The modulation of the electron transport during ischemia-reperfusion has been shown to be protective. We hypothesized that metformin, a Complex I inhibitor, may exhibit characteristics of a pharmacological agent that could achieve long-term therapeutic intervention against ischemia-reperfusion injury. Mitochondria were harvested from adult male mice and incubated with or without metformin at 30oC for 15 minutes, while being shaken at 300 rpm. Metformin decreased Complex I oxidative phosphorylation and Complex I activity. However, metformin also increased injury and decreased the maximum membrane potential. Even though there was a decrease in maximum membrane potential, the proton motive force (PMF) was still intact as the ADP/O ratio was not affected. In conclusion, metformin does exhibit some characteristics of a drug that could achieve long-term therapeutic benefit against ischemia-reperfusion.

Brief periods of skeletal muscle ischemia (ischemic pre-conditioning) alter cellular metabolism in a way that confers protection over subsequent ischemic episodes. The mechanisms behind this effect have been studied indirectly through assays for the byproducts of ATP synthesis and in vitro studies of cellular signaling cascades and ROS generation. There have been no direct, in vivo assessments of the changes in respiration during reperfusion. We employed phosphorescence quenching microscopy in conjunction with a flow-arrest technique to assess the influences of external, pressure-induced 1- to 10-min focal ischemia on interstitial oxygenation (PISFO2) and the consumption of oxygen (VO2) in spinotrapezius muscles of Sprague-Dawley rats. During reperfusion following an ischemic period VO2 was measured by the rate of PISFO2 decline during brief, serial flow-arrest compressions. Our tests of this intermittent compression technique indicate that 5 s of flow-arrest followed by 15 s of flow restoration allow measurement of VO2 without compromising baseline or reperfusion recovery of PISFO2. There was a steady rise in VO2 during early reperfusion which was correlated with increasing ischemic durations. Treatment with cyanide confirmed that at least some of this increase was due to an upregulation of cytochrome c oxidase activity. Nitric oxide (NO) suppressed VO2 during rest and reperfusion, while L-NAME did not influence respiration under normoxic conditions. L-NAME produced a significant rise in VO2 under hypoxic conditions following 10 minutes of ischemia, indicating a greater role of NO in the regulation of respiration during low PISFO2 conditions. We conclude that physiological levels of NO regulate mitochondrial respiration during hypoxia and confirm that pharmacological elevation of [NO] reduces VO2 in a manner consistent with the ischemic pre-conditioning effect.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Renal ischemia/reperfusion (I/R) is a main cause of acute kidney injury (AKI) and delayed graft function after renal transplantation. Previous studies in human and experimental models have identified that inflammation and oxidative stress are two key players in renal I/R injury. However, the underlying mechanisms remain speculative. The overall objective of the study was to investigate the biochemical and molecular mechanisms of I/R-induced renal injury and the effect of tyrosol supplementation on I/R-induced kidney oxidative stress damage. In the present study, renal I/R was induced in Sprague-Dawley rats and in a human kidney proximal tubular cell line. A significantly elevated expression of pro-inflammatory cytokine expression (MCP-1, IL-6) was observed. There was a significant decrease in mRNA and protein levels of two hydrogen sulphide (H2S)-producing enzymes, CBS and CSE, with a concomitant reduction of glutathione and H2S production. In the cell culture model, hypoxia–reoxygenation of proximal tubular cells led to a decrease in CBS and CSE expression and an increase in pro-inflammatory cytokine expression. Supplementation of glutathione or H2S donor (NaHS) effectively abolished cytokine expression in tubular cells. Experiments were conducted to detect oxidative stress markers. It was demonstrated that there was a significant increase in peroxynitrite formation and lipid peroxidation in the kidney after I/R insult, which might be caused by the elevation in nitric oxide (NO) metabolites and inducible nitric oxide synthase (iNOS). Administration of tyrosol, a natural phenolic compound, reduced peroxynitrite formation, lipid peroxidation and the level of NO metabolites via inhibiting NF-B activation and iNOS expression. Tyrosol treatment improved kidney function and had a protective effect against I/R-induced AKI. The present study has clearly demonstrated that (1) there is a reduction of H2S production via inhibition of CBS and CSE expression, which contributes to increased pro-inflammatory cytokine expression in the kidney and in tubular cells upon I/R insult; (2) restoration of endogenous H2S production would be of therapeutic value in regulating inflammatory response in I/R-induced kidney injury; (3) tyrosol treatment has a beneficial effect against renal I/R-induced oxidative stress, in part, through its inhibition on NF-B activation and iNOS-mediated NO production. / May 2016

Diese Dissertation beschreibt den Einfluss von HGF auf das ventrikuläre Remodeling des Rattenherzens in der 1. und 16. Woche nach Ischämie und Reperfusion. Die funktionalen Parameter wurden mit Hilfe des NMR gemessen. In der 16. Woche nach Ischämie und Reperfusion wurde die histologisch ermittelte Narbengröße mit dem Wert, der mittels NMR ermittelt wurde, verglichen. / This dissertation describes the influence of HGF on ventricular cardial remodeling of rats one week and sixteen weeks after ischemia and reperfusion. The functional parameters were calculated with NMR. Sixteen weeks after ischemia and reperfusion the scar formation was also analyzed by histologic methods. The outcomes of this method were compared with the results of the measurement with NMR.

