RESUMO
AIM: To examine renal expression of organic anion transporter 5 (Oat5) and sodium-dicarboxylate cotransporter 1 (NaDC1), and excretion of citrate in rats with acute extrahepatic cholestasis. METHODS: Obstructive jaundice was induced in rats by double ligation and division of the common bile duct (BDL group). Controls underwent sham operation that consisted of exposure, but not ligation, of the common bile duct (Sham group). Studies were performed 21 h after surgery. During this period, animals were maintained in metabolic cages in order to collect urine. The urinary volume was determined by gravimetry. The day of the experiment, blood samples were withdrawn and used to measure total and direct bilirubin as indicative parameters of hepatic function. Serum and urine samples were used for biochemical determinations. Immunoblotting for Oat5 and NaDC1 were performed in renal homogenates and brush border membranes from Sham and BDL rats. Immunohistochemistry studies were performed in kidneys from both experimental groups. Total RNA was extracted from rat renal tissue in order to perform reverse transcription polymerase chain reaction. Another set of experimental animals were used to evaluate medullar renal blood flow (mRBF) using fluorescent microspheres. RESULTS: Total and direct bilirubin levels were significantly higher in BDL animals, attesting to the adequacy of biliary obstruction. An important increase in mRBF was determined in BDL group (Sham: 0.53 ± 0.12 mL/min per 100 g body weight vs BDL: 1.58 ± 0.24 mL/min per 100 g body weight, P < 0.05). An increase in the urinary volume was observed in BDL animals. An important decrease in urinary levels of citrate was seen in BDL group. Besides, a decrease in urinary citrate excretion (Sham: 0.53 ± 0.11 g/g creatinine vs BDL: 0.07 ± 0.02 g/g creatinine, P < 0.05) and an increase in urinary excretion of H(+) (Sham: 0.082 ± 0.03 µmol/g creatinine vs BDL: 0.21 ± 0.04 µmol/g creatinine, P < 0.05) were observed in BDL animals. We found upregulations of both proteins Oat5 and NaDC1 in brush border membranes where they are functional. Immunohistochemistry technique corroborated these results for both proteins. No modifications were observed in Oat5 mRNA and in NaDC1 mRNA levels in kidney from BDL group as compared with Sham ones. CONCLUSION: Citrate excretion is decreased in BDL rats, at least in part, because of the higher NaDC1 expression. Using the outward gradient of citrate generated by NaDC1, Oat5 can reabsorb/eliminate different organic anions of pathophysiological importance.
Assuntos
Colestase Extra-Hepática/metabolismo , Transportadores de Ácidos Dicarboxílicos/metabolismo , Icterícia Obstrutiva/metabolismo , Rim/metabolismo , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Simportadores/metabolismo , Animais , Bilirrubina/sangue , Biomarcadores/sangue , Biomarcadores/urina , Colestase Extra-Hepática/sangue , Colestase Extra-Hepática/genética , Colestase Extra-Hepática/urina , Ácido Cítrico/urina , Ducto Colédoco/cirurgia , Transportadores de Ácidos Dicarboxílicos/genética , Modelos Animais de Doenças , Icterícia Obstrutiva/sangue , Icterícia Obstrutiva/genética , Icterícia Obstrutiva/urina , Ligadura , Masculino , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Ratos Wistar , Circulação Renal , Eliminação Renal , Simportadores/genética , Fatores de Tempo , Regulação para CimaRESUMO
Context Cholestasis produces hepatocellular injury, leukocyte infiltration, ductular cells proliferation and fibrosis of liver parenchyma by extracellular matrix replacement. Objective Analyze bile duct ligation effect upon glycosaminoglycans content and matrix metalloproteinase (MMPs) activities. Methods Animals (6-8 weeks; n = 40) were euthanized 2, 7 or 14 days after bile duct ligation or Sham-surgery. Disease evolution was analyzed by body and liver weight, seric direct bilirubin, globulins, gamma glutamyl transpeptidase (GGT), alkaline phosphatase (Alk-P), alanine and aspartate aminotransferases (ALT and AST), tissue myeloperoxidase and MMP-9, pro MMP-2 and MMP-2 activities, histopathology and glycosaminoglycans content. Results Cholestasis caused cellular damage with elevation of globulins, GGT, Alk-P, ALT, AST. There was neutrophil infiltration observed by the increasing of myeloperoxidase activity on 7 (P = 0.0064) and 14 (P = 0.0002) groups which leads to the magnification of tissue injuries. Bile duct ligation increased pro-MMP-2 (P = 0.0667), MMP-2 (P = 0.0003) and MMP-9 (P<0.0001) activities on 14 days indicating matrix remodeling and establishment of inflammatory process. Bile duct ligation animals showed an increasing on dermatan sulfate and/or heparan sulfate content reflecting extracellular matrix production and growing mitosis due to parenchyma depletion. Conclusions Cholestasis led to many changes on rats’ liver parenchyma, as so as on its extracellular matrix, with major alterations on MMPs activities and glycosaminoglycans content. .
