057Â0,040); p=0,0102 e um aumento significante de GSH em T0 (3,454Â1,584 versus 10,054Â2,880); p=0,0006, T30 (10,949Â1,579 versus 81,767Â9,060); p<0,0001 e em T60 (101,83Â2,631versus 114,924Â6,311); p=0,0011. Na avaliaÃÃo histopatolÃgica no grupo GIR na camada piramidal interna foram observados diminuiÃÃo significante de picnose nos tempos T30 (3,00 (2,75 a 4,25) versus 1,50 (0,75 a 2,00); p=0,0086 e em T60 (4,00 (3,75 a 5,55) versus 2,00 (1,75 a 4,00); p=0,0379 e nos neurÃnios vermelhos em T30 (3,00 (2,00 a 4,25) versus 1,50 (0,75 a 2,00); p=0,0159 e em T60 (4,00 (3,75 a 4,75) versus 2,00 (1,75 a 4,00); p=0,0493. Na camada granular interna no grupo GIR houve diminuiÃÃo significante de picnose em T30 (2,00 (1,00 a 3,25) versus 1,00 (0,00 a 1,00); p=0,0208 e em T60 1,50 (0,00 a 1,00) versus 0,00 (1,00 a 3,50); p= 0,0412, neurÃnios vermelhos em T30 (2,00 (1,00 a 3,25) versus 1,00 (0,00 a 1,00); p=0,0208 e em T60 1,50 (0,00 a 1,00) versus 0,00 (1,00 a 3,50); p=0,0412 e no grau de edema em T30 (2,00 (1,00 a 2,00) versus 1,00 (0,75 a 1,00); p=0,0225. Portanto, o prÃ-condicionamento com L-ALN-GLN foi capaz de induzir glicÃlise cerebral e de promover um efeito protetor na lesÃo de isquÃmia e reperfusÃo em gerbils, uma vez que elevou a sÃntese de glutationa tanto na isquemia quanto na reperfusÃo, reduziu a peroxidaÃÃo lipÃdica durante a fase de reperfusÃo e diminuiu o grau de edema intracerebral, a quantidade de picnose e neurÃnios vermelhos no tecido cerebral. / We investigated the metabolic effects of L-alanyl-Glutamine (L-ALN-GLN) on blood and tissue concentrations of metabolites (lactate, pyruvate, glucose and ketone bodies), thiobarbituric acid reactive substances (TBARS), glutathione (GSH), myeloperoxidase (MPO) and histopathologic evaluation of gerbils. This was an experimental and controlled study. Fifty-four male gerbils with a mean weight of 150gwere used, and were divided randomly and equally into 3 groups: saline with ischemia and reperfusion (SIR), saline without ischemia and reperfusion (SSI), L-alanyl-glutamine ischemia and reperfusion (GIR). They were then redistributed into three subgroups: T0 (maximum time of ischemia), T30 (30 min of reperfusion) and T60 (60 min of reperfusion), containing 6 animals each. They were pretreated with saline 2.0 mL 0.9% intra-venous (iv) or ALN-L-GLN 0.75 g / kg (iv) 30 min before the start of the experiments. Cerebral ischemia was induced by bilateral occlusion of the common carotid arteries (CCAs) for a period of 15 minutes. After all surgical procedures, the samples (blood and tissue) were collected at the end of the three periods. When comparing SSI and SIR groups, a significant increase of lactate was found in SIR group in T0 (0.756Â0.091 versus 3.596Â1.546; p=0.0122, T30 (0.869Â0.254 versus 3.316Â1.356); p=0.0015, and T60 (0.858Â0.460 versus 2.409Â0.801); (p=0.0122). In brain tissue there was significant lactate increase in TO (1.374Â0.172 versus 2.530Â0.850); p=0.0085, T30 (0.891Â0.697 versus 1.840Â0.530); p=0.0243 and T60 (1.182Â0.136 versus 1.744Â0.463); p=0.0173, in SIR group. In blood and tissue concentrations of pyruvate was found a significant increase in T0 (p=0.424), T30 (p=0.0271) and T60 (p=0.0175), and in brain tissue in T0 (p=0.0369) in the SIR group. In glucose blood concentrations there was a significant increase in T0 (0.493Â0.393 versus 1.116Â0.364); p=0.0174, T30 (0.617Â0.356 versus 1.502Â0.314); p=0.0010 and T60 (0.998Â0.411 versus 1.718Â0.477); p=0.0190, and in brain tissue in T0 (0.292Â0.081 versus 0.952Â0.7140); p=0.0484, T30 (0.264Â0.080 versus 1.038Â0.609); p=0.0116 and T60 (0.234Â0.089 versus 0.985Â0.533); p=0.0067, in the SIR group. On blood ketone bodies there was a significant increase in T0 (p=0.0006) and T60 (p=0.0455), and in brain tissue in T0 (p=0.0428) in SIR group. There was a significant increase in MPO enzyme levels at T0 (p<0.0001), T30 (p=0.0269) and T60 (p=0.0005). In the histopathological evaluation in the internal pyramidal and granular layers in group CRS observed a significant increase of pyknosis, red neurons, congestion and edema, at T0, T30 and T60. In the comparison between the (SIR) and (GIR) groups, there was a significant decrease in T0 (3.596Â1.546 versus 1.960Â0.450); p=0.0321, T30 (3.316Â1.356 versus 1.971Â0.568); p=0.0490 and T60 (2.409Â0.801 versus 1.516Â0.307); p=0.0290, and in brain tissue there was significant decrease in T0 (2,530Â0,850 versus 1.540Â0,302); p=0.0228. In brain tissue was found significant decrease in TBARS concentrations in T30 (0.110Â0.006 versus 0.057Â0.040); p=0.0102, and a significant increase of GSH in T0 (3.454Â1.584 versus 10.054Â2.880), p=0.0006, T30 (10.949Â1.579 versus 81.767Â9.060); p<0.0001 and T60 (101.83Â2.631 versus 114.924Â6.311); p=0.0011 in GIR group. Regarding the histological examination, a significant decrease of pyknosis was found at T30 (3.00 (2.75 to 4.25) versus 1.50 (0.75 to 2.00); p= 0.0086 and T60 (4.00 (3.75 to 5.55) versus 2.00 (1.75 to 4.00); p=0.0379 and red neurons at T30 (3,00 (2,00 to 4.25) versus 1.50 (0.75 to 2.00); p=0.0159 and T60 (4.00 (3.75 to 4.75) versus 2,00 (1.75 to 4.00); p= 0.0493. in the internal pyramidal layer. In the Internal granular layer in GIR group there was a significant reduction of pyknosis at T30 (2.00 (1.00 to 3.25) versus 1.00 (0.00 to 1.00); p=0.0208 and T60 1.50 (0.00 to 1.00) versus 0.00 (1.00 to 3.50); p=0.0412, red neurons in T30 (2.00 (1.00 to 3.25) versus 1.00 (0.00 to 1.00); p=0.0208 and T60 1.50 (0.00 to 1.00) versus 0.00 (1.00 to 3.50); p=0.0412 and on the intracerebral edema level at T30 (2.00 (1.00 to 2.00) versus 1.00 (0.75 to 1.00); p=0.0225. Therefore, the preconditioning with L-GLN-ALN is able to induce brain glicolise and promote a protective effect on ischemic brain injury and reperfusion in gerbils, since it increased the glutathione synthesis both on ischemia and reperfusion, as well as decreasing lipid peroxidation during the reperfusion phase and decreased the intercerebral edema level, and the number of pyknosys and red neurons in brain tissue.
