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1.
J Ethnopharmacol ; 120(1): 7-12, 2008 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-18703126

RESUMO

Acanthus ilicifolius Linn, is a perennial herb (Acanthaceae) widely found in the Sundarban mangroves and is popularly used for its wound healing effects. In the present study an attempt was made to evaluate the anti-inflammatory activity of the Acanthus ilicifolius leaves. The methanolic fraction of Acanthus ilicifolius leaf extract produced significant inhibition of rat paw oedema, when administered both prior to and after carrageenan administration, in a manner similar to BW755C a synthetic cyclooxygenase (COX) and lipoxygenase (LOX) inhibitor. The extract decreased protein exudation and leukocyte migration in the peritoneal fluid, thereby indicating its effectiveness towards inhibiting peritoneal inflammation. It also produced significant inhibition of COX (1 and 2) and 5-LOX activity. Preincubation of the extract inhibited the production of proinflammatory cytokines (TNFalpha and IL-6) in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). The methanolic fraction of the extract was also found to possess significant free radical (DPPH, ABTS, superoxide and hydroxyl radical) scavenging activity. The extract on intraperitoneal administration augmented the endogenous antioxidant status, as evident from the significant increase of ferric reducing ability of plasma (FRAP) and total peroxyl radical trapping activity of plasma (TRAP).


Assuntos
Acanthaceae/química , Anti-Inflamatórios/farmacologia , Edema/tratamento farmacológico , Extratos Vegetais/farmacologia , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Carragenina , Movimento Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/isolamento & purificação , Inibidores de Ciclo-Oxigenase/farmacologia , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Índia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Inibidores de Lipoxigenase/isolamento & purificação , Inibidores de Lipoxigenase/farmacologia , Masculino , Medicina Tradicional , Camundongos , Folhas de Planta , Ratos
2.
Am J Physiol Heart Circ Physiol ; 295(1): H89-96, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18456739

RESUMO

Arachidonic acid (AA) metabolites from the 15-lipoxygenase-1 (15-LO-1) pathway, trihydroxyeicosatrienoic acids (THETAs) and hydroxy-epoxyeicosatrienoic acids (HEETAs), are endothelium-derived hyperpolarizing factors (EDHFs) and relax rabbit arteries. Rabbit vascular 15-LO-1 expression, THETA and HEETA synthesis, and nitric oxide and prostaglandin-independent relaxations to acetylcholine (ACh) and AA decreased with age (neonates to 16-wk-old). We characterized age-dependent ACh-hypotensive responses in vivo in 1-, 4-, 8-, and 16-wk-old rabbits and the contribution of THETAs and HEETAs to these responses. In anesthetized rabbits, blood pressure responses to ACh (4-4,000 ng/kg) were determined in the presence of vehicle or various inhibitors. ACh responses decreased with age (P > 0.001). In the absence or presence of N(omega)-nitro-l-arginine methyl ester (l-NAME) and indomethacin (Indo), maximum responses in 1 (-54.7 +/- 7.4 and -37.9 +/- 3.9%)- and 4 (-48.8 +/- 2.4 and -35.5 +/- 7.8%)-wk-old rabbits were higher than 8 (-30.0 +/- 2.8 and -26.6 +/- 4.4%)- and 16 (-36.7 +/- 3.5 and -27.3 +/- 10%)-wk-old rabbits. A lipoxygenase inhibitor, BW755C, reduced THETA and HEETA synthesis in mesenteric arteries. In the presence of Indo and N(omega)-nitro-l-arginine, ACh relaxations were reduced by BW755C to a greater extent in the mesenteric arteries from the younger rabbits. In 4-wk-old rabbits treated with l-NAME and Indo, the maximum ACh hypotension was reduced by the potassium channel inhibitors apamin and charybdotoxin to -6.9 +/- 0.9%, by apamin alone to -19.5 +/- 1.4%, and by BW755C to -18.8 +/- 3.5%. The present study indicates that the age-related decrease in ACh-induced hypotension is mediated by the decreased synthesis of the 15-LO-1 metabolites THETAs and HEETAs.