Contexto Colestase produz lesão hepatocelular, infiltração leucocitária, proliferação de células ductulares e fibrose do parênquima hepático por matriz extracelular. Objetivo Analisar os efeitos da ligação do ducto biliar sobre conteúdo de glicosaminoglicanos e atividade de metaloproteinases de matriz (MMP). Métodos Animais (6-8 semanas; n = 40) foram eutanasiados 2, 7 ou 14 dias após ligação do ducto biliar ou falsa ligação. A evolução da doença foi analisada por peso corporal e do fígado, concentrações séricas de bilirrubina direta, globulinas, gama glutamil transpeptidase (GGT), fosfatase alcalina (Alk-P), alanina e aspartato aminotransfesases (ALT e AST), alterações teciduais de mieloperoxidase e metaloproteinases (MMP-9, pro MMP-2 e MMP-2), histopatologia e conteúdo de glicosaminoglicanos. Resultados A colestase causou dano celular com elevação dos níveis séricos de globulinas, GGT, Alk-P, ALT e AST. Houve também infiltração leucocitária observada pelo aumento na atividade de mieloperoxidase nos grupos 7 (P = 0,0064) e 14 dias (P = 0,0002) o que leva ao aumento das lesões no tecido. Ligação do ducto biliar aumentou as atividades de pro MMP-2 (P = 0,0677), MMP-2 (P = 0,0003) e MMP-9 (P<0,0001) aos 14 dias indicando remodelamento da matriz e estabelecimento de processo inflamatório. Animais com ligação do ducto biliar mostraram um aumento do conteúdo de dermatam sulfato e/ou heparam sulfato refletindo a produção de matriz extracelular e aumento de mitose devido a depleção do parênquima hepático. Conclusões Colestase causou várias mudanças no parênquima hepático de ratos, bem como em sua matriz extracelular, com importantes alterações na atividade ...
Assuntos
Animais , Masculino , Colestase Extra-Hepática/metabolismo , Matriz Extracelular/química , Glicosaminoglicanos/metabolismo , Metaloproteases/metabolismo , Glicosaminoglicanos/análise , Metaloproteases/análise , Ratos WistarRESUMO
CONTEXT: Cholestasis produces hepatocellular injury, leukocyte infiltration, ductular cells proliferation and fibrosis of liver parenchyma by extracellular matrix replacement. OBJECTIVE: Analyze bile duct ligation effect upon glycosaminoglycans content and matrix metalloproteinase (MMPs) activities. METHODS: Animals (6-8 weeks; n = 40) were euthanized 2, 7 or 14 days after bile duct ligation or Sham-surgery. Disease evolution was analyzed by body and liver weight, seric direct bilirubin, globulins, gamma glutamyl transpeptidase (GGT), alkaline phosphatase (Alk-P), alanine and aspartate aminotransferases (ALT and AST), tissue myeloperoxidase and MMP-9, pro MMP-2 and MMP-2 activities, histopathology and glycosaminoglycans content. RESULTS: Cholestasis caused cellular damage with elevation of globulins, GGT, Alk-P, ALT, AST. There was neutrophil infiltration observed by the increasing of myeloperoxidase activity on 7 (P = 0.0064) and 14 (P = 0.0002) groups which leads to the magnification of tissue injuries. Bile duct ligation increased pro-MMP-2 (P = 0.0667), MMP-2 (P = 0.0003) and MMP-9 (P<0.0001) activities on 14 days indicating matrix remodeling and establishment of inflammatory process. Bile duct ligation animals showed an increasing on dermatan sulfate and/or heparan sulfate content reflecting extracellular matrix production and growing mitosis due to parenchyma depletion. CONCLUSIONS: Cholestasis led to many changes on rats' liver parenchyma, as so as on its extracellular matrix, with major alterations on MMPs activities and glycosaminoglycans content.
Assuntos
Colestase Extra-Hepática/metabolismo , Matriz Extracelular/química , Glicosaminoglicanos/metabolismo , Metaloproteases/metabolismo , Animais , Glicosaminoglicanos/análise , Masculino , Metaloproteases/análise , Ratos WistarRESUMO
Obstructive jaundice occurs in patients suffering from cholelithiasis and from neoplasms affecting the pancreas and the common bile duct. The absorption, distribution and elimination of drugs are impaired during this pathology. Prolonged cholestasis may alter both liver and kidney function. Lactam antibiotics, diuretics, non-steroidal anti-inflammatory drugs, several antiviral drugs as well as endogenous compounds are classified as organic anions. The hepatic and renal organic anion transport pathways play a key role in the pharmacokinetics of these compounds. It has been demonstrated that acute extrahepatic cholestasis is associated with increased renal elimination of organic anions. The present work describes the molecular mechanisms involved in the regulation of the expression and function of the renal and hepatic organic anion transporters in extrahepatic cholestasis, such as multidrug resistance-associated protein 2, organic anion transporting polypeptide 1, organic anion transporter 3, bilitranslocase, bromosulfophthalein/bilirubin binding protein, organic anion transporter 1 and sodium dependent bile salt transporter. The modulation in the expression of renal organic anion transporters constitutes a compensatory mechanism to overcome the hepatic dysfunction in the elimination of organic anions.