395

Intervenção farmacológica na lesão renal aguda isquêmica em ratos: resposta funcional e histológica tempo dependente / Pharmacological intervention in ischemic acute kidney injury in rats: functional and histological time dependent protection

Mirian Watanabe 31 January 2011 (has links)
A gravidade da síndrome isquemia/reperfusão determina o prognóstico da lesão renal aguda (LRA). Agentes como o citrato de sildenafil (Sil) e a N-acetilcisteína (NAC) tem demonstrado efeito renoprotetor na LRA isquêmica com resultados ainda inconclusivos. Esse estudo investigou o efeito do Sil e da NAC na LRA com diferentes tempos de isquemia. Foram utilizados grupos de ratos Wistar, adultos e machos: SHAM; Isquemia 30 min (clampeamento dos pedículos renais por 30 min); Isquemia 30 + Sil (Sil 0,25 mg/kg 60 min antes da isquemia renal); Isquemia 30 + NAC (NAC 150 mg/kg antes e após a isquemia renal); Isquemia 45 (clampeamento dos pedículos renais por 45 min); Isquemia 45 + Sil e Isquemia 45 + NAC. Foram avaliadas a função renal (clearance de creatinina e fração de excreção de sódio-FENa); a lesão oxidativa (peróxidos urinários; substâncias reativas ao ácido tiobarbitúrico - TBARS; óxido nítrico - NO e tióis no tecido renal); a síntese protéica da óxido nítrico sintase induzível iNOS e da heme oxigenase-1 HO-1 (western blotting) e análise histológica renal (área intersticial relativa - AIR e lesão tubulointersticial). Os grupos 30 min tratados com Sil e NAC demonstraram melhora da função renal, redução dos índices oxidantes e NO, ausência de iNOS e presença de HO-1. Nos grupos 45 min, o Sil manteve a função renal, porém demonstrou proteção tubular e oxidante; a NAC não demonstrou efeito protetor em nenhum dos parâmetros avaliados. Quanto à histologia, apenas o Sil induziu redução da AIR e da lesão tubulointersticial nos tempos 30 e 45 min. O estudo confirmou que as características funcionais e histológicas induzidas pelo tempo de isquemia na LRA determinam as respostas às manobras farmacológicas de prevenção. A expressão HO-1 pode ser considerada um mediador de proteção renal. / Severity of ischemic/reperfusion injury syndrome determines the prognosis of acute kidney injury (AKI). Agents such as sildenafil citrate (Sil) and N-acetylcysteine (NAC) have demonstrated renoprotective effect on ischemic AKI which data is still inconclusive. This study investigated the protective action of Sil and NAC in the AKI with different time of ischemia. Adult, male, Wistar rats were divided: SHAM, Ischemia 30 min (renal pedicles clamping for 30 min), Ischemia 30 + Sil (Sil 0,25 mg/kg 60 min before renal ischemia), Ischemia 30 + NAC (NAC 150 mg/kg before and after renal ischemia), Ischemia 45 min (renal pedicles clamping for 45 min), Ischemia 45 + Sil, Ischemia 45 + NAC. Renal function (creatinine clearance and urine sodium fractional excretion - FENa); oxidative injury (urinary peroxides, thiobarbituric acid reactive substances - TBARS, nitric oxide - NO and thiols in renal tissue); expression of inducible nitric oxide synthase - iNOS and heme oxygenase-1 HO-1 (western blotting) and kidney histological analysis (fractional interstitial area - FIA and tubuleinterstitial injury) were evaluated. Sil and NAC treatment in 30 min renal ischemia induced increase in renal function, decrease in the rate of oxidation and NO levels, iNOS absence and HO-1 expression. In the Ischemia 45 groups, Sil it maintained renal function, however demonstrated tubular and oxidative protection; NAC produced no renoprotective effect on any of the parameters evaluated. Histology studies showed that, only Sil induced reduction in FIA and tubuleinterstitial injury at 30 and 45 min ischemic time. The study confirmed that the functional and histological characteristics induced by time of ischemia determine the renoprotective pharmacological agent action in the AKI. HO-1 expression can be a renal protection mediator.