Assuntos
Acetilcolina/farmacologia , Araquidonato 15-Lipoxigenase/metabolismo , Hipotensão/metabolismo , Artérias Mesentéricas/metabolismo , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Fatores Etários , Envelhecimento , Animais , Apamina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Charibdotoxina/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Relação Dose-Resposta a Droga , Eicosanoides/metabolismo , Hipotensão/fisiopatologia , Técnicas In Vitro , Indometacina/farmacologia , Inibidores de Lipoxigenase/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/enzimologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Coelhos
3.
Phytother Res ; 22(6): 814-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18446842

RESUMO

Infusions of Indian black tea (BTI), when administered orally, produced significant inhibition of rat paw oedema, induced with carrageenin (pre and post treatment) and arachidonic acid. BTI was also found to inhibit peritoneal capillary permeability and caused a marked reduction of lipopolysaccharide induced PGE(2) generation. In these models, the observed antioedema effect was similar to that of BW755C (a dual inhibitor of cyclooxygenase and 5-lipoxygenase enzymes). BTI was found to scavenge superoxide and hydroxyl radicals, and also protected rat erythrocytes from the damaging effects of hydrogen peroxide. In chronic studies, BTI inhibited granuloma formation along with the reduction of both lipid peroxidation and hydroxyproline content (in the granuloma tissue). Significant antiarthritic activity was observed with regular administration of BTI in the Freund's adjuvant induced model of arthritis. Chronic treatment with BTI (in arthritic rats) resulted in a decrease of paw diameter and tissue lipid peroxidation, along with a restoration of GSH, catalase and superoxide dismutase levels.


Assuntos
Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Folhas de Planta/química , Chá/química , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Ácido Acético , Doença Aguda , Animais , Ácido Araquidônico , Artrite Experimental/tratamento farmacológico , Artrite Experimental/imunologia , Doença Crônica , Edema/induzido quimicamente , Edema/tratamento farmacológico , Inflamação/induzido quimicamente , Lipopolissacarídeos/farmacologia , Masculino , Extratos Vegetais/química , Ratos
4.
Indian J Exp Biol ; 43(6): 493-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15991572

RESUMO

An attempt has been made in this communication to develop antiserum in rabbit against Scatophagus. argus sting extract. Antiserum did not neutralized the sting extract induced proinflammatory and haemorrhagic activity but successfully neutralized lethality upto 2LD50. Cyproheptadine, indomethacin and BW 755C pretreatment significantly reduced sting extract induced proinflammatory activity. The haemorrhagic activity of sting extract was significantly inhibited by temperature, UV-exposure, EDTA, cyproheptadine, indomethacin and BW 755C pretreatment. The results conclude that the local effects of S.argus venom is likely to be mediated through release of mediators and may be encountered by pharmacological antagonists better than the antiserum.


Assuntos
Venenos de Peixe/química , Venenos de Peixe/farmacologia , Soros Imunes/química , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Ciproeptadina/química , Edema/induzido quimicamente , Edema/patologia , Ácido Edético/química , Ácido Edético/farmacologia , Venenos de Peixe/imunologia , Hemaglutinação , Hemorragia/induzido quimicamente , Indometacina/farmacologia , Inflamação , Masculino , Camundongos , Perciformes , Coelhos , Ratos , Temperatura , Fatores de Tempo , Raios Ultravioleta
5.
Indian J Exp Biol ; 42(5): 452-60, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15233468

RESUMO

A haemorrhagic protein toxin (SA-HT) was isolated and purified from the spine extract of the Indian venomous butterfish, S. argus Linn, by two step ion exchange chromatography. The toxin was homogeneous in native and SDS-PAGE gel. SDS-molecular weight of the toxin was found to be 18.1 +/- 0.09 kDa. SA-HT produced severe haemorrhage on stomach wall but devoid of cutaneous haemorrhage. UV, EDTA, trypsin, protease, cyproheptadine, indomethacin, acetylsalicylic acid and BW755C treatment significantly antagonized the haemorrhagic activity of SA-HT. The toxin produced dose and time dependent oedema on mice hind paw, which was significantly encountered by cyproheptadine, indomethacin and BW755C. SA-HT increased capillary permeability on guinea pig dorsal flank. On isolated guineapig ileum, rat fundus and uterus, SA-HT produced slow contraction which was completely antagonised by prostaglandin blocker SC19220. On isolated rat duodenum, SA-HT produced slow relaxation. SA-HT significantly increased plasma plasmin, serum MDA level and decreased serum SOD level indicating the possible involvement of cyclooxygenase and lipooxygenase pathway.