In rats anaesthetised with enflurane, Iexamined.the response of coccygeal primary afferents fibres to noxious thermal and mechanical stimulation and to innocuous brushing, during transient ischaemia and reperfusion of their receptive fields on the tail. Ischaemia was induced by occluding the blood supply to the tail for 30 min using a tourniquet. I discovered four different groups of afferent fibres, distinguished by conduction velocity and modality, A{3fibres responding to both brush and pinch of their receptive fields showed decreased sensitivity to brush during both ischaemia and reperfusion; Ao fibres responding to pinch were unaffected by either ischaemia or reperfusion, C fibres responding to noxious heat (49· C) and pinch showed hypersensitivity during reperfusion, especially immediately after release of the tourniquet. Another group of C fibres, presumably chemosensitive, became more actiVA during ischaemia and exhibited a 7-fold increase in firing rate during receptive field reperfuslon in the absence of obvious stimuli. These results indicate that during reperfuslon of the rat tail following transient ischaemia, myelinated fibres do not increase their input to the CNS, while C fibres became more active and showed sensitization to noxious stimulation of their receptive fields. The enhanced CNS nociceptive activity which occurs during reperfusion consequently results from both peripheral and. central sensitization. / GR2017

Introdução: A torção testicular permanece como uma emergência urológica, despertando grande interesse em fármacos que podem minorar a lesão testicular e suas repercussões na fertilidade e produção hormonal. No entanto, não há fármaco aprovado para uso clínico rotineiro. Uma droga estudada em isquemia celular é a clorpromazina, sendo conhecidos seus efeitos protetores na função e estrutura da membrana celular e mitocondrial. Objetivos: Avaliar a diferença na lesão de células germinativas após 1 e 6 horas de torção e a ação da clorpromazina administrada previamente à resolução da torção no testículo isquêmico. Materiais e Métodos: 54 ratos Wistar, machos, com peso corporal entre 220 e 260 gramas distribuídos em 5 grupos: sham, controle com isquemia de 1 hora(A), controle com isquemia de 6 horas(B), experimental com isquemia de 1 hora(C) e experimental com isquemia de 6 horas(D). Em 48 animais foi realizada torção unilateral do cordão espermático com duas voltas em torno do seu eixo (720 graus), fixando-se o testículo nessa posição, após o que cada subgrupo foi separado em avaliação imediata (orquiectomia bilateral ao final do período de torção = 1) e tardia (orquiectomia bilateral, uma semana após a resolução da torção = 2). O grupo experimental recebeu 3 mg/kg de clorpromazina administrada via endovenosa, 30 minutos antes da resolução da torção. O grupo controle recebeu apenas solução salina a 0,9% por via endovenosa. Outros 6 animais formaram o grupo sham, onde foi realizada apenas a manipulação do cordão espermático. Após retiradas as gônadas, foram preparadas para análise histológica pela microscopia de luz e imunohistoquímica.Um pequeno fragmento de cada testículo foi separado para avaliação por microscopia eletrônica de transmissão (MET). Resultados: Na análise por microscopia de luz foram notadas alterações devido à isquemia como, necrose de coagulação e edema intersticial, principalmente nos grupos com isquemia mais prolongada (6h - B e D). Na avaliação por imunohistoquímica, houve maior expressão da caspase-3 nas células e túbulos dos testículos