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PURPOSE: To evaluate the vas deferens and testicles of rats submitted to bilateral inguinotomy and polypropylene (PP) mesh placement. METHOD: Sixty Wistar rats were randomized into three groups: Control (inguinotomy only), mesh placement over the vas deferens (Mesh-DD) or under the spermatic funiculus (Mesh-SF). The following analyses were performed: vas deferens morphometry (lumen area and wall thickness), quantification of collagen fibers, spermatogenesis, apoptosis (cleaved caspase-3 and TUNEL) and cellular proliferation (Ki67). Quantitative gene expression (qPCR) for apoptosis and inflammatory cytokines were evaluated by RT-PCR. RESULTS: In the apoptosis pathway, Mesh-DD showed one upregulated gene (Il10) and three downregulated genes (Fadd, Tnfrsf1b and Xiap). In Mesh-SF, 17 genes were downregulated. In the inflammation pathway (Mesh-DD), one gene was upregulated (Il1r1), and one gene was downregulated (Ccl12). In Mesh-SF, three genes were upregulated (Il1r1, Tnfsf13b and Csf1), and two were downregulated (Ccl12 and Csf2). PP mesh placement preserved spermatogenesis and did not alter the vas deferens or the testicle. In the ductus deferens, there was reduced luminal area (30 days), increased wall thickness (90 days), and increased type III collagen and cell proliferation (30 and 90 days) (p < 0.05). In the testicle, cell proliferation was greater in the Mesh-DD (p < 0.05). CONCLUSIONS: PP mesh, whether or not in direct contact with spermatic funicular structures, induces changes that were not sufficient to cause damage to the evaluated organs.
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Genitales/cirugía , Polipropilenos/uso terapéutico , Mallas Quirúrgicas/normas , Animales , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas WistarRESUMEN
Intestinal ischemia and reperfusion injury are widely used models, which result into tissue injury and multiple organ failure also observed after trauma and surgery. Ischemic preconditioning (IPC) preceding ischemia and reperfusion (IR) was shown to attenuate this injury and has a potential therapeutic application; however the exact underlying mechanism is not clear. Neutrophils play an important role in the mechanism of injuries caused by ischemia and reperfusion while IPC led to a decrease in neutrophil stimulation and activation. The effect of preconditioning on the neutrophil proteome is unclear. Proteomic analysis has been ratified as an appropriate tool for studying complex systems. In order to evaluate the effect of IPC preceding 45min of ischemia on the proteome of neutrophils we used Wistar rats divided in four experimental groups: Control, sham laparotomy, intestinal ischemia reperfusion and ischemic preconditioning. After neutrophil separation, proteins were extracted, trypsin digested and the resulting peptides were iTRAQ labeled followed by HILIC fractionation and nLC-MS/MS analysis. After database searches, normalization and statistical analysis our proteomic analysis resulted in the identification of 2437 protein groups that were assigned to five different clusters based on the relative abundance profiles among the experimental groups. The clustering followed by statistical analysis led to the identification of significantly up and downregulated proteins in IR and IPC. Cluster based KEGG pathways analysis revealed up- regulation of actin cytoskeleton, metabolism, Fc gamma R mediated phagocytosis, chemokine signaling, focal adhesion and leukocyte transendothelial migration whereas downregulation in ribosome, spliceosome, RNA transport, protein processing in endoplasmic reticulum and proteasome, after intestinal ischemic preconditioning. Furthermore, enzyme prediction analysis revealed the regulation of some important antioxidant enzymes and having their role in reactive oxygen species production. To our knowledge, this work describes the most comprehensive and detailed quantitative proteomic study of the neutrophil showing the beneficial role of ischemic preconditioning and its effects on the neutrophil proteome. This data will be helpful to understand the effect of underlying protective mechanisms modulating the role of PMNs after IPC and provide a trustworthy basis for future studies. BIOLOGICAL SIGNIFICANCE: Preconditioning is a relevant strategy to overcome clinical implications from ischemia and reperfusion. Such implications have the neutrophil as a major player. Although many publications describe specific biochemical and physiological roles of the neutrophil in such conditions, there is no report of a proteomic study providing a broader view of this scenario. Here we describe a group of proteins significantly regulated by ischemia and reperfusion being such regulation prevented by preconditioning. Such finding may provide relevant information for a deeper understanding of the mechanisms involved, as well as serve as basis for future biomarker or drug target assays.