Assuntos
Proteínas de Peixes/química , Proteínas de Peixes/isolamento & purificação , Venenos de Peixe/química , Venenos de Peixe/isolamento & purificação , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Capilares , Cromatografia por Troca Iônica , Ciproeptadina/farmacologia , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Ácido Edético/farmacologia , Eletroforese em Gel de Poliacrilamida , Feminino , Fármacos Gastrointestinais/farmacologia , Cobaias , Indometacina/farmacologia , Lipoxigenase/metabolismo , Camundongos , Músculo Liso/efeitos dos fármacos , Perciformes , Permeabilidade , Ratos , Coluna Vertebral/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Tempo , Tripsina/farmacologia , Raios Ultravioleta , Útero/efeitos dos fármacos
6.
Toxicon ; 40(12): 1709-17, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12457883

RESUMO

Staphylococcus aureus secretes enterotoxins which are superantigens and the major cause of food poisoning in man. Staphylococcal enterotoxins types A and B can induce neutrophil migration into the peritoneal cavity of mice through sensory C-fiber neuropeptides, lipoxygenase or cyclooxygenase metabolites, nitric oxide, histamine, platelet-activating factor and resident macrophages. In this work, we examined the influence of macrophage-derived products on neutrophil migration during peritonitis induced by staphylococcal enterotoxin type B (SEB) in mice. Macrophages stimulated with SEB released a thermolabile neutrophil chemotactic protein with a molecular weight of 1,000-3,000 (by ultrafiltration). This release was inhibited 30% by dexamethasone (an inhibitor of cytokine synthesis and phospholipase A(2) activity), but not by indomethacin (a cyclooxygenase inhibitor) or BW755C (a dual cyclo- and lipoxygenase inhibitor). Dexamethasone also inhibited (100%) the neutrophil migration induced by the chemotactic protein. Similar inhibition occurred in mice pretreated with BWA4C (lipoxygenase inhibitor; 90%), BW755C (99%), BN52021 (platelet-activating factor-acether receptor antagonist; 93%), cimetidine (histamine H(2) receptor antagonist; 76%), capsaicin (a depletor of sensory C-fiber neuropeptides; 82%) and the neurokinin-1 receptor antagonist SR140333 (71%), but not by indomethacin or the neurokinin(2) receptor antagonist SR48968. These results confirm that macrophages are involved in the neutrophil recruitment induced by SEB, and that the chemotactic protein apparently induces neutrophil migration by a mechanism mediated by platelet-activating factor, histamine H(2) receptors, lipoxygenase products and substance P.


Assuntos
Benzenoacetamidas , Quimiotaxia de Leucócito/efeitos dos fármacos , Diterpenos , Enterotoxinas/farmacologia , Interleucina-8/fisiologia , Infiltração de Neutrófilos/efeitos dos fármacos , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Capsaicina/farmacologia , Quimiotaxia de Leucócito/fisiologia , Cimetidina/farmacologia , Dexametasona/farmacologia , Inibidores Enzimáticos/farmacologia , Ginkgolídeos , Ácidos Hidroxâmicos/farmacologia , Indometacina/farmacologia , Lactonas/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Infiltração de Neutrófilos/fisiologia , Piperidinas/farmacologia , Quinuclidinas/farmacologia , Ratos , Ratos Wistar
7.
Phytother Res ; 16(4): 331-5, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12112288

RESUMO

Studies were carried out to evaluate the influence of the methanol fraction of Pluchea indica Less root extract (PIRE), the dual inhibitors (BW 755C and phenidone) and vitamin on both in vivo and in vitro free radical-scavenging activities, CCl(4)-induced lipid peroxidation and the metabolism of arachidonic acid by lipoxygenase. PIRE produced significant antiinflammatory activity against glucose oxidase-induced paw oedema (in vivo), inhibited hydroxyl radical and superoxide generation, lysis of erythrocytes induced by hydrogen peroxide, CCl(4)-induced lipid peroxidation and also dioxygenase activity of lipoxygenase (both in the presence and absence of hydrogen peroxide). Significantly higher free radical-scavenging activity was observed with BW 755C and phenidone compared with PIRE. However, both BW 755C and phenidone stimulated hydroxyl radical generation compared with the observed inhibitory effects of PIRE and vitamin E.


