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1.
Thorac Cardiovasc Surg ; 66(1): 99-108, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28655065

RESUMO

BACKGROUND: Acute mesenteric ischemia following cardiovascular surgery is a rare but fatal complication. We established a new rat model for hemodynamic monitoring during mesenteric ischemia/reperfusion (I/R) and evaluated the impact of mesenteric I/R on hemodynamics and remote organ injury. METHODS: Mesenteric I/R was induced in male Wistar rats by superior mesenteric artery occlusion for 90 minutes, followed by 120 minutes of reperfusion. Before I/R, ventilation and hemodynamic monitoring including mean arterial blood pressure (MAP) and cardiac output (CO) were established. During reperfusion Geloplasma (I/R + Geloplasma, N = 6) and Ringer's solution (I/R + Ringer, N = 6) were titrated according to CO and compared with I/R without volume resuscitation (I/R only, N = 6) and a sham group (sham, N = 6). Blood samples were regularly taken for serum marker measurements. After reperfusion organs were harvested for histology studies. RESULTS: After acute mesenteric I/R, MAP and CO decreased (p < 0.01) while systemic and pulmonary vascular resistance increased (p < 0.01) continuously in the I/R group. Volume substitution according to CO initially stabilized hemodynamic parameters, but CO declined independently in the late stage. Compared with the I/R + Ringer group, the I/R + Geloplasma group required less volume for resuscitation (p < 0.01), experienced less metabolic acidosis. I/R groups had more organ injuries, more neutrophils sequestration, and higher creatine phosphokinase-MB levels than sham group. CONCLUSION: A new model for CO monitoring after mesenteric I/R injury demonstrated severe hypovolemic shock during reperfusion followed by remote myocardial and lung injury. Far less colloid volume is needed for hemodynamic stabilization after I/R compared with crystalloid volume.


Assuntos
Gelatina/toxicidade , Hemodinâmica , Intestinos/irrigação sanguínea , Soluções Isotônicas/toxicidade , Isquemia Mesentérica/terapia , Traumatismo por Reperfusão/fisiopatologia , Reperfusão/efeitos adversos , Acidose/sangue , Acidose/etiologia , Acidose/fisiopatologia , Animais , Pressão Arterial , Biomarcadores/sangue , Débito Cardíaco , Modelos Animais de Doenças , Gelatina/administração & dosagem , Intestinos/patologia , Soluções Isotônicas/administração & dosagem , Pulmão/irrigação sanguínea , Pulmão/patologia , Lesão Pulmonar/etiologia , Lesão Pulmonar/patologia , Lesão Pulmonar/fisiopatologia , Masculino , Isquemia Mesentérica/sangue , Isquemia Mesentérica/patologia , Isquemia Mesentérica/fisiopatologia , Miocárdio/patologia , Ratos Wistar , Reperfusão/métodos , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Lactato de Ringer , Fatores de Tempo , Resistência Vascular
2.
Mol Med Rep ; 16(4): 4334-4340, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28731176

RESUMO

The aim of the current study was to investigate the cytotoxic effects of hypotonic (iopamidol) and isotonic (iodixanol) contract media (CMs) in vitro and in vivo. A total of 60 Wistar rats were included and were randomly divided into three groups (20 rats per group). Iodixanol (4 g iodine/kg), iopamidol (4 g iodine/kg) or equal volume of normal saline was injected via tail vein. HUVEC and H5V cell viability was determined by Cell Counting Kit­8 agents. Western blotting was performed to detect ATP­binding cassette subfamily G member 1 (ABCG1) expression. For histological analysis, hematoxylin and eosin staining was performed. Plasma endothelin, von Willebrand factor, tissue type plasminogen activator, plasminogen activator inhibitor, D­Dimer, fibrinogen, anti­thrombin III, plasminogen and nitric oxide synthase (NOS) were measured by using ELISA. Both iopamidol and iodixanol treatments deceased cell viability and increased apoptosis of HUVEC and H5V cells, along with downregulated NOS and ABCG1. The injection of iopamidol or iodixanol into rats changed the endothelium­related plasma levels of biomarkers, including endothelin, von Willebrand factor, tissue type plasminogen activator, plasminogen activator inhibitor, D­Dimer, fibrinogen and anti­thrombin III. However, endothelia isolated from rat abdominal aorta in the iodixanol group retained their normal structure, whereas endothelial structure in the iopamidol group was injured and disrupted. The findings in the present study suggested that both hypotonic and isotonic CMs may lead to endothelial dysfunction and thrombin and fibrinolytic system disorder. However, hypotonic CMs may be more toxic than isotonic CMs. Therefore, additional cautions should be taken when selecting hypotonic CMs and their dosages during cardioangiography.