com 6 horas de isquemia, quando comparados com o grupo sham. No entanto, a expressão de bcl-2 não foi expressiva em nenhum grupo. Os grupos B e D também demonstraram alterações mais expressivas na análise por MET. Em nenhuma das avaliações foi observado superioridade do grupo da clorpromazina em relação ao grupo controle. Conclusão: As lesões celulares intratubulares induzidas pela isquemia e reperfusão testicular foram semelhantes após 1 e 6 horas, as diferenças foram relacionadas à sua maior intensidade no grupo com 6 horas e a clorpromazina não foi efetiva na prevenção da lesão por reperfusão. / Introdution: Testicular torsion remains as a urology emergency arousing interest about medicine which can reduce testicular injury and its impact on fertility and hormone production. However, there is no drug approved for routine clinical use. A drug studied in cell ischemia is chlorpromazine, being known its protective effects on the function and structure of cellular membrane and mitochondrial. Objective: To evaluate the difference in lesion of germ cells after 1 and 6 hours and the action of chlorpromazine administered before the resolution of ischemic testicle due torsion. Materials and methods: 54 male Wistar rats weighing between 220 to 260 grams divided into five groups: sham, control with one hour of ischemia (A) control with six hours of ischemia (B) experimental with one hour of ischemia (C) and experimental six hours of ischemia (D). In 48 animals was performed unilateral torsion of the spermatic cord with two laps around its axis (720 degrees), keeping the testicle in this position. After that, each subgroup was divided into immediate evaluation (bilateral orchiectomy at end of the torsion period = 1) or later (bilateral orchiectomy after one week of torsion resolution = 2). The experimental group received 3 mg / kg chlorpromazine administered intravenously 30 minutes before the resolution of torsion. The control group received only saline 0.9% intravenously. Other 6 animals were in the sham group, which was held just handling the spermatic cord. After withdrawal, the gonads were prepared for histological analysis by light microscopy and immunohistochemistry. A small piece of each testis was separated for evaluation by electron microscopy. Results: In analysis by light microscopy, ischemic changes were rated as coagulative necrosis and interstitial edema mainly in groups with prolonged ischemia (6h - B and D). When analyzed by immunohistochemistry, there was greater expression of caspase-3 in cells and tubules of the testes with 6 hour of ischemia compared to the sham group. However, bcl-2 expression was not impressive in either group. B and D groups also showed more significant changes in the analysis by electron microscopy. None of the ratings has been shown superiority of chlorpromazine group over the control group. Conclusion: The germ cell damage induced by ischemia and reperfusion was similar after 1 and 6 hours, the differences were related to its greatest intensity in the group with 6 hours and chlorpromazine was not effective in preventing reperfusion injury.