Assuntos
Ácidos e Sais Biliares/metabolismo , Colestase Extra-Hepática/metabolismo , Icterícia Obstrutiva/metabolismo , Rim/metabolismo , Fígado/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Adaptação Fisiológica , Animais , Transporte Biológico , Humanos , Preparações Farmacêuticas/metabolismo , FarmacocinéticaRESUMO
PURPOSE: To study the influence of glutamine on functional and morphological changes of liver in the extrahepatic biliary obstruction through an experimental model in rats. METHODS: Seventy Wistar rats were divided into four groups: control (group C) fictitious operation, (group FO), submitted to laparotomy with handling of bile ducts, but without hepatic duct ligation, (group EBO) submitted to laparotomy and hepatic duct ligation, one of them submitted to supplementation with glutamine 2% (group G). The control group consisted of 6 animals. The animals from groups FO, EBO and G were divided into three groups consisting of 6 animals each, being sacrificed at 7, 14 and 21 days after operation, respectively. Blood samples were collected for biochemical analysis and a fragment of liver tissue was collected from the middle lobe for histological analysis. RESULTS: Both for biochemical analysis (BT, aspartate and alanine aminotransferase AST, ALT and alkaline phosphatase FAL) and for histopathological changes (fibrosis, portal inflammation, parenchymal inflammation, hepatocytic changes and duct proliferation), no statistical difference between groups submitted to extrahepatic biliary obstruction (EBO) with and without treatment with glutamine (G) was observed. CONCLUSION: Glutamine supplementation did not alter the prognosis of liver enzymes and histopathological changes in animals submitted to extrahepatic biliary obstruction.
Assuntos
Ductos Biliares Extra-Hepáticos/patologia , Colestase Extra-Hepática/patologia , Glutamina/administração & dosagem , Fígado/patologia , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Ductos Biliares Extra-Hepáticos/efeitos dos fármacos , Ductos Biliares Extra-Hepáticos/enzimologia , Ductos Biliares Extra-Hepáticos/fisiopatologia , Colestase Extra-Hepática/metabolismo , Colestase Extra-Hepática/fisiopatologia , Modelos Animais de Doenças , Nutrição Enteral/métodos , Ducto Hepático Comum , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/fisiopatologia , Masculino , Complicações Pós-Operatórias/prevenção & controle , Ratos , Ratos WistarRESUMO
PURPOSE: To study the influence of glutamine on functional and morphological changes of liver in the extrahepatic biliary obstruction through an experimental model in rats. METHODS: Seventy Wistar rats were divided into four groups: control (group C) fictitious operation, (group FO), submitted to laparotomy with handling of bile ducts, but without hepatic duct ligation, (group EBO) submitted to laparotomy and hepatic duct ligation, one of them submitted to supplementation with glutamine 2 percent (group G). The control group consisted of 6 animals. The animals from groups FO, EBO and G were divided into three groups consisting of 6 animals each, being sacrificed at 7, 14 and 21 days after operation, respectively. Blood samples were collected for biochemical analysis and a fragment of liver tissue was collected from the middle lobe for histological analysis. RESULTS: Both for biochemical analysis (BT, aspartate and alanine aminotransferase AST, ALT and alkaline phosphatase FAL) and for histopathological changes (fibrosis, portal inflammation, parenchymal inflammation, hepatocytic changes and duct proliferation), no statistical difference between groups submitted to extrahepatic biliary obstruction (EBO) with and without treatment with glutamine (G) was observed. CONCLUSION: Glutamine supplementation did not alter the prognosis of liver enzymes and histopathological changes in animals submitted to extrahepatic biliary obstruction.
OBJETIVO: Estudar a influência da glutamina em alterações funcionais e morfológicas do fígado na obstrução biliar extra-hepática por meio de um modelo experimental desenvolvido em ratos. MÉTODOS: Setenta ratos Wistar distribuídos em quatro grupos: controle (grupo C); operação fictícia (grupo OF), submetido à laparotomia com manuseio das vias biliares, mas sem ligadura do ducto hepático; (grupo OBE), submetido à laparotomia exploradora e ligadura do ducto hepático, sendo um deles submetido à suplementação com glutamina a 2 por cento (grupo G). O grupo controle era composto por seis animais. Os animais dos grupos OF, OBE e G foram divididos em três grupos compostos por seis animais cada e que foram sacrificados no 7°, 14° e 21° dias após a operação, respectivamente. Foi colhido sangue para análise bioquímica e um fragmento de tecido hepático do lobo médio para estudo histológico. RESULTADOS: Tanto em relação à analise bioquímica (BT, aspartate and alanine aminotransferase AST, ALT e FAL) quanto em relação às alterações histopatológicas (fibrose, inflamação portal, inflamação parenquimatosa, alterações hepatocíticas e proliferação de ducto), não houve diferença estatística entre os grupos submetido a obstrução biliar extra-hepática sem (OBE) e com tratamento com glutamina (G). CONCLUSÃO: A suplementação com glutamina não alterou o prognóstico em relação às enzimas hepáticas e alterações histopatológicas nos animais submetidos à obstrução biliar extra-hepática.