Assuntos
Meios de Contraste/toxicidade , Células Endoteliais da Veia Umbilical Humana/metabolismo , Soluções Hipotônicas/toxicidade , Soluções Isotônicas/toxicidade , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Biomarcadores/metabolismo , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Endotelinas/metabolismo , Fibrinólise , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Iopamidol/toxicidade , Óxido Nítrico Sintase/metabolismo , Ratos Wistar , Fatores de Risco , Trombina/metabolismo , Trombose/metabolismo , Trombose/patologia , Ácidos Tri-Iodobenzoicos/toxicidade
3.
Eur J Pharm Sci ; 57: 60-7, 2014 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-24239995

RESUMO

Microdialysis sampling is a commonly used technique for collecting solutes from the extracellular space of tissues in laboratory animals and humans. Large molecular weight solutes can be collected using high molecular weight cutoff (MWCO) membranes (100kDa or greater). High MWCO membranes require addition of high molecular weight dextrans or albumin to the perfusion fluid to prevent fluid loss via ultrafiltration. While these perfusion fluid additives are commonly used during microdialysis sampling, the tissue response to the loss of these compounds across the membrane is poorly understood. Tissue reactions to implanted microdialysis sampling probes containing different microdialysis perfusion fluids were compared over a 7-day time period in rats. The base perfusion fluid was Ringer's solution supplemented with either bovine serum albumin (BSA), rat serum albumin (RSA), Dextran-70, or Dextran-500. A significant inflammatory response to Dextran-70 was observed. No differences in the tissue response between BSA and RSA were observed. Among these agents, the BSA, RSA, and Dextran-500 produced a significantly reduced inflammatory response compared to the Dextran-70. This work demonstrates that use of Dextran-70 in microdialysis sampling perfusion fluids should be eliminated and replaced with Dextran-500 or other alternatives.


Assuntos
Soluções para Diálise/toxicidade , Reação a Corpo Estranho/etiologia , Microdiálise/efeitos adversos , Tela Subcutânea/efeitos dos fármacos , Animais , Dextranos/metabolismo , Dextranos/toxicidade , Soluções para Diálise/metabolismo , Desenho de Equipamento , Reação a Corpo Estranho/metabolismo , Soluções Isotônicas/metabolismo , Soluções Isotônicas/toxicidade , Masculino , Microdiálise/instrumentação , Microdiálise/métodos , Peso Molecular , Ratos Sprague-Dawley , Solução de Ringer , Fatores de Risco , Soroalbumina Bovina/metabolismo , Soroalbumina Bovina/toxicidade , Tela Subcutânea/metabolismo , Fatores de Tempo
4.
J Surg Res ; 187(2): 587-95, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24315526

RESUMO

BACKGROUND: Large-volume, rapid crystalloid infusion may increase endothelial cell damage and induce shear stress, potentially leading to multiple-organ dysfunction syndrome. Limited guideline data for fluid administration are currently available, especially for the aging population. The aim of the present study was to compare the degree of organ damage in conscious aging rats when different resuscitation speeds were used during the treatment of hemorrhagic shock (HS). METHODS: Eighteen aging male Wistar-Kyoto rats were randomly divided into the following three groups: the control group, 30-min rapid resuscitation group, and 12-h slow resuscitation group. To mimic HS, 40% of the total blood volume was withdrawn. Fluid resuscitation (1:3) was given at 30 min after the blood withdrawal. Blood biochemical parameters including glucose, lactic acid, and lactate dehydrogenase (LDH) were measured along with the levels of serum and bronchoalveolar lavage fluid, tumor necrosis factor alpha (TNF-α), and interleukin 10 by enzyme-linked immunosorbent assay. The lungs were examined for pathologic changes, and the injury score at 24 h after HS was calculated. RESULTS: Compared with slow-rate resuscitation, initially rapid and immediate resuscitation significantly increased the serum levels of glucose, LDH, and proinflammatory cytokines (TNF-α and interleukin 10), and bronchoalveolar lavage fluid levels of white blood cells, TNF-α, and LDH as well as produced pathologic changes in the organ. The lung injury scores were higher after induced HS in aging rats. CONCLUSIONS: The slow and continuous (12 h) fluid resuscitation rate ameliorated HS-induced organ damage in conscious aging rats.