Chiu Kin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 100-116). / Abstract also in Chinese. / TABLE OF CONTENTS --- p.I / ACKNOWLEDGEMENTS --- p.V / LIST OF FIGURES --- p.VI / LIST OF ABBREVIATIONS --- p.VIII / ABSTRACT --- p.1 / Chapter 1. --- INTRODUCTION --- p.5 / Chapter 2. --- LITERATURE REVIEW --- p.7 / Chapter 2.1 --- RETINAL ISCHEMIA --- p.7 / Chapter 2.1.1 --- INDUCTION OF RETINAL ISCHEMIA --- p.7 / Chapter 2.1.2 --- MECHANISMS OF RETINAL ISCHEMIA/REPERFUSION DAMAGE --- p.8 / Chapter 2.1.2.1. --- Free radical --- p.8 / Chapter 2.1.2.2 --- Excitotoxicity --- p.9 / Chapter 2.1.3 --- APOPTOSIS IN RETINAL ISCHEMIA/REPERFUSION INJURY --- p.10 / Chapter 2.2 --- RETINAL DYSTROPHIC ROYAL COLLEGE OF SURGEONS (RCS) RAT --- p.15 / Chapter 2.3 --- BCL-2 FAMILY MEMBERS --- p.16 / Chapter 2.3.1 --- FAMILY MEMBERS AND THEIR INTERACTIONS --- p.16 / Chapter 2.3.2 --- SUBCELLULAR LOCALIZATION --- p.18 / Chapter 2.3.3 --- PHYSICAL STRUCTURE AND PORE FORMATION --- p.19 / Chapter 2.3.4 --- BIOLOGICAL EFFECTS OF BCL-2 --- p.20 / Chapter 3. --- OBJECTIVES --- p.24 / Chapter 4. --- MATERIALS AND METHODS --- p.27 / Chapter 4.1. --- RETINAL ISCHEMIA AND REPERFUSION INDUCED LOSS OF INNER RETINAL ELEMENTS --- p.27 / Chapter 4.1.1. --- TISSUE RESPONSES IN THE RAT RETINAS AFTER TRANSIENT ELEVATED INTRAOCULAR PRESSURE INDUCED RETINAL ISCHEMIA/REPERFUSION INSULT --- p.27 / Chapter 4.1.1.1. --- Induction of retinal ischemia/reperfusion insult with transient elevated intraocular pressure (IOP) --- p.27 / Chapter 4.1.1.2. --- Animal experiments --- p.28 / Chapter 4.1.1.3. --- Histopathology and measurement of inner retinal thickness (IRT) --- p.28 / Chapter 4.1.1.4. --- Flat preparation of the retinas and retinal ganglion cell counts (RGCCs) --- p.29 / Chapter 4.1.2. --- INTERNUCLEOSOMAL DNA FRAGMENTATION AND IN SITU NICKED DNA DETECTIONS AT DIFFERENT TIME AFTER REPERFUSION IN THE RAT RETINAS --- p.30 / Chapter 4.1.2.1. --- Enzyme-linked immunosorbent assay (ELISA) of mono- and oligonucleosomes --- p.30 / Chapter 4.1.2.2. --- In-situ terminal deoxynucleotidyl transferase (TdT)-mediated biotin- dUTP nicked end labelling (TUNEL) --- p.31 / Chapter 4.1.3. --- "IMMUNOHISTOCHEMISTRY OF BCL-2, BAX AND P53" --- p.32 / Chapter 4.1.4. --- "DOUBLE LABELLING OF BCL-2, BAX AND TUNEL" --- p.33 / Chapter 4.1.5. --- IN-SITU REVERSE TRANSCRIPTASE - POLYMERASE CHAIN REACTION OF BCL-2 AND BAX --- p.34 / Chapter 4.1.5.1. --- Primers design and specificity test --- p.34 / Chapter 4.1.5.2. --- In-situ RT-PCR --- p.36 / Chapter 4.2. --- LOSS OF INNER RETINAL ELEMENTS IN THE RETINAL DYSTROPHIC ROYAL COLLEGE OF SURGEONS (RCS) RATS --- p.38 / Chapter 4.2.1. --- HISTOPATHOLOGY --- p.38 / Chapter 4.2.2 --- MORPHOMETRY OF CELLS IN THE RETINAL GANGLION CELL LAYER (RGCL) AND THE INNER NUCLEAR LAYER (INL) --- p.39 / Chapter 4.2.3. --- IMMUNOHISTOCHEMISTRY OF BCL-2 AND BAX --- p.39 / Chapter 5. --- RESULTS --- p.40 / Chapter 5.1. --- RETINAL ISCHEMIA AND REPERFUSION INDUCED LOSS OF INNER RETINAL ELEMENTS --- p.40 / Chapter 5.1.1. --- TISSUE RESPONSES IN THE RAT RETINAS AFTER TRANSIENT ELEVATED INTRAOCULAR PRESSURE INDUCED ISCHEMIA/ REPERFUSION INSULT --- p.40 / Chapter 5.1.1.1. --- Histopathology --- p.40 / Chapter 5.1.1.2. --- Morphometry of inner retinal thickness --- p.40 / Chapter 5.1.1.3. --- Retinal ganglion cell counts (RGCCs) --- p.41 / Chapter 5.1.2. --- INTERNUCLEOSOMAL DNA FRAGMENTATION AND IN SITU NICKED DNA DETECTION AT DIFFERENT TIME AFTER REPERFUSION IN THE RAT RETINAS --- p.41 / Chapter 5.1.2.1. --- Enzyme-linked immunosorbent assay (ELISA) of mono- and oligonucleosomes --- p.42 / Chapter 5.1.2.2. --- In situ TUNEL --- p.42 / Chapter 5.1.3. --- BCL-2 AND RETINAL ISCHEMIA/REPERFUSION INJURY --- p.42 / Chapter 5.1.3.1. --- Immunohistochemistry of Bcl-2 --- p.42 / Chapter 5.1.3.2. --- Double labelling of Bcl-2 and TUNEL --- p.43 / Chapter 5.1.3.3. --- In situ RT-PCR for bcl-2 mRNA --- p.43 / Chapter 5.1.4. --- BAX AND