Assuntos
Animais , Masculino , Ratos , Ductos Biliares Extra-Hepáticos/patologia , Colestase Extra-Hepática/patologia , Glutamina/administração & dosagem , Fígado/patologia , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Ductos Biliares Extra-Hepáticos/efeitos dos fármacos , Ductos Biliares Extra-Hepáticos/enzimologia , Ductos Biliares Extra-Hepáticos/fisiopatologia , Colestase Extra-Hepática/metabolismo , Colestase Extra-Hepática/fisiopatologia , Modelos Animais de Doenças , Nutrição Enteral/métodos , Ducto Hepático Comum , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/fisiopatologia , Complicações Pós-Operatórias/prevenção & controle , Ratos WistarRESUMO
The pathophysiology of hepatic osteodystrophy (HO) remains poorly understood. Our aim was to evaluate bone histomorphometry, biomechanical properties, and the role of the growth hormone (GH)/insulin-like growth factor-I (IGF-I) system in the onset of this disorder. Forty-six male Wistar rats were divided into two groups: sham-operated (SO, n = 23) and bile duct-ligated (BDL, n = 23). Rats were killed on day 30 postoperatively. Immunohistochemical expression of IGF-I and GH receptor was determined in liver tissue and in the proximal growth plate cartilage of the left tibia. Histomorphometric analysis was performed in the right tibia, and the right femur was used for biomechanical analysis. The maximal force at fracture and the stiffness of the mid-shaft femur were, respectively, 53% and 24% lower in BDL compared to SO. Histomorphometric measurements showed low cancellous bone volume and decreased cancellous bone connectivity in BDL, compatible with osteoporosis. This group also showed increased mineralization lag time, indicating disturbance in bone mineralization. Serum levels of IGF-I were lower in BDL (basal 1,816 +/- 336 vs. 30 days 1,062 +/- 191 ng/ml, P < 0.0001). BDL also showed higher IGF-I expression in the liver tissue but lower IGF-I and GH receptor expression in growth plate cartilage than SO. Osteoporosis is the most important feature of HO; BDL rats show striking signs of reduced bone volume and decreased bone strength, as early as after 1 month of cholestasis. The endocrine and autocrine-paracrine IGF-I systems are deeply affected by cholestasis. Further studies will be necessary to establish their role in the pathogenesis of HO.
Assuntos
Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/patologia , Colestase Extra-Hepática/complicações , Hepatopatias/etiologia , Hepatopatias/patologia , Animais , Colestase Extra-Hepática/metabolismo , Modelos Animais de Doenças , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos , Ratos Wistar , Tíbia/metabolismo , Tíbia/patologiaRESUMO
The kidneys and liver are the major routes for organic anion elimination. We have recently shown that acute obstructive jaundice is associated with increased systemic and renal elimination of two organic anions, p-aminohippurate and furosemide, principally excreted through urine. This study examined probable adaptive mechanisms involved in renal elimination of bromosulfophthalein (BSP), a prototypical organic anion principally excreted in bile, in rats with acute obstructive jaundice. Male Wistar rats underwent bile duct ligation (BDL rats). Pair-fed sham-operated rats served as controls. BSP renal clearance was performed by conventional techniques. Renal organic anion-transporting polypeptide 1 (Oatp1) expression was evaluated by immunoblotting and IHC. Excreted, filtered, and secreted loads of BSP were all higher in BDL rats compared with Sham rats. The higher BSP filtered load resulted from the increase in plasma BSP concentration in BDL rats, because glomerular filtration rate showed no difference with the Sham group. The increase in the secreted load might be explained by the higher expression of Oatp1 observed in apical membranes from kidneys of BDL animals. This likely adaptation to hepatic injury, specifically in biliary components elimination, might explain, at least in part, the huge increase in BSP renal excretion observed in this experimental model.
Assuntos
Colestase Extra-Hepática/metabolismo , Icterícia Obstrutiva/metabolismo , Rim/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/fisiologia , Sulfobromoftaleína/farmacocinética , Doença Aguda , Animais , Ânions , Immunoblotting , Imuno-Histoquímica , Masculino , Microvilosidades/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/biossíntese , Ratos , Ratos WistarRESUMO
Bilioduodenal and biliojejunal anastomoses are effective for the treatment of biliary obstruction. The objective of this study was to compare the effects of these anastomoses on hepatobiliary excretion and enterobiliary reflux. Enterobiliary reflux and biliary excretion were evaluated respectively after oral administration of technetium ((99m)Tc) in combination with sodium phytate and intravenous infusion of (99m)Tc with diisopropyl-iminodiacetic acid. Enterobiliary reflux occurred to an equal degree in the bilioduodenal and biliojejunal groups. Maximum hepatic activity time (T(max)) and radiotracer clearance half-time (T(1/2)) were similar in both groups. However, when compared with that found for the sham-operated group, T(max), and T(1/2) were higher in the biliojejunal group (P = 0.02 and P = 0.01, respectively). Histopathological analysis showed marked reduction in ductal proliferation in both groups. These data undermine the theoretical advantages attributed to biliojejunal anastomosis and further the understanding of the pathophysiology of cholangitis that occurs even with patent anastomosis.
