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1.
Acta Cir Bras ; 39: e390924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324802

RESUMO

PURPOSE: Osteoarthritis (OA) is a degenerative joint disease which is categorized via destruction of joint cartilage and it also affects the various joints, especially knees and hips. Sinomenine active phytoconstituents isolated from the stem of Sinomenium acutum and already proof anti-inflammatory effect against the arthritis model of rodent. In this experimental protocol, we scrutinized the anti-osteoarthritis effect of sinomenine against monosodium iodoacetate (MIA) induced OA in rats. METHODS: MIA (3 mg/50 µL) was used for inducing the OA in the rats, and rats received the oral administration of sinomenine (2.5, 5 and 7.5 mg/kg body weight) up to the end of the experimental study (four weeks). The body and organs weight were estimated. Aggrecan, C-terminal cross-linked telopeptide of type II collagen (CTX-II), glycosaminoglycans (GCGs), monocyte chemoattractant protein-1 (MCP-1), Interferon gamma (IFN-γ), antioxidant, inflammatory cytokines, inflammatory mediators and matrix metalloproteinases (MMP) were analyzed. RESULTS: Sinomenine significantly (P < 0.001) boosted the body weight and reduced the heart weight, but the weight of spleen and kidney remain unchanged. Sinomenine significantly (P < 0.001) reduced the level of nitric oxide, MCP-1 and improved the level of aggrecan, IFN-γ and GCGs. Sinomenine remarkably upregulated the level of glutathione, superoxide dismutase and suppressed the level of malonaldehyde. It effectually modulated the level of inflammatory cytokines and inflammatory mediators and significantly (P < 0.001) reduced the level of MMPs, like MMP-1, 2, 3, 9 and 13. CONCLUSIONS: Sinomenine is a beneficial active agent for the treatment of OA disease.


Assuntos
Cartilagem Articular , Morfinanos , Osteoartrite , Ratos , Animais , Ácido Iodoacético/metabolismo , Ácido Iodoacético/farmacologia , Osteoartrite/metabolismo , Agrecanas/metabolismo , Agrecanas/farmacologia , Modelos Animais de Doenças , Cartilagem Articular/metabolismo , Metaloproteinases da Matriz/metabolismo , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Peso Corporal
2.
Lasers Med Sci ; 37(3): 1687-1698, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34542770

RESUMO

Pain is the most common symptom of osteoarthritis, and spinal glia is known to contribute to this symptom. Therapeutic ultrasound and laser therapy have been used to effectively treat osteoarthritis, with few adverse effects. Thus, this study aimed to investigate the effects of ultrasound and photobiomodulation on the symptoms and evaluate the participation of spinal glia in osteoarthritis-induced nociception in mice. Male Swiss mice were subjected to osteoarthritis induction with a 0.1-mg intra-articular injection of monosodium iodoacetate. Additionally, the mice received chronic ultrasound or photobiomodulation treatment for 21 days or a single treatment at day 14. Nociception was evaluated using von Frey filaments, and osteoarthritis symptoms were assessed by analysis of gait, joint temperature, and knee joint diameter. The role of spinal microglia and astrocytes on nociception was evaluated via an intrathecal injection of minocycline or fluorocitrate, and the spinal release of IL-1ß and TNF-α was assessed by ELISA after chronic treatment with ultrasound or photobiomodulation. Our data showed that both single and chronic treatment with ultrasound or photobiomodulation attenuated the osteoarthritis-induced nociception. No differences in gait, knee joint temperature, or knee joint diameter were found. The intrathecal injection of minocycline and fluorocitrate decreased the osteoarthritis-induced nociception. There was an increase in the spinal levels of TNF-α, which was reverted by chronic ultrasound and laser treatments. These results suggest that osteoarthritis induces nociception and glial activation via spinal release of TNF-α and that the chronic treatment with ultrasound or photobiomodulation decreased nociception and TNF-α release.