Assuntos
Lesão Pulmonar Aguda/etiologia , Hidratação/efeitos adversos , Soluções Isotônicas/toxicidade , Ressuscitação/efeitos adversos , Choque Hemorrágico/terapia , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/patologia , Envelhecimento , Animais , Glicemia/metabolismo , Pressão Sanguínea , Temperatura Corporal , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Soluções Cristaloides , Hidratação/métodos , Interleucina-10/sangue , Soluções Isotônicas/farmacologia , L-Lactato Desidrogenase/sangue , Ácido Láctico/sangue , Masculino , Distribuição Aleatória , Ratos , Ratos Endogâmicos WKY , Ressuscitação/métodos , Choque Hemorrágico/complicações , Fator de Necrose Tumoral alfa/sangue
5.
Shock ; 38(2): 137-45, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22683725

RESUMO

Lactated Ringer (LR) is a widely used resuscitation fluid that is known to mediate beneficial effects on acid-base balance when compared with normal saline. We here compared LR with the more physiological Ringer solution (RS) regarding acid-base status, hemodynamics, survival, and organ injury following fluid resuscitation subsequent to severe hemorrhagic shock. Anesthetized rats were hemorrhaged to a mean arterial blood pressure of 25 to 30 mmHg within 30 min. After 60 min, they were resuscitated with either RS or LR (three times the shed blood volume) or with RS or LR plus blood (shed blood plus twice its volume) within 30 min. Subsequently, the animals were observed for further 150 min. When the rats were resuscitated with pure LR or RS, all animals of the shock/LR group, but only three of eight shock/RS group rats were dead 100 min later (median survival, 50 ± 13.1 vs. 120 ± 14.1 min; P < 0.05). Coadministration of the shed blood with RS or LR increased the survival rates to 100%. In these blood-resuscitated groups, organ injury, especially of the kidney, was diminished by the use of RS compared with LR. Time-matched acid-base parameters were not different in all shock groups until death of the animals or euthanasia at the end of experimental time. We conclude that, in severe hemorrhagic shock, resuscitation with RS leads to an improved outcome compared with resuscitation with LR, regardless whether blood is coadministered or not.


Assuntos
Soluções Isotônicas/toxicidade , Ressuscitação/efeitos adversos , Choque Hemorrágico/terapia , Desequilíbrio Ácido-Base/induzido quimicamente , Injúria Renal Aguda/induzido quimicamente , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Hematócrito , Hemodinâmica/efeitos dos fármacos , Hemoglobinas/metabolismo , Enteropatias/induzido quimicamente , Intestino Delgado/efeitos dos fármacos , Estimativa de Kaplan-Meier , Masculino , Peroxidase/metabolismo , Ratos , Ratos Wistar , Lactato de Ringer , Solução de Ringer , Análise de Sobrevida
6.
Anesth Analg ; 114(2): 371-4, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22025492

RESUMO

Renal failure is a common complication of critically ill patients. Colloids such as hydroxyethyl starch (HES), gelatin, or albumin are regularly used for intravascular volume resuscitation, but there are increasing reports about the nephrotoxic side effects of synthetic colloids in septic patients. Therefore, we investigated the influence of colloids (HES130/0.4 (Voluven®), gelatin (Gelafundin®), human albumin, and the crystalloid Sterofundin® ISO on cell viability of human proximal tubular (HK-2) cells. HK-2 cells were incubated with colloids (0.1%-4%) and with equivalent volumes of the crystalloid solution Sterofundin ISO. After 21 hours, cell viability of HK-2 cells was measured by EZ4U assay (dye XTT). Application of HES130/0.4 decreased cell viability significantly in a concentration-dependent manner (86.80% ± 10.79% by 0.5% HES down to 24.02% ± 4.27% by 4% HES). Human albumin (>1.25%) as well as gelatin (>1%) also showed deleterious effects on HK-2 cells. Interestingly, in lower concentrations, human albumin and the crystalloid solution Sterofundin ISO were cytoprotective in comparison with the NaCl control. In conclusion, synthetic and natural colloids showed a harmful impact on HK-2 cells in higher concentrations without any prior proinflammatory stimulus. HES130/0.4 exhibited the most distinctive harmful impact, whereas the application of crystalloid Sterofundin ISO revealed cytoprotective effects.