396

Efeito da pentoxifilina e da solução salina hipertônica na isquemia/reperfusão intestinal e suas consequências no pulmão: estudo experimental em ratos / The effect of pentoxifylline and hypertonic saline in intestinal ischemia / reperfusion and their consequences in the lung: an experimental study in rats

Geraldo Magela Nogueira Marques 19 September 2012 (has links)
Isquemia e reperfusão (I/R) de vasos mesentéricos que acarretam insuficiência vascular aguda são acompanhadas de insuficiência em múltiplos órgãos e estão associados a altas morbidade e mortalidade. Os benefícios da solução hipertônica e da pentoxifilina foram testados isoladamente e em conjunto para melhorar o fluxo sanguíneo e o estado de oxigenação dos tecidos com redução da reação inflamatória e de apoptose, tanto no intestino quanto no pulmão enquanto órgão alvo. Foram utilizados 24 ratos Wistar machos pesando entre 200 e 250g distribuídos em 4 grupos (n=6). Foram submetidos à laparotomia e período de isquemia por clampeamento dos vasos mesentéricos por 40 minutos. O período de reperfusão foi de 80 minutos. A cada 40 minutos foram realizadas coletas de sangue arterial para gasometria. Os animais foram alocados nos grupos: grupo I/R (IR) onde I/R foi realizada e os animais receberam 4ml/kg de solução salina isotônica. O grupo solução salina hipertônica (SH) recebeu 4ml/kg de solução hipertônica a 7,5% e o grupo pentoxifilina (PTX) recebeu 30mg/kg de pentoxifilina diluída em NaCl 0,9% em um volume total de 4ml/kg ao final da isquemia intestinal. O grupo solução salina hipertônica+pentoxifilina (SH+PTX) recebeu ambas as soluções com volume total de 4m/kg no mesmo momento. As biopsias de intestino e pulmão foram colhidas ao final do experimento e foram submetidas à coloração em HE e à imuno-histoquímica para COX 2, caspase-3 clivada e Bcl-2. Os valores de sO2 revelaram diferença estatisticamente significante aos 40 (p=0,0099) e 80 (p=0,0074) minutos de reperfusão na comparação do grupo IR com os grupos SH e SH+PTX. Os valores de lactato foram estatisticamente significantes aos 40 minutos (p=0,0069) e 80 minutos (p=0,0098) de reperfusão, entre os grupos IR e os grupos SH e SH+PTX. A avaliação histológica em HE no tecido intestinal evidenciou diferença estatisticamente significantes na comparação dos grupos SH (p=0,0200), PTX (p=0,0200) e HS+PTX (p=0,0412) com o grupo IR, assim como no tecido pulmonar, que evidenciou diferenças estatisticamente significantes na comparação de IR com SH (p=0,006), PTX (p=0,0433) e SH+PTX (p=0,0040). A marcação citoplasmática de COX 2 revelou diferença estatisticamente significante ao comparar o grupo IR com o grupo SH+PTX (p=0,0015), Na avaliação do tecido pulmonar foi observado o grupo IR estabelecendo diferenças estatisticamente significantes na comparação com os grupos SH (p=0,0455), PTX (0,0143) e SH+PTX (p=0,0455). A avaliação de apoptose por imunohistoquímica para caspase 3 clivada evidenciou diferença com significância estatística ente os grupos IR e SH (p=0,0085) e os grupos PTX e SH (p=0,0120) em tecido intestinal. Em tecido pulmonar, entre IR e PTX (p=0,0090) e SH e PTX (p=0.0412). A marcação citoplasmática de Bcl-2 evidenciou que somente entres os grupos IR e SH+PTX (p=0,0012) se estabeleceu significância estatística em tecido intestinal No pulmão a diferença foi evidenciada em relação ao grupo IR e os grupos SH (p=0,0128), PTX (p=0,0085) e SH+PTX (p=0,0066). Conclui-se que o uso associado de pentoxifilina e solução salina hipertônica oferece os melhores resultados dos pontos de vista metabólico, inflamatório e da inibição da apoptose / Ischemia-reperfusion (I/R) of the mesenteric vessels cause acute vascular insufficiency and is followed by multiple organs failure and high morbidity and mortality. The benefits of hypertonic saline (NaCl 7,5%) and pentoxifylline were tested to improve metabolic and oxygen status of tissues with reduced inflammatory reaction and apoptosis, both in the gut as in the lung as target organ. 