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Precondicionamiento Isquémico , Neutrófilos/química , Proteoma/análisis , Proteómica/métodos , Animales , Movimiento Celular , Análisis por Conglomerados , Intestinos/patología , Oxidorreductasas , Ratas , Ratas Wistar , Daño por Reperfusión , Proteínas Ribosómicas/análisisRESUMEN
The aim of this study was evaluate the beta blocker atenolol (AT) and ischemic preconditioning (IPC) strategies for tissue protection against systemic effects of intestinal ischemia (I) and reperfusion (R) injury. Forty-two rats were pretreated with AT (1.5 mg · kg(-1)), 0.9% saline solution (SS; 0.1 mL), or IPC and then subjected to prolonged occlusion of the superior mesenteric artery for 60 minutes leading to I followed or not by 120 minutes of R, according to the group. For IPC, 5 minutes of I prior to 10 minutes of R were established. After this process of I or I-R, the right lung of each animal was adequately prepared for staining with hematoxylin and eosin and subsequent histologic analysis for quantification of inflammatory infiltrate was done. The left lung was frozen and prepared for assessment of oxidative stress by the quantification of thiobarbituric acid-reactivity substances (TBARS). Histologic analysis showed an important inflammatory infiltrate in the I-R + SS (I-R + SS = 4.5), which was significantly (P < .05) reduced by IPC (I-R + IPC = 3.0) or AT (I-R + AT = 3.0). Likewise, the TBARS levels were decreased by both strategies (I-R + SS = 0.63; I-R + IPC = 0.23; I-R + AT = 0.38; P < .05). Our results showed that AT and IPC attenuate pulmonary lesions caused by intestinal I and R process.
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Atenolol/farmacología , Intestinos/irrigación sanguínea , Precondicionamiento Isquémico/métodos , Lesión Pulmonar/prevención & control , Pulmón/irrigación sanguínea , Daño por Reperfusión/prevención & control , Antagonistas de Receptores Adrenérgicos beta 1/farmacología , Animales , Modelos Animales de Enfermedad , Lesión Pulmonar/etiología , Masculino , Ratas , Ratas Wistar , Daño por Reperfusión/complicacionesRESUMEN
To study the role of heparin and ischemic preconditioning (IPC) in cardiac injury after intestinal ischemia (I) and reperfusion (R), 54 rats underwent 60 minutes of I, which was produced by occlusion of the superior mesenteric artery, and/or 120 minutes of R. The IPC group had the I procedure stimulation for 5 minutes and R for 10 minutes. The control group was subjected to sham surgery only, and the other groups were injected with saline solution (SS; 0.1 mL) or heparin (100 IU/kg) via the inferior cava vein 5 minutes before I and 5 minutes before R and 55 minutes after the R begins in I-R groups. In all animals, cardiac samples were stained with hematoxylin and eosin for optical microscopy analysis, and other sample was processed for lipid peroxidation determination. In I-R groups, both heparin and IPC showed significant protection compared to the SS group; conversely, in animals subjected only to I, no protection was observed. Moreover, when heparin was associated with IPC, I-R protection was compromised and the ischemic injury increased. Data showed that IPC and heparin attenuated cardiac dysfunction caused by intestinal I and I-R, but when used in association did not show beneficial effects.