Assuntos
Antioxidantes/farmacologia , Asteraceae/química , Peroxidação de Lipídeos/efeitos dos fármacos , Metanol/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/química , Antioxidantes/uso terapêutico , Ácido Araquidônico/metabolismo , Tetracloreto de Carbono/farmacologia , Edema/tratamento farmacológico , Edema/patologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/uso terapêutico , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila/metabolismo , Inflamação/tratamento farmacológico , Inflamação/patologia , Lipoxigenase/metabolismo , Camundongos , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Pirazóis/farmacologia , Superóxidos/metabolismo , Vitamina E/farmacologia
8.
Inflamm Res ; 50(4): 206-12, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11392608

RESUMO

OBJECTIVE AND DESIGN: To examine the role of macrophages in the neutrophil migration induced by staphylococcal enterotoxin type A (SEA) in mice. MATERIALS AND METHODS: Peritoneal macrophages were harvested from male Swiss mice pre-treated with thioglycollate. After adhering to plastic tissue culture dishes, the cells were washed and incubated with RPMI or SEA (0.62-2.5 microg/ml) and washed again prior to further incubation with RPMI alone. The medium was then collected, sterilized and assayed for promigratory activity in the mouse peritoneal cavity. RESULTS: Mouse macrophage monolayers stimulated with SEA secreted a thermolabile neutrophil chemotactic component (MNCC-SEA) with a molecular mass >100 kDa (by ultrafiltration). This release was dose- and time-dependent and was inhibited by dexamethasone but not by indomethacin or BW755C. Dexamethasone, indomethacin, BWA4C, BW755C, BN52021, cimetidine and SR48968 had no effect on the neutrophil migration induced by MNCC-SEA while capsaicin and SR 140333 reduced this phenomenon. CONCLUSIONS: Macrophages play a key role in the neutrophil recruitment induced by SEA probably by releasing an MNCC-SEA that presumably induces neutrophil migration via a mechanism mediated by substance P.


Assuntos
Fatores Quimiotáticos/metabolismo , Enterotoxinas/farmacologia , Macrófagos Peritoneais/metabolismo , Neutrófilos/fisiologia , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Benzamidas/farmacologia , Cálcio/farmacologia , Capsaicina/farmacologia , Fatores Quimiotáticos/farmacologia , Quimiotaxia de Leucócito , Inibidores de Ciclo-Oxigenase/farmacologia , Dexametasona/farmacologia , Estabilidade de Medicamentos , Glucocorticoides/farmacologia , Glucose/farmacologia , Indometacina/farmacologia , Magnésio/farmacologia , Masculino , Camundongos , Peso Molecular , Piperidinas/farmacologia , Receptores da Neurocinina-2/antagonistas & inibidores , Tioglicolatos/farmacologia
9.
J Leukoc Biol ; 69(4): 659-65, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11310854

RESUMO

Phosphorylation of extracellular signal-regulated kinase (ERK) in response to arachidonic acid (AA) was rapid and transient, peaking at 1 min and disappearing after 3 min, and it was accompanied by an increase in ERK activity in rat neutrophils. We examined the upstream regulation of AA-stimulated ERK activation using one of the following signaling pathway inhibitors to pretreat rat cells: the ERK kinase inhibitor U0126 or PD98059, the G(i/o) inhibitor pertussis toxin (PTX), the tyrosine kinase inhibitor genistein, the phosphatidylinositol 3-kinase (PI3K) inhibitor wortmannin or LY294002, the Ca2+ chelator 1,2-bis(O-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid, or the phospholipase C (PLC) inhibitor U73122. All of these inhibitors attenuated AA-induced ERK activation. Activation of ERK was also effectively attenuated by the cyclooxygenase and lipoxygenase inhibitor BW755C and by the leukotriene biosynthesis inhibitor MK886, but the cyclooxygenase inhibitor indomethacin did not attenuate ERK activation. After exposing cells to three distinct protein kinase C (PKC) inhibitors, we found that Gö6976 significantly attenuated ERK phosphorylation but potentiated ERK activity. Neither Gö6983 nor GF109203X affected AA-induced responses. These data suggest that the lipoxygenase metabolite(s) produced mediates AA-stimulated ERK activation and that this effect is upstream regulated by PT-sensitive G protein, non-receptor tyrosine kinase, PI3K, and PLC/Ca2+ signaling pathways in rat neutrophils.