Assuntos
Nociceptividade , Osteoartrite , Animais , Modelos Animais de Doenças , Ácido Iodoacético/farmacologia , Masculino , Camundongos , Neuroglia , Osteoartrite/radioterapia , Dor
3.
Int. j. morphol ; 37(4): 1551-1556, Dec. 2019. graf
Artigo em Espanhol | LILACS | ID: biblio-1040168

RESUMO

La inyección con monoiodo acetato de sodio (MIA) es ampliamente utilizada para producir osteoartritis en diversas articulaciones. El objetivo fue describir los daños histológicos provocados por MIA en la articulación humeral de rata. Se inyectó 0,1 mL de mezcla de 0,5 mg de MIA disuelto en 10 mL de solución fisiológica en la articulación humeral izquierda de 21 ratas SpragueDawley. Como control se utilizó la articulación derecha de cada rata. Se realizó la eutanasia a las 4, 8 y 12 semanas post inyección en grupos de 7 ratas. Los miembros mantenidos en formalina tamponada al 10% fueron descalcificados con EDTA por tres meses. Para la evaluación histológica se realizó la inclusión en parafina y se realizaron cortes coronales de 5 µm de espesor, para posterior tinción con azul de toluidina. En el cartílago sano, se observó una superficie lisa sin fisuras, todas las células de las zonas del cartílago se observaron normales. Se observaron cambios en el cartílago articular a partir de las 4 semanas post inyección, los condrocitos de la zona radial hipertróficos con gran producción de proteoglicanos. A las 12 semanas post inyección, se observa un gran deterioro, el espacio articular se ve disminuido, La superficie del cartílago se observa con fisuras y grietas que llegan hasta la zona radial. Las células alrededor de estas fisuras han desaparecido. Se observa una pérdida prominente de proteoglicanos debido a la débil tinción con azul de toluidina. La inyección articular con MIA produce lesiones similares a la OA. La gran ventaja de la OA inducida por MIA, es la facilidad de su aplicación y la rapidez en la progresión de OA.


Injection with monoiode sodium acetate (MIA) is widely used to produce osteoarthritis in various joints. The aim of this work was to describe the histological damage caused by MIA in the rat humeral joint; 0.1 mL of 0.5 mg mixture of MIA dissolved in 10 mL of physiological solution was injected into the left humeral joint of 21 Sprague-Dawley rats. As a control, the right joint of each rat was used. Euthanasia was performed at 4, 8 and 12 weeks post injection in groups of 7 rats. The samples maintained in 10 % buffered formalin were descaled with EDTA for three months. For histological evaluation, paraffin inclusion was performed and 5 µm thick coronal cuts were made for subsequent staining with toluidine blue. In the healthy cartilage, a smooth surface was observed, all cells in the cartilage areas were normal. Changes in articular cartilage were observed after 4 weeks post injection, hypertrophic radial chondrocytes with high proteoglycan production. At 12 weeks post injection, a great deterioration was observed, the articular space was diminished. The surface of the cartilage was observed with fissures and cracks that reach the radial zone. The cells around these fissures have disappeared. A prominent loss of proteoglycans was observed due to weak toluidine blue staining. Joint injection with MIA produced lesions similar to OA. The great advantage of the OA induced by MIA, is the ease of its application and the rapidity in the progression of OA.


Assuntos
Animais , Feminino , Ratos , Osteoartrite/induzido quimicamente , Articulação do Ombro/patologia , Ácido Iodoacético/farmacologia , Osteoartrite/patologia , Articulação do Ombro/efeitos dos fármacos , Cartilagem Articular/patologia , Ratos Sprague-Dawley , Modelos Animais de Doenças , Úmero/patologia
4.
Biochem Mol Biol Educ ; 46(5): 502-515, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30281891

RESUMO

Metabolic control analysis (MCA) is a promising approach in biochemistry aimed at understanding processes in a quantitative fashion. Here the contribution of enzymes and transporters to the control of a given pathway flux and metabolite concentrations is determined and expressed quantitatively by means of numerical coefficients. Metabolic flux can be influenced by a wide variety of modulators acting on one or more metabolic steps along the pathway. We describe a laboratory exercise to study metabolic regulation of human erythrocytes (RBCs). Within the framework of MCA, students use these cells to determine the sensitivity of the glycolytic flux to two inhibitors (iodoacetic acid: IA, and iodoacetamide: IAA) known to act on the enzyme glyceraldehyde-3-phosphate-dehydrogenase. Glycolytic flux was estimated by determining the concentration of extracellular lactate, the end product of RBC glycolysis. A low-cost colorimetric assay was implemented, that takes advantage of the straightforward quantification of the absorbance signal from the photographic image of the multi-well plate taken with a standard digital camera. Students estimate flux response coefficients for each inhibitor by fitting an empirical function to the experimental data, followed by analytical derivation of this function. IA and IAA exhibit qualitatively different patterns, which are thoroughly analyzed in terms of the physicochemical properties influencing their action on the target enzyme. IA causes highest glycolytic flux inhibition at lower concentration than IAA. This work illustrates the feasibility of using the MCA approach to study key variables of a simple metabolic system, in the context of an upper level biochemistry course. © 2018 International Union of Biochemistry and Molecular Biology, 46(5):502-515, 2018.