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Cardiomiopatías/prevención & control , Heparina/uso terapéutico , Intestinos/irrigación sanguínea , Precondicionamiento Isquémico/métodos , Daño por Reperfusión/prevención & control , Animales , Anticoagulantes/uso terapéutico , Cardiomiopatías/etiología , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas Wistar , Daño por Reperfusión/complicacionesRESUMEN
Surgery to transfer the axillary nerve and the nerve of the long head of the triceps presents two obstacles: 1) the access portals are not standardized and 2) the nerves are for their larger part approached through large incisions. The goal of this study was to explore the feasibility of an endoscopic microsurgical approach. The posterior aspect of a cadaver shoulder was approached through three communicating mini-incisions. The Da Vinci robot camera was installed on a central trocart, and the instrument arms on the adjacent trocarts. A gas insufflation distended the soft tissues up to the lateral axillary space. The branches of the axillary nerve and the nerve to the long head of the triceps brachii muscle were identified. The dissection of the axillary nerve trunk and its branches was easy. The posterior humeral circumflex veins and artery were dissected as well without any difficulty. Finding the nerve to the long head of the triceps brachii was found to be more challenging because of its deeper location. Robots properties allow performing conventional microsurgery: elimination of the physiologic tremor and multiplication of the movements. They also facilitate the endoscopic approach of the peripheral nerves, as seen in our results on the terminal branches of the axillary nerve and the nerve to the long head of the triceps brachii.
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Axila/inervación , Plexo Braquial/cirugía , Microcirugia/métodos , Robótica , Axila/cirugía , Cadáver , Estudios de Factibilidad , HumanosRESUMEN
To study whether treatment with the beta-blocker atenolol (AT) attenuates intestinal dysfunction caused by ischemia (I) and reperfusion (R), rats were treated with AT (1.5 mg · kg(-1), intravenously) or saline solution (SS) prior to I (60 minutes), which was produced by occlusion of the superior mesenteric artery, and/or R (120 minutes). After I or I/R, 2-cm jejunal segments were mounted in an organ bath to study neurogenic contractions stimulated by electrical pulses or KCl using a digital recording system. Thin jejunal slices were stained with hematoxylin and eosin for optical microscopy analysis. Compared to the sham group, jejunal contractions were similar in the I + AT and the I/R + AT groups, but reduced in the I + SS and the I/R + SS groups. The jejunal enteric nerves were damaged in the I + SS and the I/R + SS groups, but not in the I + AT and the I/R + AT. These results suggest that AT may attenuate intestinal dysfunction caused by I and I/R.
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Antagonistas de Receptores Adrenérgicos beta 1/farmacología , Atenolol/farmacología , Fármacos Gastrointestinales/farmacología , Yeyuno/irrigación sanguínea , Yeyuno/efectos de los fármacos , Daño por Reperfusión/prevención & control , Animales , Citoprotección , Modelos Animales de Enfermedad , Estimulación Eléctrica , Sistema Nervioso Entérico/efectos de los fármacos , Sistema Nervioso Entérico/fisiopatología , Motilidad Gastrointestinal/efectos de los fármacos , Yeyuno/inervación , Yeyuno/patología , Yeyuno/fisiopatología , Masculino , Cloruro de Potasio/farmacología , Ratas , Ratas Wistar , Daño por Reperfusión/patología , Daño por Reperfusión/fisiopatologíaRESUMEN
BACKGROUND: Dysfunction of the liver after transplantation may be related to the graft size and ischemia/reperfusion (I/R) injury. N-Acetylcysteine (NAC) exerts beneficial effects on livers undergoing ischemia reperfusion. We sought to evaluate NAC modulation on reduced livers associated with I/R injury. METHODS: Male C57BL/6 mice of 8 weeks of age were divided into groups: 50% hepatectomy (G-Hep); NAC (G-Hep + NAC [150 mg/kg]) via vena cava 15 minutes before hepatectomy; ischemia (G-Hep + IR); NAC with hepatectomy (G-IR + Hep + Nac); and IR using 30 minutes selective hepatic occlusion and reperfusion for 24 hours. After 24 hours, the remaining liver was removed, for staining with hematoxylin and eosin or labeling by proliferating cell nuclear antigen. Blood was collected for biochemical evaluations. Significance was considered for P ≤ .05. RESULTS: Aspartate aminotransferase was high in all studied groups reflecting the hepatectomy and intervention. injuries. However, when assessing alanine aminotransferase, which depicts liver function, induction of IR promoted a greater increase than hepatectomy (P = .0003). NAC decreased ALT activity in all groups, even in association with I/R (P < .05), reflecting a modulation of the injury. Necrosis resulting from IR was mitigated by NAC. The experimental model of 50% reduced live promoted regeneration of the hepatic remnant, which was accentuated by NAC, according to the total number of hepatocytes and PCNA values. CONCLUSION: NAC preserved the remnant liver in mice and stimulates regeneration even after IR injury.