Assuntos
Albuminas/toxicidade , Gelatina/toxicidade , Derivados de Hidroxietil Amido/toxicidade , Soluções Isotônicas/toxicidade , Túbulos Renais Proximais/efeitos dos fármacos , Substitutos do Plasma/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Coloides , Soluções Cristaloides , Citoproteção , Relação Dose-Resposta a Droga , Humanos , Túbulos Renais Proximais/patologia , Compostos Orgânicos/toxicidade , Fatores de Tempo
7.
Am J Physiol Heart Circ Physiol ; 296(6): H1926-32, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19411286

RESUMO

Extracorporeal circulation provides critical life support in the face of cardiopulmonary or renal failure, but it also introduces a host of unique morbidities characterized by edema formation, cardiac insufficiency, autonomic dysfunction, and altered vasomotor function. We tested the hypothesis that cyclohexanone (CHX), a solvent used in production of extracorporeal circuits and intravenous (IV) bags, leaches into the contained fluids and can replicate these clinical morbidities. Crystalloid fluid samples from circuits and IV bags were analyzed by gas chromatography-mass spectrometry to provide a range of clinical CHX exposure levels, revealing CHX contamination of sampled fluids (9.63-3,694 microg/l). In vivo rat studies were conducted (n = 49) to investigate the effects of a bolus IV infusion of CHX vs. saline alone on cardiovascular function, baroreflex responsiveness, and edema formation. Cardiovascular function was evaluated by cardiac output, heart rate, stroke volume, vascular resistance, arterial pressure, and ventricular contractility. Baroreflex function was assessed by mean femoral arterial pressure responses to bilateral carotid occlusion. Edema formation was assessed by the ratio of wet to dry organ weights for lungs, liver, kidneys, and skin. CHX infusion led to systemic hypotension; pulmonary hypertension; depressed contractility, heart rate, stroke volume, and cardiac output; and elevated vascular resistance (P < 0.05). Mean arterial pressure responsiveness to carotid occlusion was dampened after CHX infusion (from +17.25 +/- 1.8 to +5.61 +/- 3.2 mmHg; P < 0.05). CHX infusion led to significantly higher wet-to-dry weight ratios vs. saline only (3.8 +/- 0.06 vs. 3.5 +/- 0.05; P < 0.05). CHX can reproduce clinical cardiovascular, neurological, and edema morbidities associated with extracorporeal circulatory treatment.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Cicloexanonas/toxicidade , Circulação Extracorpórea/efeitos adversos , Solventes/toxicidade , Animais , Barorreflexo/efeitos dos fármacos , Doenças Cardiovasculares/fisiopatologia , Soluções Cristaloides , Edema/induzido quimicamente , Edema/fisiopatologia , Cromatografia Gasosa-Espectrometria de Massas , Cardiopatias/induzido quimicamente , Cardiopatias/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/fisiopatologia , Hipotensão/induzido quimicamente , Hipotensão/fisiopatologia , Infusões Intravenosas/efeitos adversos , Soluções Isotônicas/química , Soluções Isotônicas/toxicidade , Masculino , Contração Miocárdica/efeitos dos fármacos , Plásticos/toxicidade , Ratos , Ratos Sprague-Dawley , Volume Sistólico/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos
8.
J Theor Biol ; 251(1): 93-107, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18083194

RESUMO

A mathematical model of erythrocyte lysis in isotonic solution of ammonium chloride is presented in frames of a statistical approach. The model is used to evaluate several parameters of mature erythrocytes (volume, surface area, hemoglobin concentration, number of anionic exchangers on membrane, elasticity and critical tension of membrane) through their sphering and lysis measured by a scanning flow cytometer (SFC). SFC allows measuring the light-scattering pattern (indicatrix) of an individual cell over the angular range from 10 degrees to 60 degrees . Comparison of the experimentally measured and theoretically calculated light scattering patterns allows discrimination of spherical from non-spherical erythrocytes and evaluation of volume and hemoglobin concentration for individual spherical cells. Three different processes were applied for erythrocytes sphering: (1) colloid osmotic lysis in isotonic solution of ammonium chloride, (2) isovolumetric sphering in the presence of sodium dodecyl sulphate and albumin in neutrally buffered isotonic saline, and (3) osmotic fragility test in hypotonic media. For the hemolysis in ammonium chloride, the evolution of distributions of sphered erythrocytes on volume and hemoglobin content was monitored in real-time experiments. The analysis of experimental data was performed in the context of a statistical approach, taking into account that parameters of erythrocytes vary from cell to cell.