24 male Wistar rats weighing 200 to 250g. They underwent laparotomy and ischemia by clamping the mesenteric vessels for 40 minutes. The reperfusion period was 80-minute long. Every 40 minutes, blood was collected for arterial gas analysis. The animals were set into 4 groups (n=6): I/R (IR) received isotonic saline just before reperfusion (4ml/kg). Hypertonic saline group (HS) received 7.5% hypertonic saline solution (4ml/kg) and Pentoxifylline group (PTX) received pentoxifylline (30mg/kg)diluted in NaCl 0.9% at the end of the mesenteric ischemia. Hypertonic saline+pentoxifylline group (SH-PTX) received both solutions at the same doses. Biopsies of intestine and lung were collected at the end of the experiment and were subjected to HE staining and immunohistochemistry staining to COX 2, cleaved caspase-3 and Bcl-2. About the values of sO2, a statistically significant difference was established when groups were compared at 40 (p=0.0099) minutes and 80 (p=0.0074) of reperfusion. The lactate values were statistically significant after 40 (p=0.0069) and 80 (p=0.098) minutes of reperfusion as well. Histological evaluation with HE revealed a statistically significant difference in the comparison of SH (p=0.0200), PTX (p=0.0200) and HS + PTX (p=0.0412) groups compared to IR group in intestine tissue and SH (p=0.0006), PTX (p=0.0433) and HS + PTX (p=0.040) in lung tissue. Cytoplasmic staining of COX 2 revealed a statistically significant difference when comparing IR (p=0.0015) to HS+PTX in intestinal tissue. The evaluation of the lung tissue for COX 2 showed IR group setting statistically significance when compared to HS 9p=0,045), PTX (0.0143) and HS+PTX (p=0.0455) groups. The evaluation of apoptosis by immunohistochemistry for cleaved caspase 3 revealed that there was a significant difference between IR versus SH (p=0.0085) and PTX versus HS (p= 0.0120) in intestinal tissue and IR versus PTX (p=0,0090) and PTX versus SH (p=0.0412) in lung tissue. The cytoplasmic Bcl-2 expression shows that only between groups IR versus HS+PTX (p = 0.0012) statistical significance was established in intestinal tissue. Lung tissue showed the difference was evidenced in relation to IR versus SH (p=0.0128), PTX (p=0.0085) and HS+PTX (p=0.0066). It may be concluded that the combined use of pentoxifylline and hypertonic saline offers best results on metabolic, inflammatory and apoptosis inhibitory aspects
397

Efeitos da N-acetilcisteína na resposta inflamatória e na translocação bacteriana em modelo de obstrução e isquemia intestinal em ratos / Evaluate the effect of N-acetylcysteine in the inflammatory response and the translocation in an experimental model of intestinal obstruction and ischemia

Rafael Izar Domingues da Costa 26 September 2017 (has links)