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Acetilcisteína/farmacología , Proliferación Celular/efectos de los fármacos , Hepatectomía , Regeneración Hepática/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/cirugía , Daño por Reperfusión/tratamiento farmacológico , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Biomarcadores/sangre , Biomarcadores/metabolismo , Citoprotección , Modelos Animales de Enfermedad , Inmunohistoquímica , Hígado/irrigación sanguínea , Hígado/metabolismo , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Necrosis , Antígeno Nuclear de Célula en Proliferación/metabolismo , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Factores de TiempoRESUMEN
PURPOSE: The purpose of this study was to establish morphologically the best time of vascular occlusion to induce ischemic preconditioning (IPC) for rat small bowel undergoing ischemia and reperfusion injury. METHODS: After approval by the Ethics Committee, 36 EPM-1 young adult Wistar rats from 300-350 g were distributed into 6 groups: sham (S); ischemia and reperfusion (IR), with 50 minutes of cranial mesenteric artery occlusion and 30 minutes of reperfusion; IPC with 1 cycle of 2 minutes (IPC-2), 5 minutes (IPC-5), 10 minutes (IPC-10), or 15 minutes (IPC-15), followed by sustained IR. The animals anesthetized with ketamine (60 mg/kg) and xylazine (10 mg/kg) intramuscular (IM), were maintained on mattress heat, hydrated with saline (80 mL/kg), and injected with 100 IU heparin. Samples of jejunum were stained with hematoxylin and eosin (HE) and classified according to Park et al. Statistical analysis of results was performed using Kruskal-Wallis tests (P < .05). RESULTS: The histological evaluation showed no difference between IR and IPC15 rats (5.2 and 5, respectively; P = .84). Greater jejunal injury was observed with IPC15 (5) compared with other groups (IPC2 = 3, P = .03; IPC5 = 3.2, P = .05; IPC10 = 2.8, P = .02, respectively). There was no difference between groups IPC2 x IPC5 x IPC10. CONCLUSION: Morphologically, IPC with short times promoted greater intestinal protection against the IR lesion in rats.
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Intestino Delgado/fisiopatología , Precondicionamiento Isquémico/métodos , Daño por Reperfusión/fisiopatología , Animales , Mucosa Intestinal/lesiones , Mucosa Intestinal/patología , Intestino Delgado/patología , Isquemia , Masculino , Ratas , Ratas Wistar , Reperfusión , Daño por Reperfusión/patología , Daño por Reperfusión/prevención & controlRESUMEN
PURPOSE: The purpose of this study was to evaluate estradiol serum levels and follicular development in rats subjected to ovarian autologous transplantation with or without remote ischemic preconditioning (R-IPC). METHODS: Seventy-two adult female Wistar EPM-1 rats were distributed into 3 groups: (1) controls; (2) ovarian transplantation; and (3) ovarian transplantation + R-IPC. The groups were divided into subgroups, according to the prefixed date for euthanasia: 24 hours, 48 hours, 72 hours, and 7th postoperative day (PO). R-IPC was performed by clamping the common iliac artery for a 15-minute period of ischemia followed by 15 minutes of reperfusion, before undergoing ovarian transplantation. The graft was fixed to the retroperitoneum with a simple 8-0 prolene thread. Blood samples were collected from the vena cava. For evaluation of follicular development, the ovarian follicles were classified as immature and mature follicles besides corpora lutea. Only the viable follicles and functioning corpora lutea were counted. RESULTS: At 72 hours, the R-IPC group showed higher estradiol values than the other groups, which were similar. After 24 hours the mean values were similar among all groups, and at 48 hours the R-IPC group was similar to the transplanted group without IPC. Animals undergoing R-IPC showed superior morphologic aspects, but 7 days after transplantation the morphology was worse in all groups. R-IPC enhanced the number of immature follicles at 48 hours (P > .05) and number of mature follicles from 24 hours to 48 hours after transplantation (P < .01). Functioning corpora lutea number was increased as well. CONCLUSION: R-IPC increased the estradiol levels in autologous ovarian transplants associated with better graft morphology and more mature follicles.