Assuntos
Ductos Biliares Extra-Hepáticos , Refluxo Biliar/etiologia , Colestase Extra-Hepática/metabolismo , Colestase Extra-Hepática/cirurgia , Duodeno/cirurgia , Jejuno/cirurgia , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Animais , Colangite/etiologia , Masculino , Ratos , Ratos WistarRESUMO
BACKGROUD: Chronic liver diseases in childhood often cause undernutrition and growth failure. To our knowledge, growth parameters in infants with neonatal cholestasis are not available AIM: To evaluate the nutritional status and growth pattern in infants with intrahepatic cholestasis and extrahepatic cholestasis. PATIENTS AND METHODS: One hundred forty-four patients with neonatal cholestasis were followed up at the Pediatric Gastroenterology Service of the Teaching Hospital, State University of Campinas, Campinas, SP, Brazil, in a 23-year period, from 1980 to 2003. The records of these patients were reviewed and patients were classified into two groups, according to their anatomical diagnosis: patients with intrahepatic cholestasis - group 1, and patients with extrahepatic cholestasis - group 2. Records of weight and height measurements were collected at 4 age stages of growth, in the first year of life: 1) from the time of the first medical visit to the age of 4 months (T1); 2) from the 5th to the 7th month (T2); 3) from the 8th to the 10th month (T3); and 4) from the 11th to the 13th month (T4). The weight-by-age and height-by-age Z-scores were calculated for each patient at each stage. In order for the patient to be included in the study it was necessary to have the weight and/or height measurements at the 4 stages. Analyses of variance and Tukey's tests were used for statistical analysis. Repeated measurement analyses of variance of the weight-by-age Z-score were performed in a 60-patient sample, including 29 patients from group 1 and 31 patients from group 2. The height-by-age data of 33 patients were recorded, 15 from group 1 and 18 from group 2 RESULTS: The mean weight-by-age Z-scores of group 1 patients at the 4 age stages were: T1=-1.54; T2=-1.40; T3=-0.94; T4=-0.78. There was a significant difference between T2 X T3 and T1 X T4. The weight-by-age Z-scores for group 2 patients were :T1=-1.04; T2=-1.67; T3=-1.93 and T4=-1.77, with a...
RACIONAL: As doenças hepáticas crônicas na infância freqüentemente levam à desnutrição e ao déficit de crescimento, sem haver referência de um padrão definido para colestase neonatal OBJETIVO: Avaliar o estado nutricional e o padrão de crescimento em crianças com colestase intra-hepática e colestase extra-hepática MATERIAL E MÉTODOS: Foram revistos os prontuários de 144 pacientes com colestase neonatal atendidos no Serviço de Gastroenterologia Pediátrica do Hospital de Clínicas da UNICAMP, Campinas, SP, durante o período de 1980 a 2003 e de acordo com o diagnóstico anatômico, classificados em dois grupos: grupo 1, pacientes com colestase intra-hepática e grupo 2, com colestase extra-hepática. Os valores de peso e estatura foram obtidos em quatro momentos: 1°) Na primeira consulta realizada até o 4° mês de vida, 2°) entre o 5° e o 7° mês, 3°) entre o 8° e o 10° mês e 4°) entre o 11° e 13° mês. Para cada paciente foi realizado o cálculo do Z-escore em relação ao peso para a idade e estatura para a idade nos momentos 1 a 4. Para o paciente ser incluído no estudo, era necessário ter as medidas de peso e/ou estatura nos quatro estágios. A estatística empregada foi a análise de variância e o teste de Tukey. Para análise de variância com medidas repetidas quanto ao escore-Z de peso para a idade, a amostra utilizada foi de 60 pacientes, sendo 29 do grupo 1 e 31 do grupo 2. Para estatura, a amostra utilizada foi de 33 pacientes, sendo 15 do grupo 1 e 18 do grupo 2. RESULTADOS: As médias dos escores-Z de peso para a idade nos quatro momentos da avaliação para os pacientes do grupo 1 foram: T1 =-1.54; T2 = -1.40; T3 = -0,94; T4 = -0.78, havendo diferença significante entre T2×T3 e entre T1×T4. Para os pacientes do grupo 2 foram: T1 = -1.04; T2 = -1.67; T3 =-1.93 e T4 = -1.77, havendo diferença significante entre T1×T2 e T1×T4. Houve também diferença significante entre as médias dos escores-Z de peso para a idade entre o grupo...
Assuntos
Humanos , Lactente , Recém-Nascido , Tamanho Corporal/fisiologia , Desenvolvimento Infantil/fisiologia , Colestase Extra-Hepática/fisiopatologia , Colestase Intra-Hepática/fisiopatologia , Transtornos do Crescimento/fisiopatologia , Estado Nutricional/fisiologia , Análise de Variância , Antropometria , Estatura/fisiologia , Peso Corporal/fisiologia , Colestase Extra-Hepática/metabolismo , Colestase Intra-Hepática/metabolismo , Transtornos do Crescimento/metabolismo , Icterícia Neonatal/fisiopatologia , Desnutrição/metabolismo , Desnutrição/fisiopatologia , Triglicerídeos/farmacocinéticaRESUMO
Renal function in the course of obstructive jaundice has been the subject of great interest; however, little is known about the expression of renal organic anion transporters. The objective of this work was to study, in rats with acute extrahepatic cholestasis, the cortical renal expression of the organic anion transporter 1 (OAT1) and the organic anion transporter 3 (OAT3), in association with the pharmacokinetics and renal excretion of furosemide (FS). Male Wistar rats underwent bile duct ligation (BDL rats). Pair-fed sham-operated rats served as controls. All studies were carried out 21 hours after surgery. Rats were anesthetized and the pharmacokinetic parameters of FS and the renal elimination of FS were determined. Afterwards, the kidneys were excised and processed for immunoblot (basolateral membrane and renal homogenates) or immunocytochemical (light microscopic and confocal immunofluorescence microscopic analysis) techniques. The systemic and renal clearance of FS as well as the excreted and secreted load of FS increased in BDL rats. In kidneys from BDL rats, immunoblotting showed a significant increase in the abundance of both OAT1 and OAT3 in homogenates from renal cortex. In basolateral membranes from kidney cortex of BDL rats, OATI abundance was also increased and OAT3 abundance was not modified. Immunocytochemical techniques confirmed these results. In conclusion, acute obstructive jaundice is associated with an upregulation of OAT1 and OAT3, which might explain, at least in part, the increased systemic and renal elimination of FS.