Assuntos
Cloreto de Amônio/toxicidade , Eritrócitos/efeitos dos fármacos , Soluções Isotônicas/toxicidade , Modelos Estatísticos , Adulto , Deformação Eritrocítica , Volume de Eritrócitos , Eritrócitos/patologia , Citometria de Fluxo , Hemólise , Humanos , Masculino , Modelos Biológicos , Fragilidade Osmótica
10.
Acta Ophthalmol Scand ; 84(1): 42-6, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16445438

RESUMO

PURPOSE: To investigate the in vitro toxicity of indocyanine green and infracyanine green (ICG) to cultured ARPE19 cells, in particular with respect to the concentration and time dependence of this toxicity. METHODS: ARPE19 cells were grown for at least 1 week past confluence (hyperconfluent cells) before being subjected to challenge with ICG. Cell survival was tested with the MTT assay. RESULTS: When applied in isotonic solutions, ICG in all concentrations (below 5 mg/ml) and at all exposure times tested (2 mins-2 hours) was found not to affect the survival of ARPE19 cells. ARPE19 cultures older than 30 days were more resistant to a 5 mg/ml hypotonic ICG solution than younger cultures. CONCLUSION: When toxicity of ICG was tested in hyperconfluent ARPE19 cultures, these cells were found to be more resistant to the dye than has been previously reported for more immature ARPE19 cells.


Assuntos
Corantes/toxicidade , Verde de Indocianina/toxicidade , Epitélio Pigmentado Ocular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular , Humanos , Soluções Isotônicas/toxicidade , Perfurações Retinianas/cirurgia , Sais de Tetrazólio , Tiazóis , Fatores de Tempo
11.
J Pediatr Surg ; 39(4): 582-6, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15065032

RESUMO

BACKGROUND/PURPOSE: Whole-bowel irrigation (WBI) has been used for different purposes. It has been the preferred method of bowel cleansing before large bowel surgery and colonoscopy. There are some studies about histopathologic alterations in the gastrointestinal system caused by WBI. It was reported that large quantities of bile-stained intraluminal fluid were seen after WBI with lactated Ringer's solution. In light of all these studies, the authors have decided to inspect whether WBI is choleretic and whether the histopathologic findings in the gastrointestinal system are caused by this choleretic effect. METHODS: During the experimental procedures, animals at first were divided into 2 major groups of A and B; A consisted of the animals whose bile was not collected, and B consisted of animals whose bile was collected. Later, these 2 groups were divided into 4 subgroups consisting of 6 animals each. Sham operations were performed on the animals in group SH-A and SH-B. The animals in group saline-A and saline-B were given 0.9% of sodium chloride (isotonic sodium chloride). The animals in group LR-A and LR-B received lactated Ringer's solution. The last group (PEG-A and PEG-B) underwent WBI by using polyethylene glycol solution (PEG). After completing WBI, animals were rested for 4 hours, and at the end of resting time, laparotomy was performed to take biopsy specimens from stomach, small bowel, and large bowel. All of the specimens were evaluated and graded for congestion, edema, and inflammation by the individual blinded pathologist. RESULTS: According to the results, WBI has been shown to affect biliary secretion and to have a choleretic effect (P <.05, Tuckey-Kramer). The choleretic effect has also been shown to be responsible for histopathologic alterations in some groups (P <.05, Tuckey-Kramer). The most severe changes of congestion, edema, and inflammation have been detected in isotonic sodium chloride solutions in all groups. The least alterations have been seen in lactated Ringer's and PEG solutions. CONCLUSIONS: In light of these findings, it might be concluded that the use of WBI can cause different degrees of histopathologic changes in gastrointestinal system depending on the type of solutions. WBI has been shown to have choleretic effect, and it was found that there is a connection between histopathologic changes in gastrointestinal system and choleretic effect of WBI.