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Estradiol/sangre , Precondicionamiento Isquémico/métodos , Folículo Ovárico/fisiología , Ovario/trasplante , Animales , Cuerpo Lúteo/patología , Cuerpo Lúteo/fisiología , Femenino , Inflamación/patología , Necrosis , Folículo Ovárico/patología , Ovariectomía , Ovario/patología , Ratas , Ratas Wistar , Valores de Referencia , Trasplante Isogénico/patologíaRESUMEN
OBJECTIVE: Usually an experimental necrotizing enterocolitis experimental model, we Investigated nitric oxide levels in intestinal tissues of newborn mice with or without l-arginine therapy during sessions of ischemia and reoxygenation. METHODS: Twenty-six newborn mice from the Wistar EPM-1 lineage, weighing from 4.5 to 6.2 g, were randomly assigned to three groups: G-I/R, hypoxia and reoxygenation; G-Arg, l-arginine treatment I/R; and G-CTL, controls. G-I/R and G-Arg mice underwent twice a day during their first 3 days of life exposure to gas chambers with 100% CO(2) for 5 minutes at 22 degrees C before reoxygenation with 100% O(2) for another 5 minutes. After 12 hours, all animals were sedated, laparotomized, and had samples of ileum and colon taken and- either formalin fixed histopathologic examinations or frozen to -80 degrees C for estimation of tissue nitric oxide levels. Intestinal injuries were classified according to the criteria of Chiu et al. RESULTS: The G-I/R and G-Arg groups showed injuries characteristic of necrotizing enterocolitis (NEC) with an improved structural preservation rate in G-Arg. The concentration of nitric oxide in the Ileum was much higher with G-Arg (16.5 +/- 4.9; P = 0.0019) G-I/R (7.3 +/- 2.0). This effect was not observed in the colon: G-I/R = 10.7 +/- 4.6 versus G-Arg = 15.5 +/- 8.7 (P = .2480). CONCLUSION: Supply of L-arginine increased tissue levels of nitricoxide and reduced morphologic intestinal injury among mice undergoing I/R.
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Arginina/uso terapéutico , Mucosa Intestinal/metabolismo , Intestinos/irrigación sanguínea , Óxido Nítrico/metabolismo , Daño por Reperfusión/metabolismo , Animales , Animales Recién Nacidos , Ratones , Ratones Endogámicos , Trasplante HomólogoRESUMEN
PURPOSE: Verify the optimum remote vascular occlusion time to reduce ovarian injury in autologous transplants in rats. METHODS: Twenty-four adult female rats were assigned to four groups: GC (control group): bilateral oophorectomy followed by ovary transplant; GIPC (ischemic preconditioning group): remote ischemic preconditioning at the iliac artery for 5, 10, and 15 minutes (GIPC-5, GIPC-20, and GIPC-15) previous to bilateral oophorectomy and ovarian transplantation. The right ovary was fixed in the retroperitoneum. Euthanasia was performed 4 days after the surgical procedure. The follicles were counted and classified as developing versus atretic. The immunohistochemical assay identified vascular factor of endothelial growth (VEGF) in the ovarian stroma and assessed the proliferation capacity by means of the Ki-67 in the ovarian follicles. RESULTS: Every group showed an inflammatory infiltrate, luteous body, and ovarian follicles in several phases of development. The ischemic preconditioning groups displayed greater amounts of viable ovarian follicles and increased vascularization and vasodilatation than the control group. GIPC-15 showed the highest amount of viable follicles compared to the others (P < .05 GIPC-15 vs GC; GIPC-15 vs GIPC-5). More VEGF-labeled cells were observed in GIPC-10 than the control group (P < .05, GIPC-10 vs GC). The proliferation index assessed by Ki-67 marking showed GC: 80%; GIPC-5: 76%; GIPC-10: 67%; and GIPC-15: 64% (P > .05). CONCLUSIONS: The PCI-15 cohort seem to be the most adequate timing to achieve functional support and preservation of a greater number of viable ovarian follicles.