Assuntos
Bioquímica/educação , Eritrócitos/metabolismo , Glicólise , Colorimetria , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Eritrócitos/efeitos dos fármacos , Gliceraldeído-3-Fosfato Desidrogenases/antagonistas & inibidores , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Iodoacetamida/química , Iodoacetamida/farmacologia , Ácido Iodoacético/química , Ácido Iodoacético/farmacologia , Estudantes
5.
Salud pública Méx ; 57(1): 38-49, ene.-feb. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-736460

RESUMO

Objetivo. Comparar la salud, uso de servicios sanitarios y necesidad insatisfecha de atención médica (NIAM) entre inmigrantes y nativos del sureste español. Material y métodos. Estudio transversal de dos muestras representativas de población: inmigrante (n=1150) y nativa (n=1303; Encuesta Nacional de Salud). Se creó una única base de datos con ponderación específica para cada muestra y se estimaron razones de prevalencia (RP) mediante regresión multivariante. Resultados. Marroquíes, ecuatorianos y europeos del este (EE) declararon peor salud que los nativos (RPs [IC95%]: 2.45 [1.91-3.15]; 1.51 [1.28-1.79] y 1.44 [1.08-1.93], respectivamente). Los inmigrantes hicieron mayor uso de las urgencias (excepto EE) y consumieron menos fármacos. Los marroquíes mostraron la mayor diferencia en la frecuencia de NIAM (RP [IC95%]: 12.20 [5.25-28.37]), principalmente por razones laborales (46%). Conclusiones. La salud y el uso de servicios sanitarios difirieron significativamente entre inmigrantes y nativos. Destaca la NIAM alta en marroquíes por causa laboral.


Objective. To compare the self-perceived health, use of health services and unmet need for health care (UNHC) among immigrants and native populations of Southeast Spain. Materials and methods. Cross-sectional study of two representative samples of 1150 immigrants, and 1303 native participants from the National Health Survey. A single database was created with specific weights for each sample, and prevalence ratios (PR) were estimated by multivariate regression. Results. Moroccans, Ecuadorians and Eastern Europeans (EE) reported poorer health than the native population (PRs [CI95%]: 2.45 [1.91-3.15]; 1.51 [1.28-1.79] and 1.44 [1.08-1.93], respectively). Immigrants made greater use of emergencies that natives (except for EE) and had lower use of medication. Moroccan showed the greatest difference in the frequency of UNHC (PR [CI95%]:12.20 [5.25 - 28.37]), mainly because of working limitations (46%). Conclusions. The health status and use of health services among immigrants differ significantly from those of natives. Results highlight the higher frequency of UNHC among immigrants, especially high in Moroccans.


Assuntos
Animais , Humanos , Cisteína Endopeptidases/isolamento & purificação , Taenia solium/enzimologia , Cromatografia em Gel , Cromatografia por Troca Iônica , Colágeno/metabolismo , Cisteína Endopeptidases/química , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Imunoglobulina G/metabolismo , Ácido Iodoacético/farmacologia , Leucina/análogos & derivados , Leucina/farmacologia , Soroalbumina Bovina/metabolismo
6.
Glia ; 60(4): 674-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22290492

RESUMO

Neuronal activity is accompanied by a rapid increase in interstitial lactate, which is hypothesized to serve as a fuel for neurons and a signal for local vasodilation. Using FRET microscopy, we report here that the rate of glycolysis in cultured mice astrocytes can be acutely modulated by physiological changes in extracellular lactate. Glycolytic inhibition by lactate was not accompanied by detectable variations in intracellular pH or intracellular ATP and was not dependent of mitochondrial function. Pyruvate was also inhibitory, suggesting that the effect of lactate is not mediated by the NADH/NAD(+) ratio. We propose that lactate serves as a fast negative feedback signal limiting its own production by astrocytes and therefore the amplitude of the lactate surge. The inhibition of glucose usage by lactate was much stronger in resting astrocytes than in K(+)-stimulated astrocytes, which suggests that lactate may also help diverting glucose from resting to active zones.