Assuntos
Bile/metabolismo , Colo , Sistema Digestório/efeitos dos fármacos , Fígado/metabolismo , Soluções/farmacologia , Animais , Colagogos e Coleréticos/farmacologia , Colagogos e Coleréticos/toxicidade , Colo/efeitos dos fármacos , Sistema Digestório/patologia , Edema/induzido quimicamente , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Gastroenterite/induzido quimicamente , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Soluções Isotônicas/farmacologia , Soluções Isotônicas/toxicidade , Polietilenoglicóis/farmacologia , Polietilenoglicóis/toxicidade , Ratos , Ratos Sprague-Dawley , Lactato de Ringer , Método Simples-Cego , Cloreto de Sódio/farmacologia , Cloreto de Sódio/toxicidade , Soluções/toxicidade , Irrigação Terapêutica/efeitos adversos
12.
Methods Find Exp Clin Pharmacol ; 24(8): 493-6, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12500428

RESUMO

A study of the different volume and infusion rates of a new maintenance fluid, Veen 3G, on the general conditions of rats was investigated during the 14 days after infusion. In Experiment I, 100 ml/kg and 200 ml/kg of Veen 3G were infused at a rate of 300 ml/kg/h in male and female rats. Results were compared with those for Gurunon Ringer solution (GRS) in male and female rats. We observed only transient polyuria in animals administered by each dose of Veen 3G and GRS for 0-15 min after infusion. Necropsy was not observed in any of the animals tested 14 days after infusion. In Experiment II, 200 ml/kg of Veen 3G was infused at rates of 200, 400, 800 and 1600 ml/kg/h in male rats. At 800 and 1600 ml/kg/h, irregular respiration and decrease in movement were observed concomitantly with polyuria. Three out of 4 rats died immediately after the infusion of Veen 3G at a rate of 1600 ml/kg/h, and one rat was still alive 14 days after the infusion. In this experiment, 200 ml/kg Veen 3G was safe when we infused at a rate of less than 400 ml/kg/h in male rats. Since this rate is about 27-80 times higher than that used clinically in maintenance treatment, Veen 3G is suggested to be safe, with the exception of polyuria, in clinical situations at the standard infusion rate (5-15 ml/kg/h).


Assuntos
Eletrólitos/toxicidade , Hidratação/efeitos adversos , Glucose/toxicidade , Poliúria/induzido quimicamente , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Eletrólitos/administração & dosagem , Cor de Olho/efeitos dos fármacos , Feminino , Hidratação/métodos , Glucose/administração & dosagem , Bombas de Infusão/efeitos adversos , Infusões Intravenosas/métodos , Soluções Isotônicas/administração & dosagem , Soluções Isotônicas/toxicidade , Masculino , Dose Máxima Tolerável , Ratos , Ratos Sprague-Dawley , Insuficiência Respiratória/induzido quimicamente , Solução de Ringer , Convulsões/induzido quimicamente
13.
Microvasc Res ; 59(3): 329-37, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10792963

RESUMO

This study was conducted to quantify the effect of systemic Catalase, a hydrogen peroxide scavenger, on villous microcirculation in the inflamed small intestine of the rat. Intestinal inflammation was induced with s.c. application of Indomethacin. Intravital fluorescence microscopy and FITC-labeled erythrocytes were used to quantify erythrocyte velocity and arteriolar diameter in the main arteriole of the villi in the terminal ileum following i.v. application of Catalase in the inflamed intestine, and the blood flow was calculated. Control groups were formed for Ringer's lactate, Catalase and Indomethacin, respectively. We found that villous blood flow was significantly increased in the in the inflamed intestine. Application of Catalase led to a significant decrease in villous perfusion, but had no effect in the control group. The increase in villous blood flow was accompanied by changes in the diameter of the main arteriole. This effect on arteriolar diameter was reversed by i.v. Catalase. Our results provide evidence that systemic application of Indomethacin leads to vasodilatation of the main arteriole of the villus in the rat ileum and hyperemia in the mucosa. Hyperemia and the vascular diameter of the main arteriole were significantly reduced by H(2)O(2)-scavenger Catalase, suggesting that endogenous H(2)O(2) may be one of the mediators of hyperemia in the mucosa in this animal model of intestinal inflammation.