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Precondicionamiento Isquémico/métodos , Folículo Ovárico/citología , Ovario/trasplante , Animales , Femenino , Modelos Animales , Folículo Ovárico/irrigación sanguínea , Ovariectomía , Ratas , Ratas Wistar , Trasplante AutólogoRESUMEN
The efficiency of software for a personal computer in the interactive generation of three-dimensional (3D) images from computer tomography was studied in six pig livers after hepatic resection and catheterization of the hepatic and portal veins. After perfusion the livers were submitted to computed tomography angiography, volumetric measurement by water displacement, and production of an acrylic model of the veins by the injection and corrosion method, by which the lengths of the hepatic and portal veins were measured. From the angiogram, the software generated a 3D image that allowed measurement of the vein lengths. The identified branches of the hepatic and portal veins were correlated with the hepatic sectors and segments, respectively. The virtual measures from the 3D images were compared with the real measures. There were no significant differences between the topography and the vessel length. The mean difference between the volumes calculated from software and those measured by water displacement corresponded to 1.2%, and between the vessel lengths, 0.2%. In conclusion, the software for personal computer (named LIVER3D) is efficient, allowing interactive inspection of 3D images. All virtual measurements of liver vessel length and partial/total liver volume were similar to the actual ones.
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Hígado/anatomía & histología , Microcomputadores , Animales , Procesamiento de Imagen Asistido por Computador , Circulación Hepática , Vena Porta/anatomía & histología , Programas Informáticos , Porcinos , Interfaz Usuario-Computador , Vena Cava Inferior/anatomía & histologíaRESUMEN
AIM: To study the effects of N-acetylcysteine and ischemic preconditioning on the portal triad clamping compared to arterial and portal clamping alone. METHODS: Eighty EPM 1-Wistar rats were randomized into two groups, depending on inclusion (Group 1) or not (Group 2) of the bile duct in the hepatic vascular pedicle occlusion. Each group was divided into four subgroups as follows. IR 1: 20 minutes after celiotomy, the pedicle containing vascular elements and bile duct to the left lateral and median liver lobes was occluded for 40 minutes, followed by 30 minutes of reperfusion. IPC 1: after 10 minutes of ischemia and 10 minutes of reperfusion, the ischemic preconditioning period, the rats were submitted to the same procedure described for IR 1 Group. NAC 1: the rats received N-acetylcysteine (150 mg/kg) 15 minutes before 40 minutes of ischemia and 5 minutes before 30 minutes of reperfusion. SHAM 1: The hepatic pedicle for the lateral and median liver lobes was dissected after 20 minutes, the bile duct alone was clamped for 40 minutes, and released for an additional 30 minutes. In the IR 2, IPC 2, and NAC 2 groups, ischemia was achieved with an exclusive vascular occlusion. SHAM 2: dissection and observation for 90 minutes. The blood was sampled for liver enzyme levels. Statistical analysis was done (P
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Acetilcisteína/farmacología , Conductos Biliares/fisiología , Precondicionamiento Isquémico , Circulación Hepática/fisiología , Daño por Reperfusión/prevención & control , Alanina Transaminasa/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Aspartato Aminotransferasas/metabolismo , Bilirrubina/metabolismo , Circulación Hepática/efectos de los fármacos , Masculino , Sistema Porta , Ratas , Ratas Wistar , gamma-Glutamiltransferasa/metabolismoRESUMEN
This article seeks to standardize an experimental model of liver ischemia-reperfusion in rats following hemorrhagic shock modulated by N-acetylcysteine (NAC). Twenty-seven adult Wistar rats were randomized into three groups: the HS-IR-Garm underwent hemorrhagic shock with selective hepatic ischemia followed by reperfusion; the HSIR + NAC-G, the same procedure plus NAC; and the control group, only venous catheterization. Blood was withdrawn for 10 minutes until MABP reached 35 mm Hg, which was maintained for 1 hour. The blood was then reinjected as required to maintain MABP at that level. Ringer's lactate solution was infused in a volume equivalent to three times the shed blood, over a period of 15 minutes. Half of the shed blood was reinfused over 5 minutes. HSIR + NAC-G received 150 mg/kg of NAC, during treatment of the shock, and again 10 minutes before reperfusion and continued for 30 minutes. Finally, both groups were subjected to 40 minutes of warm selective hepatic ischemia and reperfusion for 1 hour. Data were analyzed by nonparametric tests (P < or =.05). Liver enzyme levels were higher in HS-IR-G (DHL = 6094 +/- 1688, AST = 746 +/- 175, and ALT = 457 +/- 90) than in HSIR + NAC-G group (DHL = 2920 +/- 284, AST = 419 +/- 113, and ALT = 253 +/- 26). The values in the control group were lower than both experimental groups (DHL = 965 +/- 173, AST = 163 +/- 42, and ALT = 82 +/- 28). Our data showed that liver ischemia-reperfusion injury following hemorrhagic shock produces important hepatic damage and that NAC reduces injury in this rat model.