Assuntos
Astrócitos/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Ácido Láctico/farmacologia , Trifosfato de Adenosina/metabolismo , Análise de Variância , Animais , Animais Recém-Nascidos , Astrócitos/citologia , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Células Cultivadas , Córtex Cerebral/citologia , Citocalasina B/farmacologia , Citosol/efeitos dos fármacos , Citosol/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Concentração de Íons de Hidrogênio , Ácido Iodoacético/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Potássio/farmacologia , Ionóforos de Próton/farmacologia , Rotenona/farmacologia
7.
Toxicol Sci ; 117(1): 133-43, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20573786

RESUMO

Ebselen (Ebs) and diphenyl diselenide [(PhSe)(2)] readily oxidize thiol groups. Here we studied mitochondrial swelling changes in mitochondrial potential (Deltapsim), NAD(P)H oxidation, reactive oxygen species production, protein aggregate formation, and oxygen consumption as ending points of their in vitro toxicity. Specifically, we tested the hypothesis that organochalchogens toxicity could be associated with mitochondrial dysfunction via oxidation of vicinal thiol groups that are known to be involved in the regulation of mitochondrial permeability (Petronilli et al. J. Biol. Chem., 269; 16638; 1994). Furthermore, we investigated the possible mechanism(s) by which these organochalchogens could disrupt liver mitochondrial function. Ebs and (PhSe)(2) caused mitochondrial depolarization and swelling in a concentration-dependent manner. Furthermore, both organochalchogens caused rapid oxidation of the mitochondrial pyridine nucleotides (NAD(P)H) pool, likely reflecting the consequence and not the cause of increased mitochondrial permeability (Costantini, P., Chernyak, B. V., Petronilli, V., and Bernardi, P. (1996). Modulation of the mitochondrial permeability transition pore (PTP) by pyridine nucleotides and dithiol oxidation at two separate sites. J. Biol. Chem. 271, 6746-6751). The organochalchogens-induced mitochondrial dysfunction was prevented by the reducing agent dithiothreitol (DTT). Ebs- and (PhSe)(2)-induced mitochondrial depolarization and swelling were unchanged by ruthenium red (4microM), butylated hydroxytoluene (2.5microM), or cyclosporine A (1microM). N-ethylmaleimide enhanced the organochalchogens-induced mitochondrial depolarization, without affecting the magnitude of the swelling response. In contrast, iodoacetic acid did not modify the effects of Ebs or (PhSe)(2) on the mitochondria. Additionally, Ebs and (PhSe)(2) decreased the basal 2' 7' dichlorofluorescin diacetate (H(2)-DCFDA) oxidation and oxygen consumption rate in state 3 and increased it during the state 4 of oxidative phosphorylation and induced the formation of protein aggregates, which were prevented by DTT. However, DTT failed to reverse the formation of protein aggregates, when it was added after a preincubation of liver mitochondria with Ebs or (PhSe)(2). Similarly, DTT did not reverse the Ebs- or (PhSe)(2)-induced Deltapsim collapse or swelling, when it was added after a preincubation period of mitochondria with chalcogenides. These results show that Ebs and (PhSe)(2) can effectively induce mitochondrial dysfunction and suggest that effects of these compounds are associated with mitochondrial thiol groups oxidation. The inability of cyclosporine A to reverse the Ebs- and (PhSe)(2)-induced mitochondrial effects suggests that the redox-regulated mitochondrial permeability transition (MPT) pore was mechanistically regulated in a manner that is distinct from the classical MPT pore.


Assuntos
Calcogênios/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Compostos de Sulfidrila/metabolismo , Animais , Hidroxitolueno Butilado/farmacologia , Ciclosporinas/farmacologia , Etilmaleimida/farmacologia , Ácido Iodoacético/farmacologia , Masculino , Mitocôndrias Hepáticas/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , NADP/metabolismo , Oxirredução , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-16298170