Assuntos
Ácido Araquidônico/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neutrófilos/efeitos dos fármacos , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Androstadienos/farmacologia , Animais , Ácidos Araquidônicos/farmacologia , Butadienos/farmacologia , Cálcio/fisiologia , Carbazóis/farmacologia , Quelantes/farmacologia , Cromonas/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Flavonoides/farmacologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/antagonistas & inibidores , Proteínas Heterotriméricas de Ligação ao GTP/antagonistas & inibidores , Indóis/farmacologia , Inibidores de Lipoxigenase/farmacologia , Maleimidas/farmacologia , Proteína Quinase 3 Ativada por Mitógeno , Morfolinas/farmacologia , Neutrófilos/metabolismo , Nitrilas/farmacologia , Toxina Pertussis , Fosfatidilinositol Diacilglicerol-Liase , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Pirrolidinonas/farmacologia , Ratos , Ratos Sprague-Dawley , Fosfolipases Tipo C/antagonistas & inibidores , Fatores de Virulência de Bordetella/farmacologia , Wortmanina
10.
Otolaryngol Head Neck Surg ; 123(1 Pt 1): 1-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10889472

RESUMO

Abnormal bone remodeling is associated with important otolaryngologic diseases. In such diseases, the mechanisms of osteoclastic control underlie the pathologic processes. It is known that strain applied to auditory bullae induces bone resorption-an effect mediated by prostaglandins and blocked by cyclo-oxygenase inhibitors. It is also known that cyclo-oxygenase inhibition shunts arachidonic acid into alternate metabolic pathways, mainly the lipoxygenase pathway with leukotriene production. The role of these metabolites in adaptive bone remodeling is unknown. Using the gerbilline bulla as a model, we infused BW755c (dual lipoxygenase/cyclo-oxygenase inhibitor) and L-663,536 (5-lipoxygenase inhibitor) into animals undergoing middle ear pressurization. After 7 days, the bulla bones were harvested, and osteoclasts were quantified histomorphometrically. The results showed that neither treatment altered pressure-induced resorption. However, BW755c significantly increased resorption in unpressurized bone when compared with control values. Because BW775c blocks both lipoxygenase and cyclo-oxygenase pathways, the results suggest an alternate pathway in middle ear bone resorption.


Assuntos
4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Distinções e Prêmios , Remodelação Óssea/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Orelha Média/efeitos dos fármacos , Indóis/farmacologia , Internato e Residência , Inibidores de Lipoxigenase/farmacologia , Otolaringologia/educação , Animais , Reabsorção Óssea/patologia , Gerbillinae , Masculino , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia
11.
Brain Res Mol Brain Res ; 76(2): 419-23, 2000 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-10762721

RESUMO

Accumulation of arachidonic acid (AA) in the brain during ischaemia may contribute to development of brain oedema. In this study we investigated the effect of selected drugs on AA-induced cytotoxic brain oedema in C6 glioma cells. Suspended C6 glioma cells were preincubated with drugs and AA (0.1 mM) was added. When no drug was administered cell volume increased immediately after the addition of AA with a maximum cell swelling of 13.1+/-1.9% at 15 min (mean +/- S.E. M.). Preincubation of cells with BW 755C, a dual inhibitor of cyclo- and lipoxygenases, showed no reduction in cell swelling from AA, whereas superoxide dismutase, amiloride and the protein kinase inhibitor H-9370 led to a significant attenuation of volume increase (p<0.05). The role of Na(+) ions during cell swelling from AA was evaluated after pretreatment of C6 glioma cells with ouabain. This resulted in a reversal of cell swelling (p<0.01). We conclude that there is potential involvement of free radicals, signal transduction systems and intracellular accumulation of Na(+) ions in glial cell swelling from AA.