Assuntos
Colestase Extra-Hepática/metabolismo , Córtex Renal/metabolismo , Proteína 1 Transportadora de Ânions Orgânicos/biossíntese , Transportadores de Ânions Orgânicos Sódio-Independentes/biossíntese , Doença Aguda , Animais , Masculino , Ratos , Ratos WistarRESUMO
BACKGROUND: [corrected] Chronic liver diseases in childhood often cause undernutrition and growth failure. To our knowledge, growth parameters in infants with neonatal cholestasis are not available AIM: To evaluate the nutritional status and growth pattern in infants with intrahepatic cholestasis and extrahepatic cholestasis. PATIENTS AND METHODS: One hundred forty-four patients with neonatal cholestasis were followed up at the Pediatric Gastroenterology Service of the Teaching Hospital, State University of Campinas, Campinas, SP, Brazil, in a 23-year period, from 1980 to 2003. The records of these patients were reviewed and patients were classified into two groups, according to their anatomical diagnosis: patients with intrahepatic cholestasis - group 1, and patients with extrahepatic cholestasis - group 2. Records of weight and height measurements were collected at 4 age stages of growth, in the first year of life: 1) from the time of the first medical visit to the age of 4 months (T1); 2) from the 5th to the 7th month (T2); 3) from the 8th to the 10th month (T3); and 4) from the 11th to the 13th month (T4). The weight-by-age and height-by-age Z-scores were calculated for each patient at each stage. In order for the patient to be included in the study it was necessary to have the weight and/or height measurements at the 4 stages. Analyses of variance and Tukey's tests were used for statistical analysis. Repeated measurement analyses of variance of the weight-by-age Z-score were performed in a 60-patient sample, including 29 patients from group 1 and 31 patients from group 2. The height-by-age data of 33 patients were recorded, 15 from group 1 and 18 from group 2 RESULTS: The mean weight-by-age Z-scores of group 1 patients at the 4 age stages were: T1=-1.54; T2=-1.40; T3=-0.94; T4=-0.78. There was a significant difference between T2 X T3 and T1 X T4. The weight-by-age Z-scores for group 2 patients were :T1=-1.04; T2=-1.67; T3=-1.93 and T4=-1.77, with a significant difference between T1 X T2 and T1 X T4. The mean weight-by-age Z-scores also showed a significant difference between group 1 and group 2 at stages T3 and T4. The mean height-by-age Z-scores at the four stages in group 1 were: T1=-1.27; T2=-1.16; T3=-0.92 and T4=-0.22, with a significant difference between T3XT4 and T1XT4. The scores for group 2 patients were: T1=-0.93; T2=-1.89; T3=-2.26 and T4=-2.03, with a significant difference between T1XT2 and T1XT4. The mean height-by-age Z-scores also showed a significant difference between group 1 and group 2 at T3 and T4 CONCLUSION: The weight and height differences between the groups became significant from the 3rd measurement onward, with the most substantial deficit found in the extrahepatic group. In this group, there is evidence that the onset of weight and height deficit occurs between the first and second evaluation stages.
Assuntos
Tamanho Corporal/fisiologia , Desenvolvimento Infantil/fisiologia , Colestase Extra-Hepática/fisiopatologia , Colestase Intra-Hepática/fisiopatologia , Transtornos do Crescimento/fisiopatologia , Estado Nutricional/fisiologia , Análise de Variância , Antropometria , Estatura/fisiologia , Peso Corporal/fisiologia , Colestase Extra-Hepática/metabolismo , Colestase Intra-Hepática/metabolismo , Transtornos do Crescimento/metabolismo , Humanos , Lactente , Recém-Nascido , Icterícia Neonatal/fisiopatologia , Desnutrição/metabolismo , Desnutrição/fisiopatologia , Triglicerídeos/farmacocinéticaRESUMO
Hepatocytes express the water channel aquaporin-8 (AQP8), which is mainly localized in intracellular vesicles, and its adenosine 3',5'-cyclic monophosphate (cAMP)-induced translocation to the plasma membrane facilitates osmotic water movement during canalicular bile secretion. Thus, defective expression of AQP8 may be associated with secretory dysfunction of hepatocytes caused by extrahepatic cholestasis. We studied the effect of 1, 3, and 7 days of bile duct ligation (BDL) on protein expression, subcellular localization, and messenger RNA (mRNA) levels of AQP8; this was determined in rat livers by immunoblotting in subcellular membranes, light immunohistochemistry, immunogold electron microscopy, and Northern blotting. One day of BDL did not affect expression or subcellular localization of AQP8. Three days of BDL reduced the amount of intracellular AQP8 (75%; P <.001) without affecting its plasma membrane expression. Seven days after BDL, AQP8 was markedly decreased in intracellular (67%; P <.05) and plasma (56%; P <.05) membranes. Dibutyryl cAMP failed to increase AQP8 in plasma membranes from liver slices, suggesting a defective translocation of AQP8 in 7-day BDL rats. Immunohistochemistry and immunoelectron microscopy in liver sections confirmed the BDL-induced decreased expression of hepatocyte AQP8 in intracellular vesicles and canalicular membranes. AQP8 mRNA expression was unaffected by 1-day BDL but was significantly increased by about 200% in 3- and 7-day BDL rats, indicating a posttranscriptional mechanism for protein level reduction. In conclusion, BDL-induced extrahepatic cholestasis caused posttranscriptional down-regulation of hepatocyte AQP8 protein expression. Defective expression of AQP8 water channels may contribute to bile secretory dysfunction of cholestatic hepatocytes.