A obstrução intestinal mecânica representa uma condição de urgência, necessitando diagnóstico precoce e terapêutica adequada, em virtude do seu elevado grau de morbidade e de mortalidade. Desta forma, o objetivo deste estudo foi avaliar o efeito da N-acetilcisteína associada ao Ringer lactato ou à solução salina hipertônica na resposta inflamatória, histologia e translocação bacteriana em modelo experimental de obstrução e isquemia intestinal. Para tanto, Foram constituídos quatro grupos experimentais, com 10 ratos Wistar em cada, além do grupo de referência: OI - Submetidos a obstrução e isquemia intestinal e enterectomia com anastomose intestinal, sem reanimação volêmica; RL - Submetidos a obstrução e isquemia intestinal, reanimação volêmica com Ringer lactato (32ml/kg, i.v., em 10 minutos) e enterectomia com anastomose intestinal; RLNAC - Submetidos a obstrução e isquemia intestinal, reanimação volêmica com Ringer lactato associado a NAC (32ml/kg + 150 mg/kg i.v. em 10 minutos) e enterectomia com anastomose intestinal; SHNAC - Submetidos a obstrução e isquemia intestinal, reanimação volêmica com solução salina hipertônica a 7,5% associado com NAC (4ml/kg + 150 mg/kg i.v., em 10 minutos) e enterectomia com anastomose intestinal. Grupo Referência (n=5): Animais anestesiados, submetidos a coleta de materiais para cultura e histologia e sacrificados por exsanguinação. Os animais receberam uma associação anestésica de cetamina e xilazina intramuscular em membro posterior direito, na dose de 60mg/kg e 10mg/kg, respectivamente. Decorridas 24 h do tratamento, a eutanásia foi realizada por exanguinação, sob anestesia, após a coleta dos tecidos / Mechanical intestinal obstruction represents a condition of urgency, necessary early diagnosis and appropriate therapy, due to their high degree of morbidity and mortality. In this way, the objective of this study was to evaluate the effect of N-acetylcysteine associated with lactated Ringer\'s or hypertonic saline solution in the inflammatory response, histology and translocation in an experimental model of intestinal obstruction and ischemia. For Four experimental groups were constituted with 10 Wistar rats each, in addition to the reference group: OI - submitted to obstruction and ischemia intestinal and enterectomy with intestinal anastomosis, without volume resuscitation; RL - Undergoing intestinal obstruction and ischemia, volume resuscitation with Ringer\'s lactate (32ml / kg, i.v., within 10 minutes) and anastomosis enterectomy intestinal; RLNAC - Undergoing obstruction and intestinal ischemia, resuscitation with lactated Ringer\'s lactating NAC (32 ml / kg + 150 mg / kg i.v. in 10 minutes) and enterectomy with intestinal anastomosis; SHNAC - Submitted to obstruction and intestinal ischemia, volume resuscitation with saline solution hypertension at 7.5% associated with CAP (4 ml / kg + 150 mg / kg i.v., in 10 minutes) and enterectomy with intestinal anastomosis. Reference Group (n = 5): Anesthetized animals, submitted to collection of materials for culture and histology and sacrificed by exsanguination. The animals received a anesthetic association of ketamine and intramuscular xylazine in limb posterior right, at the dose of 60mg / kg and 10mg / kg, respectively. After 24 h of treatment, euthanasia was performed by exsanguination, under anesthesia, after collection of tissues
398

Biochemical and reperfusion targeting strategies to improve brain protection during prolonged hypothermic circulatory arrest

Rimpiläinen, J. (Jussi) 23 January 2001 (has links)