Assuntos
Catalase/farmacologia , Modelos Animais de Doenças , Sequestradores de Radicais Livres/farmacologia , Peróxido de Hidrogênio/metabolismo , Íleo/irrigação sanguínea , Doenças Inflamatórias Intestinais/tratamento farmacológico , Microcirculação/efeitos dos fármacos , Microvilosidades/efeitos dos fármacos , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/toxicidade , Avaliação Pré-Clínica de Medicamentos , Hiperemia/induzido quimicamente , Íleo/ultraestrutura , Indometacina/toxicidade , Doenças Inflamatórias Intestinais/induzido quimicamente , Mucosa Intestinal/efeitos dos fármacos , Soluções Isotônicas/toxicidade , Masculino , Ratos , Ratos Sprague-Dawley , Respiração/efeitos dos fármacos , Lactato de Ringer
14.
Heart Vessels ; 14(1): 38-51, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10543312

RESUMO

We analyzed total Ca handling of the left ventricle (LV) in the mildly failing heart preparation induced by a temporary intracoronary Ca overloading intervention in eight excised and cross-circulated canine hearts. This Ca intervention consisted of interruption of coronary blood perfusion by Ca-free oxygenated Tyrode perfusion for 10 min followed by high-Ca (16mmol/l) oxygenated Tyrode perfusion for 5 min. This intervention decreased the LV contractility index, Emax (end-systolic maximum elastance), by 40% after restoration of the blood cross-circulation. We expected a Ca overload or paradox failing heart resembling the postischemic stunned heart and being characterized by an increased O2 cost of Emax. However, LV O2 consumption under mechanically unloading conditions decreased by 30% from control without increasing the O2 cost of Emax. To obtain a mechanistic view of this failing heart, we investigated cardiac total Ca handling by our integrative analysis method. In this method, we obtained the internal Ca recirculation fraction (RF) from the decay beat constant of the postextrasystolic potentiation following each sporadic spontaneous extrasystole in these failing LVs. We combined the RF with the decreased Emax and the unchanged O2 cost of Emax in our recently developed formula of total Ca handling. We found that these failing LVs had a slightly but significantly increased RF accompanied by either a slightly increased futile Ca cycling or a slightly decreased Ca reactivity of Emax, or both. Any of these three possible changes can account for the unchanged O2 cost of Emax. This result indicates that the present mildly failing heart has not yet fallen into a typical Ca overload or paradox by the temporary Ca overloading intervention.


Assuntos
Cálcio/metabolismo , Insuficiência Cardíaca/metabolismo , Ventrículos do Coração/metabolismo , Miocárdio/metabolismo , Animais , Sítios de Ligação , Gasometria , Cálcio/toxicidade , Modelos Animais de Doenças , Cães , Eletrocardiografia , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/fisiopatologia , Técnicas In Vitro , Soluções Isotônicas/toxicidade , Contração Miocárdica , Consumo de Oxigênio , Perfusão/métodos
15.
Clin Immunol Immunopathol ; 87(3): 248-55, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9646834

RESUMO

Anecdotal evidence links silicone gel breast implants with the development of autoimmune connective tissue disease in women. To investigate whether silicone gel is capable of directly inducing and/or enhancing the development of autoimmune disease, female BALB/cAnPt (BALB/c) and New Zealand Black (NZB) mice were injected subcutaneously with silicone gel, pristane, a nonmetabolizable substance that can cause plasmacytomas in BALB/c and NZB mice, or saline and monitored for the development of glomerulonephritis and autoantibody production. NZB, but not BALB/c, mice spontaneously develop autoantibodies and an autoimmune hemolytic anemia by 12 months of age. Over a period of 10 months, biweekly screening for proteinuria revealed increases in urinary protein in NZB mice that received multiple injections of either silicone gel or pristane. In contrast, urinary protein was unaffected in identically treated BALB/c mice. Although, silicone gel had no effect on serum titers of antierythrocyte antibodies in NZB mice, the hematocrits were significantly decreased. Moreover, silicone gel both increased the concentration of IgM anti-type I collagen antibodies and skewed the immunofluorescent staining pattern of serum autoantibodies on HEp-2 cells. In contrast, silicone gel failed to induce the production of anti-erythrocyte or antinuclear antibodies in BALB/c mice and induced only slight increases in IgG anti-type I collagen antibodies. These results suggest that silicone gel can exacerbate the development of autoimmune disease in autoimmune NZB mice, but fails to induce disease in normal BALB/c mice. This is consistent with several epidemiological studies failing to demonstrate an increase in the incidence of autoimmune disease in women with breast implants. However, because silicone gel was able to exacerbate autoimmune disease in NZB mice, it may play a similar role in the development of autoimmune disease in a small percentage of women who are genetically susceptible to such diseases.