Assuntos
Aquaporinas/metabolismo , Colestase Extra-Hepática/metabolismo , Hepatócitos/metabolismo , Canais Iônicos , Animais , Aquaporinas/genética , Ductos Biliares , Colestase Extra-Hepática/fisiopatologia , Regulação para Baixo , Expressão Gênica , Ligadura , Fígado/citologia , Fígado/metabolismo , Masculino , RNA Mensageiro/análise , Ratos , Ratos Wistar , Frações Subcelulares/metabolismoRESUMO
Hepatic uptake and biliary excretion of bile salts and non-bile salt organic anions is mediated by specific transport proteins located at the basolateral and canalicular membranes of hepatocytes. Several hepatobiliary transport systems have been identified and cloned over the past years. This development has facilitated molecular biological and genetic analyses of these transporters in experimental cholestasis and human cholestatic liver diseases. Evidence now exists that decreased or even absent expression of hepatobiliary transport systems may explain impaired transport function resulting in hyperbilirubinemia and cholestasis. This review summarizes the molecular defects in hepatocellular membrane transporters associated with hereditary and acquired forms of cholestatic liver diseases. The increasing information on the molecular regulation of hepatobiliary transport systems should bring new insights into the pathophysiology and treatment of human cholestatic liver diseases.
Assuntos
Colestase Intra-Hepática/metabolismo , Animais , Doenças Autoimunes/complicações , Bile/química , Ácidos e Sais Biliares/metabolismo , Ductos Biliares Intra-Hepáticos/citologia , Doença Hepática Induzida por Substâncias e Drogas/complicações , Colestase Extra-Hepática/metabolismo , Colestase Intra-Hepática/complicações , Colestase Intra-Hepática/etiologia , Colestase Intra-Hepática/fisiopatologia , Colesterol/análise , Estradiol/efeitos adversos , Homeostase , Humanos , Sepse/complicaçõesRESUMO
Excretion of lipophilic cationic toxic compounds from the interior of the hepatocyte to the bile is mediated by P-Glycoprotein. It is an integral protein located in the bile canaliculi. The present work study the hepatic expression of P-Glycoprotein in different models of experimental liver disease: Acute paracetamol intoxication, extrahepatic cholestasis and cholestasis followed by acute paracetamol intoxication. mRNA was isolated from liver tissue, and the expression of Pg-p was assessed by Northern blot. It is concluded that the hepatic expression of mdr1b is increased in the experimental liver diseases when compared to controls. On the other hand, mdr2 expression was similar between the different groups (AU)
Assuntos
Animais , Masculino , Ratos , Acetaminofen/toxicidade , Analgésicos não Narcóticos/toxicidade , Colestase Extra-Hepática/induzido quimicamente , Regulação da Expressão Gênica , Genes MDR/genética , Hepatopatias/induzido quimicamente , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Acetaminofen/metabolismo , Doença Aguda , Analgésicos não Narcóticos/metabolismo , Bile/metabolismo , Colestase Extra-Hepática/metabolismo , Northern Blotting , Proteínas de Transporte/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Genes MDR/efeitos dos fármacos , Hepatócitos , Hepatopatias/metabolismo , Overdose de Drogas , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos WistarRESUMO
Excretion of lipophilic cationic toxic compounds from the interior of the hepatocyte to the bile is mediated by P-Glycoprotein. It is an integral protein located in the bile canaliculi. The present work study the hepatic expression of P-Glycoprotein in different models of experimental liver disease: Acute paracetamol intoxication, extrahepatic cholestasis and cholestasis followed by acute paracetamol intoxication. mRNA was isolated from liver tissue, and the expression of Pg-p was assessed by Northern blot. It is concluded that the hepatic expression of mdr1b is increased in the experimental liver diseases when compared to controls. On the other hand, mdr2 expression was similar between the different groups.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Acetaminofen/toxicidade , Analgésicos não Narcóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas , Colestase Extra-Hepática/induzido quimicamente , Regulação da Expressão Gênica , Genes MDR/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Acetaminofen/metabolismo , Doença Aguda , Analgésicos não Narcóticos/metabolismo , Animais , Bile/metabolismo , Northern Blotting , Proteínas de Transporte/metabolismo , Colestase Extra-Hepática/metabolismo , Modelos Animais de Doenças , Overdose de Drogas , Regulação da Expressão Gênica/efeitos dos fármacos , Genes MDR/efeitos dos fármacos , Hepatócitos , Hepatopatias/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos WistarRESUMO
In this study we analyzed the effect resulting from a short-term (1 h) bile duct obstruction in bile acid-depleted or taurocholate-replenished rats on liver cytochrome P450 enzyme system activity. Rats were depleted of endogenous bile acids and then subjected to a biliary obstruction for 1 h. Some of these depleted-obstructed rats were replenished previously to the obstruction with exogenous taurocholic acid (TC) and the others were treated with the solvent alone. To study the isolated effect of the bile acid, other rats were also previously depleted and then replenished with TC but they were obstructed briefly (20 min). CYP3A2-linked activity was evaluated in vivo with the aminopyrine breath test and in vitro by the measurement of nifedipine oxidase microsomal activity. The results suggested that bile flow suppression per se might inhibit this CYP-linked activity and that bile acid retention is not involved at least as a sole determinant.