RETINAL ISCHEMIA/REPERFUSION INJURY --- p.44 / Chapter 5.1.4.1. --- Immunohistochemistry of Bax --- p.44 / Chapter 5.1.4.2. --- Double labelling of Bax and TUNEL --- p.45 / Chapter 5.1.4.3. --- In situ RT-PCR for bax mRNA --- p.45 / Chapter 5.1.5. --- P53 IMMUNOREACTIVITY AT VARIOUS TIME AFTER REPERFUSION --- p.46 / Chapter 5.2. --- LOSS OF INNER RETINAL ELEMENTS IN THE RETINAL DYSTROPHIC ROYAL COLLEGE OF SURGEON (RCS) RATS --- p.47 / Chapter 5.2.1. --- HISTOPATHOLOGY --- p.47 / Chapter 5.2.2. --- MORPHOMETRY OF CELLS IN THE RGCL AND INL --- p.47 / Chapter 5.2.3. --- IMMUNOHISTOCHEMISTRY OF BCL-2 AND BAX --- p.47 / Chapter 5.2.3.1. --- Bcl-2 --- p.47 / Chapter 5.2.3.2. --- Bax --- p.48 / Chapter 6. --- DISCUSSION --- p.49 / Chapter 6.1. --- RETINA ISCHEMIA AND REPERFUSION INDUCED LOSS OF RETINAL ELEMENTS --- p.51 / Chapter 6.1.1 --- REPERFUSION TIME DEPENDENT TISSUE RESPONSES IN RAT RETINAS --- p.51 / Chapter 6.1.2 --- ISCHEMIA/REPERFUSION INDUCED APOPTOSIS IN RAT RETINAS --- p.52 / Chapter 6.1.3 --- BCL-2 AND RETINAL ISCHEMIA/REPERFUSION INSULT --- p.53 / Chapter 6.1.4 --- BAX AND RETINAL ISCHEMIA/REPERFUSION INSULT --- p.58 / Chapter 6.1.5 --- P53 AND RETINAL ISCHEMIA/REPERFUSION INJURY --- p.60 / Chapter 6.2. --- LOSS OF INNER RETINAL ELEMENTS IN THE RETINAL DYSTROPHIC ROYAL COLLEGE OF SURGEON (RCS) RAT --- p.61 / Chapter 6.2.1. --- HISTOPATHOLOGY AND MORPHOMETRY --- p.62 / Chapter 6.2.2. --- BCL-2 --- p.63 / Chapter 6.2.3. --- BAX --- p.64 / Chapter 7. --- CONCLUSION --- p.65 / APPENDIX A FIGURES --- p.66 / APPENDIX B REFERENCES --- p.100

Submitted by Eunice Novais (enovais@uepg.br) on 2018-08-17T19:14:59Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Rafael Inacio Brandão.pdf: 6353891 bytes, checksum: 8e384db8b4012f1f363df49c4c1b65b2 (MD5) / Made available in DSpace on 2018-08-17T19:14:59Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Rafael Inacio Brandão.pdf: 6353891 bytes, checksum: 8e384db8b4012f1f363df49c4c1b65b2 (MD5) Previous issue date: 2016-03-14 / A isquemia é um dos problemas mais frequentes e desafiadores com que os cirurgiões vasculares se defrontam e é ao mesmo tempo paradoxal, pois, ao restabelecer o fluxo sanguíneo para um tecido podem ser desencadeadas alterações locais ou sistêmicas mais intensas que a isquemia per se. Estas complicações estão relacionadas com a liberação de radicais livres de oxigênio. O objetivo deste estudo foi avaliar os efeitos do antioxidante alopurinol e do pós condicionamento isquêmico (PCi), que são ciclos de reperfusão intercalados com ciclos de isquemia, sobre as consequências deletérias da isquemia seguida de reperfusão em um modelo de isquemia padronizado em membros caudais de ratos. Este estudo foi aprovado pelo CEUA da Universidade Estadual de Ponta Grossa. Para tanto foram utilizados 30 ratos da linhagem Wistar, fêmeas, com aproximadamente 3 meses de idade. Os animais foram aleatoriamente distribuídos em cinco grupos: Grupo A (SHAM): animais que não foram submetidos a isquemia dos membros caudais; Grupo B : animais submetidos a 2 horas de isquemia e reperfusão apenas uma vez; Grupo C : animais receberam, por gavagem a dose de 100 mg/kg de alopurinol, uma hora antes do procedimento cirúrgico, depois foram submetidos a 2 horas de isquemia e reperfusão apenas uma vez; Grupo D: animais foram submetidos a 2 horas de isquemia e três ciclos de reperfusão (dois minutos cada) intercalados com três ciclos de isquemia (dois minutos cada) e Grupo E : animais receberam dose de 100 mg/kg de alopurinol, uma hora antes do procedimento