RESUMO

Despite the fact that anoxic goldfish hepatocytes can maintain the transmembrane gradients of Na(+), H(+) and Ca(2+), cyanide (CN) intoxication leads to a rapid breakdown of K(+) homeostasis. In this study, [(86)Rb(+)] K(+) fluxes across the plasma membrane of goldfish hepatocytes were studied in order to identify the possible causes of this imbalance. Four minutes of cyanide incubation induced an acute and stable 61% decrease of K(+) influx (mostly driven by Na,K-ATPase activity), whereas K(+) efflux increased by 24.3%, this imbalance yielding a net K(+) efflux of 0.279+/-0.024 nmol 10(-6) cells(-1) min(-1). This uncoupling was not observed when glycolytic ATP production was inhibited with iodoacetic acid. Although the CN-induced decrease of K(+) influx was fully reversible upon washout of the inhibitor, it could not be prevented by any of the following treatments: (1) addition of 2% bovine serum albumin, which binds extracellular fatty acids known to activate specific K(+) channels; (2) addition of ascorbate, which acts as a radical scavenger; (3) inclusion of 5 mM glucose as an extracellular carbon source; and (4) removal of medium oxygen (obtained by nitrogen bubbling). Regarding the elevation of K(+) efflux in the presence of CN, neither ATP-dependent K(+) channels nor the KCl cotransporter appeared to be activated, whereas BaCl(2), an inhibitor of voltage-gated K(+) channels, decreased K(+) efflux of CN-intoxicated cells to control levels. In summary, these results indicate that, in goldfish hepatocytes, the CN-induced K(+) imbalance results from acute Na,K-ATPase inhibition together with the activation of voltage-dependent K(+) channels, the latter probably resulting from transient membrane depolarization.


Assuntos
Membrana Celular/efeitos dos fármacos , Cianetos/toxicidade , Hipóxia/metabolismo , Potássio/metabolismo , Animais , Compostos de Bário/farmacologia , Membrana Celular/metabolismo , Células Cultivadas , Cloretos/farmacologia , Inibidores Enzimáticos/farmacologia , Gliceraldeído 3-Fosfato Desidrogenase (NADP+)/antagonistas & inibidores , Carpa Dourada , Hepatócitos , Homeostase/efeitos dos fármacos , Hipóxia/induzido quimicamente , Ácido Iodoacético/farmacologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/antagonistas & inibidores
9.
Biochem Genet ; 42(3-4): 69-84, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15168721

RESUMO

Polyacrylamide gel electrophoresis was used to analyze esterase patterns during development of Aedes aegypti from the cities of Marília and São José do Rio Preto (SJRP), Brazil. The zymograms showed a total of 23 esterase bands, 22 of which were in the specimens from Marília and 19 in those from SJRP. These esterase bands were considered to be the product of 23 alleles distributed tentatively in eight genetic loci. Most of the alleles were developmentally regulated. The larval stage expressed the greatest number of them (19 alleles, from the eight loci, in Marília; and 17 alleles, from seven loci, in SJRP). The pupal stage expressed 10 alleles from seven loci, in both populations, and the adult stage expressed 8 alleles from five and six loci in SJRP and Marília, respectively. Some alleles that were active in every stage were developmentally controlled at the level of expression (amount of product). A single allele was constitutively and highly expressed, in larvae, pupae, and adults, in both populations. Differences in esterase synthesis among stages are probably due to regulatory mechanisms acting in agreement with the requirements of a variable number of processes in which esterases are involved. The larval stage is the most active in developmental processes and shows very intense intake of food and very high mobility. These features may demand increased esterase production at that stage. Comparison of the two populations examined showed (besides the existence of alleles that they do not share) that they exhibit differences in the control of expression of other alleles. Such findings may reflect genetic differences between founders in each population, but the possibility of involvement of the intensive use of insecticides in SJRP is also discussed.


Assuntos
Aedes/enzimologia , Aedes/crescimento & desenvolvimento , Esterases/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Variação Genética , Alelos , Animais , Inibidores da Colinesterase/farmacologia , Eletroforese em Gel de Poliacrilamida , Esterases/efeitos dos fármacos , Esterases/genética , Feminino , Genética Populacional , Ácido Iodoacético/farmacologia , Estágios do Ciclo de Vida , Malation/farmacologia , Masculino , Mercaptoetanol/farmacologia , Fluoreto de Fenilmetilsulfonil/farmacologia , Fisostigmina/farmacologia , Fluoreto de Sódio/farmacologia , Especificidade por Substrato
10.
J Exp Biol ; 206(Pt 3): 513-22, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12502772