Assuntos
Ácidos e Sais Biliares/metabolismo , Colestase Extra-Hepática/metabolismo , Inibidores das Enzimas do Citocromo P-450 , Fígado/metabolismo , Aminopirina , Animais , Ácidos e Sais Biliares/análise , Ductos Biliares/cirurgia , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/análise , Sistema Enzimático do Citocromo P-450/metabolismo , Ligadura , Masculino , Oxigenases de Função Mista/análise , Ratos , Ratos Wistar , Esteroide Hidroxilases/metabolismo , Fatores de TempoRESUMO
Adaptive hepatic changes were investigated in rats with mild stenosis of the common bile duct and in sham-operated controls. The studies were performed 24 h and 7-12 days postoperatively. A continuous intravenous infusion of taurocholic acid at stepwise-increasing rates was performed to explore the responses to bile acid effects. During the infusion, bile flow and the outputs of bile acids, phospholipids, cholesterol, alkaline phosphatase and gamma glutamyl transpeptidase were studied. At the end of the infusion, hepatic morphometric measurements were performed. In other experimental sets, biliary excretions of horseradish peroxidase, a marker of microtubule-dependent vesicular transport in the hepatocyte, and sulphobromophthalein, a well-known organic anion model, were studied. In other rats, bile acid pool size and composition were determined by depletion of bile. The results in rats with mild stenosis maintained for 24 h showed a greater susceptibility to the toxicity of taurocholic acid, as revealed by the abrupt decrement in bile flow at high rates of infusion, and increased outputs of phospholipids and canalicular enzymes. Conversely, rats with mild stenosis maintained for 7-12 days showed decreased bile acid maximum secretory rate and biliary outputs of phospholipids and canalicular enzymes, as well as hepatocyte hypertrophy. These findings may explain the limited hepatic and systemic repercussion of experimental mild stenosis of the common bile duct and help us to understand the early stages of constriction of the common bile duct in man.
Assuntos
Adaptação Fisiológica/fisiologia , Colestase Extra-Hepática/patologia , Doenças do Ducto Colédoco/patologia , Fígado/enzimologia , Fosfatase Alcalina/metabolismo , Animais , Ácidos e Sais Biliares/análise , Ácidos e Sais Biliares/metabolismo , Colestase Extra-Hepática/metabolismo , Doenças do Ducto Colédoco/metabolismo , Constrição Patológica , Peroxidase do Rábano Silvestre/farmacocinética , Concentração de Íons de Hidrogênio , Injeções Intravenosas , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Sulfobromoftaleína/farmacocinética , Ácido Taurocólico/farmacologia , gama-Glutamiltransferase/metabolismoRESUMO
We evaluated 51 tests of 99mTc-DISIDA excretion by the biliary tree in patients with neonatal cholestasis. The aim of the present study was to verify the value of this test in the differentiation of this syndrome, correlating it to the clinical and laboratory data. The case studied were divided into two groups: extrahepatic biliary atresia, 26 patients (50.9%) and no-extrahepatic biliary atresia, 25 patients (49.1%). Analyzing the results, we concluded that this test had 96% sensitivity, 56% specificity, 69% positive predictive value, 93% negative predictive value and 76.5% accuracy. The accuracy of this test was only lower than that of hepatic biopsy. We conclude that the hepatobiliary scintigraphy was very useful in the definition of extrahepatic biliary atresia, with less value in the group of neonatal hepatitis, perhaps due to the delayed referral of the patients, short time of the scintigraphy study or factors related to the etiology of cholestasis itself.
Assuntos
Colestase Extra-Hepática/diagnóstico por imagem , Iminoácidos/metabolismo , Icterícia Neonatal/etiologia , Compostos de Organotecnécio/metabolismo , Colestase Extra-Hepática/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Icterícia Neonatal/diagnóstico , Masculino , Cintilografia , Estudos Retrospectivos , Disofenina Tecnécio Tc 99mRESUMO
Acetaminophen high doses toxicity has been reported in clinical and experimental studies in relation with cytochrome P-450. (Acetaminophen metabolite). Thinking that biliary tract obstructions hould increases drugs toxicity because interferes toxic substances excretion or it modify the activity of P-450 we decided to study acetaminophen toxicity in rats with biliary tract obstruction. Male sprague Dawley rats were used (body weight 250-400 gr) in two groups: Group I control (6 rats) with choledoco bile duct ligated; two doses of saline solution 0.9% Intraperitoneal, 0.2 ml/100 gr. were administrated. Group II (Same surgical intervention) received two doses of acetaminophen (intraperitoneal) solution (400 mg/Kg). This group was divided in two (6 rats each), one of this was sacrificed at 48 h. and the other one at 120 h. after acetaminophen injection. Total, direct and indirect bilirubin, alkaline phosphatase, ALT and AST transaminases, hematology study, liver weight, histological studies of liver and kidney were performed in all rats. High incidence of liver necrosis ans significative transaminases increases were found in group II. Our results were discussed taking account that recent biliary tract obstruction increase acetaminophen toxicity, at a half doses reported in other studies. It is possible that mixed oxidation system activity of cytochrome P-450 was increased in our research.