cirúrgico, depois submetidos a 2 horas de isquemia e três ciclos de reperfusão (dois minutos cada) intercalados com três ciclos de isquemia (dois minutos cada). Três dias após foram coletadas amostras de sangue para análises bioquímicas: Ureia, Creatinina, Aspartato aminotransferase, Alanina aminotransferase, Creatinoquinase, Lactato e mensuração da capacidade antioxidante total pelo método baseado no 2,2”- azinobis 3-etilbenzotiazolina-6-ácido sulfônico (ABTS) e coleta de segmentos do intestino delgado para análises histológicas. Foi observado efeito protetor do uso de alopurinol e do Pós condicionamento isquêmico através da mensuração da creatinina, AST, ALT e lactato, que preveniram o aumento causado pela isquemia. Com relação a Capacidade Antioxidante Total, ficou evidente o benefício do PCi, mas não do alopurinol. Em relação as análises histológicas, ambos os métodos foram eficazes em minimizar os efeitos lesivos do processo de isquemia e reperfusão mesentérica. Logo pode-se concluir que, o alopurinol e mais notadamente o PCi exerceram efeito protetor, alcançando significância estatística. / Ischemia is one of the most common and challenging problems that vascular surgeons are facing and is at the same time paradoxical, therefore, to restore blood flow to a tissue can be triggered local or systemic changes more intense than ischemia per se. These complications are related to release of oxygen free radicals. The aim of this study was to evaluate the effects of allopurinol antioxidant and post ischemic conditioning on the deleterious effects of ischemia followed by reperfusion in a standardized ischemia model in rat members’ flows. This study was approved by CEUA the State University of Ponta Grossa. Therefore, we used 30 Wistar rats, female, approximately 3 months old. The animals were randomly divided into five groups: Group A (SHAM ): Animals that were not subjected to ischemia of the caudal members; Group B: Animals subjected to 2 hours of ischemia and reperfusion only once; Group C: animals were given by gavage at a dose of 100 mg / kg of allopurinol, one hour before surgery, they were then subjected to 2 hours of ischemia and reperfusion only once; Group D: Animals were subjected to 2 hours of ischemia and three reperfusion cycles (two minutes each) interleaved with three ischemia cycles (two minutes each) and Group E: Animals received 100 mg / kg of allopurinol, one hour before the surgical procedure, then subjected to 2 hours of ischemia and reperfusion for three cycles (two minutes each) interleaved with three cycles of ischemia (two minutes each). Three days after Blood samples were collected for biochemical analysis: Urea, Creatinine, Aspartate aminotransferase, Alanine aminotransferase, Creatine kinase, Lactate and measurement of the total antioxidant capacity by the method based on 2.2”- azinobis 3- ethylbenzothiazoline -6- acid sulfonic (ABTS) and collection segments of the small intestine for histological analysis. It was observed protective effect of the use of allopurinol and Post conditioning (PCi) ischemic by measuring creatinine, AST, ALT and lactate, which did not show a significant increase. Regarding the Total Antioxidant Capacity was evident the benefit of PCi, but not of allopurinol. As to the histological analyzes, both methods were effective in minimizing the harmful effects of ischemia and reperfusion process mesenteric. As a result it can be concluded that allopurinol and especially PCI exerted a protective effect, reaching statistical significance.