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Acetilcisteína/uso terapéutico , Hígado/irrigación sanguínea , Daño por Reperfusión/prevención & control , Choque Hemorrágico/prevención & control , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Modelos Animales de Enfermedad , L-Lactato Deshidrogenasa/sangre , Hígado/patología , Pruebas de Función Hepática , Ratas , Ratas WistarRESUMEN
This study investigated the effect of gangliosides (Gang) on small bowel microcirculation and animal survival after normothermic intestinal ischemia-reperfusion injury. Five adult male EPM-1 Wistar rats in each of three groups received FK506 (0.2 mg/kg), Gang (3 mg/kg), or vehicle (at same volume) either 24 or 12 hours prior to the experiment. The animals were anesthetized intramuscularly with ketamine (60 mg/kg) and xylazine (10 mg/kg) and hydrated with 80 mL/kg of prewarmed saline solution delivered subcutaneously before the ischemic insult and 40 mL/kg at 1 hour after reperfusion. Under anesthesia, they underwent a laparotomy with clamping of the superior mesenteric artery (SMA) at its origin for 75 minutes. Microcirculation was evaluated with a laser Doppler flowmeter, 5 minutes before ischemia (baseline) and reperfusion (ischemia), and 20, 40, and 60 minutes after reperfusion. Animal survival was observed up to 24 hours. Small bowel flow measured before ischemia was considered to be the baseline level (100%). After SMA occlusion a significant reduction in microcirculatory tissue perfusion to about 8% was observed in all groups. At 20, 40, and 60 minutes of reperfusion treatment with Gang (77%, 81%, and 100%) or FK506 (70%, 85%, and 98%) promoted better recovery of the intestinal microcirculation when compared to the control group (45%, 72%, and 75%). Concerning animal survival there was no difference between groups (just one animal from each group, Gang and FK506, survived up to 24 hours). Based on our data we conclude that Gang and FK506 improve intestinal microcirculation in ischemia-reperfusion injury but do not change animal survival after severe ischemia.
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Gangliósidos/farmacología , Intestinos/irrigación sanguínea , Microcirculación/efectos de los fármacos , Daño por Reperfusión/prevención & control , Tacrolimus/farmacología , Animales , Citometría de Flujo , Inmunosupresores/farmacología , Intestinos/efectos de los fármacos , Intestinos/patología , Masculino , Ratas , Ratas WistarRESUMEN
The objective of this study was to evaluate the effect of ischemic preconditioning upon lesions produced by ischemia-reperfusion of the small intestine. Thirty EPM-1 Wistar rats were randomly distributed into three groups: ischemic preconditioning (IPC; n = 12), ischemia-reperfusion (I/R; n = 12), and control (C; n = 6). Laparotomy permitted isolation of the mesenteric artery for clamping. The animals were heparinized and hydrated. IPC was induced by: 10 minutes of ischemia followed by 10 minutes of reperfusion and then 50 minutes ischemia followed by another 30 minutes reperfusion. Group I/R was submitted to the same protocol except for the 20 minutes of preconditioning. Group C animals underwent only laparotomy for 100 minutes. After reperfusion small intestine fragments were examined histologically. Blood samples were obtained to measure LDH and lactate prior to euthanasia. Lactate values were significantly lower in the IPC as compared to I/R group, 39 versus 67 mg/dL, respectively (P < or =.05). However, neither IPC (grade 3) lesions of the mucosa versus I/R (grade 4) nor LDH values (PCI = 680, I/R = 873 U/L) were statistically different. Thus No morphological evidence of protection was observed following ischemic preconditioning.