Assuntos
Doenças Autoimunes/induzido quimicamente , Silicones/toxicidade , Animais , Autoanticorpos/biossíntese , Autoanticorpos/sangue , Doenças Autoimunes/imunologia , Doenças Autoimunes/urina , Modelos Animais de Doenças , Feminino , Glomerulonefrite/induzido quimicamente , Glomerulonefrite/imunologia , Glomerulonefrite/urina , Injeções Subcutâneas , Soluções Isotônicas/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NZB , Proteinúria/induzido quimicamente , Proteinúria/urina , Especificidade da Espécie , Terpenos/toxicidade
16.
Perit Dial Int ; 16 Suppl 1: S137-40, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8728180

RESUMO

Data from cell culture experiments indicate that heat sterilization of peritoneal dialysis (PD) fluids produces cytotoxic glucose degradation products. The present vital microscopic study investigated the effects of different sterilization methods on the biocompatibility of PD fluids. Thus, heat-sterilized (commercially obtained and experimentally produced) and filter-sterilized PD fluids (pH = 5.30-5.40; 1.5% glucose) were compared with Tyrode buffer, with respect to the effects on microvascular blood flow velocity and leukocyte adhesion in the rat mesentery. Exteriorization of the mesentery produced a mild inflammation, known from the literature and characterized by the adhesive rolling of leukocytes along venular walls. Superfusion of the mesentery with filter-sterilized PD fluid had no significant effects on leukocyte rolling or flow velocity in venules 25-40 microns in diameter compared with buffer superfusion. Heat-sterilized PD fluid decreased the concentration of rolling leukocytes and increased flow velocity significantly, as compared with buffer and filter-sterilized PD fluid. The results indicate that heat sterilization of PD fluids produces substances that interact with microvascular tone and leukocyte-endothelial adhesion, which hypothetically could impair the acute, granulocyte-mediated defense against bacterial infections.


Assuntos
Soluções para Diálise/toxicidade , Calefação , Teste de Inibição de Aderência Leucocítica , Diálise Peritoneal , Peritônio/irrigação sanguínea , Esterilização/métodos , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Solução Hipertônica de Glucose/toxicidade , Soluções Isotônicas/toxicidade , Masculino , Mesentério/efeitos dos fármacos , Microcirculação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Vênulas/efeitos dos fármacos
17.
Rev. Hosp. Clin. Fac. Med. Univ. Säo Paulo ; 50(3): 136-9, maio-jun. 1995. ilus, tab
Artigo em Inglês | LILACS | ID: lil-159115

RESUMO

Com o intuito de estudar os fenomenos naturais de defesa contra as hemorragias traumaticas, foram estudados 20 camundongos examinando-se histologicamente algumas de suas grandes veias em caso de sangria, sangria+hemodiluicao e controles, apos fixacao em formol...


Assuntos
Animais , Feminino , Camundongos , Choque/induzido quimicamente , Soluções Isotônicas/toxicidade , Camundongos Endogâmicos BALB C/anatomia & histologia , Choque/sangue
19.
Kardiologiia ; 23(7): 51-5, 1983 Jul.
Artigo em Russo | MEDLINE | ID: mdl-6620813

RESUMO

An experimental study on rat hearts has demonstrated that cardioplegic solutions, apart from their protective effect, activate energy-consuming calcium redistribution process. Presented data permit qualitative and quantitative assessment of myocardial changes and a prompt evaluation of arrested heart's functional status.


Assuntos
Parada Cardíaca Induzida , Coração/efeitos dos fármacos , Soluções Isotônicas/toxicidade , Compostos de Potássio , Potássio/toxicidade , Animais , Cálcio/metabolismo , Coração/fisiopatologia , Parada Cardíaca Induzida/efeitos adversos , Potenciais da Membrana/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Ratos , Fatores de Tempo
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