Introdução: A isquemia-reperfusão hepática é um fenômeno inerente aos procedimentos cirúrgicos sobre o fígado. Descrita pela primeira vez em 1975, apresenta efeitos maléficos tanto locais quanto sistêmicos que aumentam a morbidade e mortalidade dos pacientes. Dentre as formas de se atenuar o processo, a utilização de drogas anti-inflamatórias como a solução salina hipertônica a 7,5% (SSH) e a pentoxifilina vêm sendo testadas com este propósito. As duas substâncias foram utilizadas conjuntamente (HPTX) em modelos experimentais em choque hemorrágico. Contudo, na isquemia-reperfusão de origem hepática, estas foram administradas apenas isoladamente, o que torna o presente estudo pioneiro nesta avaliação. Objetivo: Avaliar os efeitos da solução salina hipertônica a 7,5% associada a pentoxifilina na isquemia-reperfusão hepática. Métodos: Foram utilizados 138 ratos Wistar divididos em quatro grupos de acordo com o tratamento empregado: GC - grupo controle (sem tratamento), SSF - solução salina fisiológica, SSH - solução salina hipertônica a 7,5% e HPTX solução salina hipertônica a 7,5% associada a pentoxifilina. A isquemia hepática foi realizada seletivamente sobre o pedículo comum do lobo mediano e ântero-lateral esquerdo pelo período de 60 minutos. As soluções foram administradas 15 minutos antes da reperfusão hepática. No sangue, foram analisadas as dosagens de transaminases hepáticas nos períodos de quatro e 12 horas e, interleucina-6 e interleucina-10 no período de 12 horas. No tecido pulmonar foram avaliadas as dosagens de azul de Evans e mieloperoxidase pulmonar nos períodos de quatro e 12 horas e, no tecido hepático do lobo isquêmico e não-isquêmico foram analisadas as dosagens de malondialdeído e a avaliação da respiração mitocondrial no período de quatro horas e a histologia nos períodos de quatro, 12 e 24 horas. Resultados: Os grupos tratados com SSH isolada ou em conjunto com a pentoxifilina apresentaram níveis significantemente menores (p<0,05) nas dosagens de transaminases e interleucina-6 em comparação aos outros dois grupos (GC e SSF). Resultados semelhantes entre os grupos foram observados no tecido pulmonar através da análise do azul de Evans e mieloperoxidase pulmonar em quatro e 12 horas e no tecido hepático com relação à respiração mitocondrial. No grupo no qual se adicionou pentoxifilina, houve diminuição estatisticamente significante da peroxidação lipídica e da permeabilidade pulmonar tardia quando comparado ao grupo SSH. Conclusões: A utilização em conjunto das duas soluções reduziu: a resposta inflamatória sistêmica; as lesões histológicas e funcionais do fígado; o estresse oxidativo e a permeabilidade pulmonar / Introduction: The liver ischemia/reperfusion (I/R) injury caused by prolonged ischemia time triggers frequently a systemic inflammatory syndrome leading to remote organ damage. Previous studies have shown that resuscitation with hypertonic saline and pentoxifylline (HPTX) attenuates hemorrhagic shock-induced injury when compared with Ringers lactate. However, it remains unclear if the HPTX protective effect occurs on liver I/R-induced injury, and if this effect overcomes the benefits of HTS used alone. Objective: Evaluated the effects of the combination of hypertonic saline solution (HTS) and pentoxifylline (PTX) on liver I/R injury in rats. Method: One hundred thirty eigth male Wistar rats underwent to one hour of partial liver ischemia performed by clamping the pedicle from the medium and left lateral lobes. Rats were divided into 4 groups: ischemia control group (C), normal saline (0.9% NaCl, 34ml/Kg) treated group (NS), hypertonic saline (7.5%NaCl, 0.4ml/Kg) treated group (HTS), and 7.5% NaCl (0.4ml/Kg) + PTX (25mg/Kg) treated group (HPTX). Samples were collected 4, 12 and 24 hours after reperfusion for determinations of serum AST, ALT, IL-6, and IL-10 levels, liver histology, liver mitochondrial oxidation and phosphorylation, and lipid peroxidation and pulmonary vascular permeability and myeloperoxidase (MPO). Results: The results showed a significant decrease in AST and ALT serum levels in HTS and HPTX groups compared to C and NS groups. Also a significant decrease in mitochondrial dysfunction was observed in HTS and HPTX groups compared to C and NS groups. The oxidative stress was significant decreased in HPTX group compared to C, NS and HTS groups in both ischemic and non-ischemic liver lobes. Elevation in serum IL-6 was significantly lower in HTS and HPTX groups compared to C and NS groups, but there was no difference in IL-10 levels. Pulmonary vascular permeability was significantly lower in groups HTS and HPTX compared with NS group, and even lower in HPTX group compared to HTS group (P < .05). Conclusion: These data suggest that addition of pentoxifylline to hypertonic saline solution decreases the inflammatory response of the liver ischemia/reperfusion injury, decreasing the liver damage as well the pulmonary injury