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Intestino Delgado/patología , Precondicionamiento Isquémico , Daño por Reperfusión/prevención & control , Animales , Modelos Animales de Enfermedad , Intestino Delgado/irrigación sanguínea , Masculino , Ratas , Ratas Wistar , Valores de Referencia , Daño por Reperfusión/patologíaRESUMEN
OBJECTIVE: To study the effects of extensive intestinal resection on growing rats, with regard to animal weight and histomorphometry of the remaining small intestine. METHODS: Forty growing rats were allocated according to the extent of small intestine resection: 60%, 70%, 80%, or 90%. The animals were weighed every week and observed for 30 days. Following sacrifice the remaining small intestine was resected, fixed in 10% formol for 24 hours, embedded in paraffin, and stained using hematoxylin and eosin. The histological changes in the remaining small intestine were assessed for the length and thickness of villi, the thickness of the muscle layer, and the number of intestinal glands. RESULTS: All growing rats showed a fall in body weight, although it was more significant with the largest intestinal resection (80% and 90%). Villus length and muscle thickness increased after 30 postoperative days in all rats, but the number of intestinal glands remained unaltered. CONCLUSION: Growing rats with greatest resection of small intestine (80% and 90%) had better intestinal adaptation and slower recovery of body weight.
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Intestino Delgado/trasplante , Animales , Peso Corporal , Mucosa Intestinal/citología , Mucosa Intestinal/patología , Mucosa Intestinal/trasplante , Intestino Delgado/citología , Intestino Delgado/patología , Masculino , Microvellosidades/ultraestructura , Modelos Animales , Periodo Posoperatorio , Ratas , Ratas WistarRESUMEN
Microcirculatory disturbances have been related to a decrease in survival after liver transplant. Because innervation is involved in liver hemodynamics regulation, we decided to evaluate microcirculatory hepatic perfusion. Thirty rats were divided into three groups: denervated (DG), hepatic microsurgical denervation; manipulated (MG), hepatic manipulation; control (CG), laparotomy. Hepatic microcirculation was assessed in the median lobe using laser Doppler flowmetry in the following moments: T(0), after laparotomy and T(1), after denervation; and in the following moments after denervation: T(2), 10 minutes, T(3), 20 minutes, T(4), 30 minutes, T(5), 1 hour, T(6), 1.5 hours, and T(7), 2 hours for DG, and in same moments for MG and CG. DG showed a decrease in hepatic perfusion for 20 minutes after denervation, different from MG and CG. After that, there was recovery in hepatic perfusion in MG and DG (Kruskal-Wallis and Friedman tests). Therefore, denervation and manipulation alter hepatic microcirculation, but denervation promotes a more severe decrease than manipulation.
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Desnervación , Hígado/irrigación sanguínea , Microcirugia , Animales , Velocidad del Flujo Sanguíneo/fisiología , Flujometría por Láser-Doppler , Hígado/inervación , Trasplante de Hígado/fisiología , Masculino , Microcirculación/fisiopatología , RatasRESUMEN
Previous studies demonstrated that some immunosuppressive agents inhibit arterial intimal hyperplasia. Our previous studies demonstrated that gangliosides (Gang) have an immunosuppressive effect on as well as an anti-inflammatory role in the wound-healing process. Therefore, we decided to examine the effect of Gang on intimal hyperplasia. Twenty Wistar isogenic rats received a transverse division of the anterior wall of the femoral artery, followed by suturing using mononylon 10-0 under surgical microscopy and were then divided into two groups: Gang group, 3 mg/kg per day of Gang, and control group, vehicle, intramuscularly from surgery to death (1 and 3 weeks, respectively). Concentric intimal hyperplasia was observed in arteries stained by hematoxylin-eosin in control and Gang groups. However, the media layer did not demonstrate any major alterations. After 3 weeks, the Gang group showed more intimal hyperplasia than the control group. Therefore, because intimal hyperplasia worsened in the presence of Gang after 3 weeks, further studies will be necessary to clarify its role in intimal proliferation.