RESUMO

The relationship between cell volume and K(+) transmembrane fluxes of goldfish (Carassius auratus) hepatocytes exposed to anisotonic conditions or energetic limitation was studied and compared with the response of hepatocytes from trout (Oncorhynchus mykiss) and rat (Rattus rattus). Cell volume was studied by video- and fluorescence microscopy, while K(+) fluxes were assessed by measuring unidirectional (86)Rb(+) fluxes. In trout and rat hepatocytes, hyposmotic (180 mosmoll(-1)) exposure at pH 7.45 caused cell swelling followed by a regulatory volume decrease (RVD), a response reported to be mediated by net efflux of KCl and osmotically obliged water. By contrast, goldfish hepatocytes swelled but showed no RVD under these conditions. Although in goldfish hepatocytes a net ((86)Rb(+))K(+) efflux could be activated by N-ethylmaleimide, this flux was not, or only partially, activated by hyposmotic swelling (120-180 mosmoll(-1)). Blockage of glycolysis by iodoacetic acid (IAA) did not alter cell volume in goldfish hepatocytes, whereas in the presence of cyanide (CN(-)), an inhibitor of oxidative phosphorylation, or CN(-) plus IAA (CN(-)+IAA), cell volume decreased by 3-7%. Although in goldfish hepatocytes, energetic limitation had no effect on ((86)Rb(+))K(+) efflux, ((86)Rb(+))K(+) influx decreased by 57-66% in the presence of CN(-) and CN(-)+IAA but was not significantly altered by IAA alone. Intracellular K(+) loss after 20 min of exposure to CN(-) and CN(-)+IAA amounted to only 3% of the total intracellular K(+). Collectively, these observations suggest that goldfish hepatocytes, unlike hepatocytes of anoxia-intolerant species, avoid a decoupling of transmembrane K(+) fluxes in response to an osmotic challenge. This may underlie both the inability of swollen cells to undergo RVD but also the capability of anoxic cells to maintain intracellular K(+) concentrations that are almost unaltered, thereby prolonging cell survival.


Assuntos
Carpa Dourada/fisiologia , Hepatócitos/metabolismo , Potássio/metabolismo , Truta/fisiologia , Anaerobiose , Animais , Transporte Biológico/fisiologia , Tamanho Celular/efeitos dos fármacos , Tamanho Celular/fisiologia , Cianetos/farmacologia , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Soluções Hipertônicas/farmacologia , Soluções Hipotônicas/farmacologia , Ácido Iodoacético/farmacologia , Masculino , Microscopia de Fluorescência , Cloreto de Potássio/farmacologia , Ratos , Ratos Wistar , Radioisótopos de Rubídio , Sódio/metabolismo , Água/fisiologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-11133175

RESUMO

Involvement of arachidonic acid cyclooxygenase (COX) and lipoxygenase (LOX) metabolites in platelet aggregation and coagulation induced by two varieties of cancer cells of murine transplantable tumors was studied. A lung alveolar carcinoma (LAC) and a fibrosarcoma (FS), induced platelet aggregation and plasma coagulation (P<0.05). Pretreatment of both tumor lines with a COX inhibitor did not block the tumor cell induced platelet aggregation (TCIPA). COX [12(S)-HTT] and LOX [12(S)-HETE], metabolites of washed platelets (WP), alone or co-incubated with LAC or FS cells, were analyzed. We observed higher 12(S)-HETE release with respect to 12(S)HHT when WP were co-incubated with LAC cells. With both neoplastic cell (NC) lines prothrombin time (PT) was shortened. Pretreatment of NC with iodoacetic acid, soybean trypsin inhibitor or Factor X-deficient plasma increased the PT. These results indicate that AA metabolites play a role on the procoagulation and platelet aggregation induced by mesenchymal and epithelial murine cancers.


Assuntos
Adenocarcinoma Bronquioloalveolar/patologia , Coagulação Sanguínea/efeitos dos fármacos , Cisteína Endopeptidases/metabolismo , Eicosanoides/fisiologia , Fibrossarcoma/patologia , Lipoxigenase/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Neoplasias , Ativação Plaquetária/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/metabolismo , Adenocarcinoma Bronquioloalveolar/metabolismo , Animais , Ácidos Araquidônicos/metabolismo , Técnicas de Cocultura , Cisteína Endopeptidases/química , Eicosanoides/biossíntese , Eicosanoides/classificação , Fator X/fisiologia , Fibrossarcoma/metabolismo , Ácido Iodoacético/farmacologia , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Trombofilia/etiologia , Trombofilia/fisiopatologia , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
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