Abstract Ischaemic cerebral injury follows a well attested sequence of events including three phases, i.e. depolarization, biochemical cascade and reperfusion injury. Glutamate excitotoxicity plays an important role in the development of ischaemic brain injury following prolonged hypothermic circulatory arrest (HCA), and leukocyte infiltration and a cytokine-mediated inflammatory reaction are known to play a pivotal role in the reperfusion phase. The aim of this series of experimental studies was to develop biochemical and reperfusion-related strategies to improve brain protection. We tested the hypotheses that the Na+ channel blocker lamotrigine (I) or the N-Methyl-D-Aspartate-receptor antagonist memantine (III) could improve the cerebral outcome after HCA and studied whether a leukocyte-depletion filter (L-DF; LeukoGuard LG6®, Pall Biomedical, Portsmouth, U.K) could mitigate brain injury (II). The aim of the fourth study was to find out whether lamotrigine combined with the leukocyte-depleting filter can potentiate cerebral protection (IV). A chronic porcine model was used, in which haemodynamic, electrophysiological, metabolic and temperature monitoring were performed for four hours after the instigation of rewarming and S-100β measured up to 20 hours. Cytokines were measured, microdialysis was performed, and daily behavioural assessments were made until death or elective sacrifice on the seventh postoperative day, upon which a histopathological analysis of the brain was carried out. The rate of EEG burst recovery was higher in the lamotrigine-treated animals, the median being 40% of the baseline compared with 17% in the placebo group at 4 hours after the start of rewarming (p = 0.02) and 80% compared with 20% at 4 hours (p = 0.01). Complete behavioural recovery was seen in 5/8 of cases (63%) after lamotrigine administration, compared with 1/8 (13%) in the placebo group (p = 0.02). The median behavioural score among the animals that survived for 7 days was higher in the lamotrigine group (8) than in the controls (7) (p = 0.02). Mortality was 2/10 in the L-DF group and 5/10 in the controls, the median behavioural score on day 7 being higher in the L-DF group (8.5 vs. 3.5 p = 0.04). The median of the total histopathological score was 6.5 in the L-DF group and 15.5 in the control group (p = 0.005). In the memantine group 5/10 animals survived seven days, as compared with 9/10 in the placebo group, and the median behavioural score on day 7 was 3.5 compared with 7.5 in the placebo group (p = 0.39). The median of the total histopathological score was 16 in the memantine group and 14 in the placebo group (p = 0.25). In the LD-F + lamotrigine group 7/8 animals survived for seven days, as compared with 4/8 in the lamotrigine only group and 3/8 among the controls. EEG burst recovery 7 hours after the start of rewarming was highest in the LDF + lamotrigine group, the median being 94% (p = 0.024 vs. controls), compared with 81% in the lamotrigine group and 64% in the control group. The median behavioural score on day 7 was 9 in the LD-F + lamotrigine group (p = 0.004 vs. controls), 4 in the lamotrigine group and 0 in the control group, while the median of total histopathological score was 14 (p = 0.046 vs controls), 14.5 (p = 0.062 vs. controls) and 21, respectively. The control group had the highest intracerebral lactate, glutamate and glycerol levels after HCA. In conclusion, the results indicate that the NA+ channel blocker lamotrigine improves the neurological outcome after a prolonged period of HCA but that the NMDA receptor antagonist memantine does not have this property in the present setting. The leukocyte-depleting filter mitigates brain injury after a prolonged period of HCA, and lamotrigine can potentiate this effect.
399

Myocardial ischemia-reperfusion injury and systemic inflammatory response in high-risk cardiac surgery:a clinical study of the effects of high-dose glucose-insulin treatment and the use of leukocyte-depleting filter

Koskenkari, J. (Juha) 03 October 2006 (has links)
Abstract Cardiac surgery with cardiopulmonary bypass induces the activation of systemic inflammatory response syndrome (SIRS) and results in at least some degree of global myocardial ischemia. Although these responses are usually short-lived, they may lead to serious complications and organ system failures. The present study evaluated the effects of high-dose glucose-insulin (1IU/kg/h) treatment (GIK) administered with the hyperinsulinemic normoglycemic clamp technique and a leukocyte-depleting filter on markers of systemic inflammatory response and myocardial ischemia-reperfusion injury in certain cardiac surgical risk groups. The study involved four prospective randomized controlled clinical trials and 119 patients. Cardioprotective effects were measured as myocardial enzyme release, recovery of contractile function and incidence of arrhythmias in all studies. The hemodynamic and metabolic effects of high-dose glucose-insulin treatment were evaluated in patients admitted for combined aortic valve (AS) and coronary surgery (40) and for urgent coronary surgery (39), and the latter study also involved proinflammatory cytokine and C-reactive protein analyses. The impacts of leukocyte filter on the expression of neutrophil adhesion molecules along with proinflammatory cytokines were evaluated in patients admitted for combined aortic valve (AS) and coronary surgery (20) and for solitary coronary surgery (20). The high-dose glucose-insulin treatment was associated with better preserved myocardial contractile function and less need for inotropic support after combined aortic valve and coronary surgery (I) and attenuation of postoperative CRP release after urgent coronary surgery (II). No effects on postoperative myocardial enzyme release (I, II) or on proinflammatory cytokine responses (II) were detected. The number of hypoglycemic events was low. The use of a leukocyte filter throughout the cardiopulmonary bypass period increased the neutrophil adhesion molecule CD11b expression in patients with both normal and prolonged CPB times and was associated with an enhanced proinflammatory cytokine response (III, IV). In conclusion, high-dose glucose-insulin treatment is safe, but requires strict control of blood glucose level. It reduces the need for inotropic support in patients with compromised cardiac status. The use of leukocyte filter leads to increased leukocyte activation and proinflammatory reaction.
400

Investigation into the effects of specific muscarinic acetylcholine receptor antagonists on the myocardium in pre-clinical conditions of ischaemia reperfusion injury and oxidative stress model

Khan, J. January 2015 (has links)
Muscarinic acetylcholine receptors (mAChRs) are G-protein coupled receptors that mediate various actions of Acetylcholine (ACh) in the central nervous system and peripheral nervous system. In mammals, five distinct mAChR subtypes (M1-M5) have been recognised with the M2 subtype being predominantly present in the heart. The mAChR antagonists are routinely used for the treatment of various pathophysiological conditions including respiratory conditions. However, it has been postulated that mAChR antagonists may increase morbidity and mortality in chronic obstructive pulmonary disorder (COPD) and asthma patients with underlying cardiovascular disease, raising concerns regarding the cardiovascular safety of these agents. The current study was therefore undertaken to investigate the effects of individual mAChR antagonists in the setting of myocardial ischaemia reperfusion injury and oxidative stress models. We also investigated whether the inhibition of the mitochondrial permeability transition pore (MPTP) with cyclosporine-A (CsA) in the presence and absence of individual mAChR antagonists provided protection against ischaemia reperfusion injury. Furthermore, we also aimed to investigate the intracellular signalling pathway associated with mAChRs antagonists mediated myocardial injury under the stress conditions. Langendorff results showed that the non-selective M1-M3 mAChR antagonist, ipratropium bromide, the M2 mAChR antagonist, AF-DX 116 and the M3 mAChR antagonist, DAU 5884 significantly increased the infarct size to risk ratio of the heart in conditions of ischaemia and reperfusion. Detrimental effects of AF-DX 116 and DAU 5884 were abrogated by co-treatment of these drugs with mAChR agonist, acetylcholine (ACh) and/or CsA. Cell viability data of isolated cardiac myocytes revealed that AF-DX 116 and DAU 5884 caused a concentration dependent decrease in the viability of cardiac myocytes as well as causing a reduction in the time taken to depolarisation and hypercontracture under oxidative stress. AF-DX 116 and DAU 5884 significantly increased the levels of p-SAPK/JNK and decreased the levels of p-Akt and p-ERK. In addition, ACh and CsA showed to activate p-Akt and p-ERK. To conclude, the data suggest that AF-DX 116 and DAU 5884 caused cardiotoxicity at cellular, tissue and protein level in conditions of ischaemia reperfusion injury and oxidative stress. Furthermore, inhibition of the mitochondrial transition pore with CsA protected against the AF-DX 116 and DAU 5884 induced injury via activation of the pro-survival proteins, p-Akt and p-ERK.

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