Assuntos
Ácido Araquidônico/farmacologia , Edema Encefálico , Neuroglia/citologia , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Amilorida/farmacologia , Animais , Tamanho Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glioma , Modelos Neurológicos , Neuroglia/efeitos dos fármacos , Neuroglia/fisiologia , Ouabaína/farmacologia , Superóxido Dismutase/antagonistas & inibidores , Células Tumorais Cultivadas
12.
Immunology ; 96(1): 90-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10233682

RESUMO

Since arachidonic acid (AA) production by phospholipase A2 (PLA2) is essential for the Fcgamma receptor (FcgammaR)-mediated respiratory burst and phagocytosis of opsonized erythrocytes by monocytes and macrophages, we focused in this study on the role of AA and its metabolites in the FcgammaR-stimulated intracellular killing of Staphylococcus aureus by human monocytes. The results revealed that the PLA2 inhibitors, but not inhibitors of cyclo-oxygenase and lipoxygenase, markedly suppressed the FcgammaR-mediated killing process. The production of O-2 by monocytes upon FcgammaR cross-linking was inhibited by 4-bromophenacyl bromide in a dose-dependent fashion, indicating that inhibition of PLA2 activity impairs the oxygen-dependent bactericidal mechanisms of monocytes, which could be partially restored by addition of exogenous AA and docosahexaenoic acid, but not myristic acid. These polyunsaturated fatty acids, but not myristic acid, stimulated the intracellular killing of S. aureus by monocytes, although not as effectively as FcgammaR cross-linking. Furthermore, FcgammaR cross-linking stimulated the release of AA from monocytes. Studies with selective inhibitors revealed that the FcgammaR-mediated activation of PLA2 is dependent on Ca2+ and tyrosine kinase activity. Together these results indicate a key role for PLA2/AA, but not its major metabolites, in mediating the FcgammaR-stimulated intracellular killing of S. aureus by monocytes.


Assuntos
Ácido Araquidônico/metabolismo , Imunoglobulina G/metabolismo , Monócitos/fisiologia , Fagocitose/efeitos dos fármacos , Receptores de IgG/metabolismo , Staphylococcus aureus , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Acetofenonas/farmacologia , Ácido Araquidônico/farmacologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Inibidores de Ciclo-Oxigenase/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Genisteína/farmacologia , Humanos , Imunoglobulina G/farmacologia , Indometacina/farmacologia , Inibidores de Lipoxigenase/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Oxigênio/metabolismo , Fosfolipases A/antagonistas & inibidores , Fosfolipases A/metabolismo , Fosfolipases A2 , Proteína Quinase C/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Sulfonamidas/farmacologia
13.
Eur J Pharmacol ; 356(2-3): 231-7, 1998 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-9774254

RESUMO

Hypoxic pulmonary vasoconstriction is an essential mechanism that matches lung perfusion to ventilation, thus optimising pulmonary gas exchange. Despite its pathophysiological relevance, the mechanism of hypoxic pulmonary vasoconstriction still remains enigmatic. We investigated whether arachidonic acid metabolism is involved in the regulation of hypoxic pulmonary vasoconstriction in isolated, buffer-perfused rabbit lungs. Seven inhibitors were employed to determine the contribution of different vasoactive lipoxy- and cyclooxygenase mediators as well as cytochrome P450 products on the magnitude of hypoxic pulmonary vasoconstriction. Hypoxic pulmonary vasoconstriction was not affected by (i) the cyclooxygenase inhibitor acetylsalicylic acid, (ii) the thromboxane A2 receptor antagonist BM13.505, (iii) the 5'-lipoxygenase inhibitor MK886, and (iv) the lipoxygenase and cyclooxygenase inhibitor BW755c. The hypoxia-elicited pressor response was prominently inhibited by (i) nordihydroguaiaretic acid (50-150 microM), an inhibitor of lipoxygenase and cyclooxygenase and (ii) methoxsalen (100 microM) and 1-aminobenzotriazole (1-10 mM), two inhibitors of cytochrome P450-derived metabolites. However, no specificity for the regulation of hypoxic pulmonary vasoconstriction was found, as corresponding inhibitory potency of these agents was noted when vasoconstriction was achieved by the stable thromboxane analogue U46619 under conditions of normoxia. We conclude that there is no evidence for a specific involvement of different pathways of arachidonic acid metabolism in the mechanism of hypoxic pulmonary vasoconstriction in rabbits.


Assuntos
Ácido Araquidônico/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Hipóxia/fisiopatologia , Inibidores de Lipoxigenase/farmacologia , Pulmão/efeitos dos fármacos , Vasoconstrição/fisiologia , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Aspirina/farmacologia , Interações Medicamentosas , Feminino , Hipóxia/metabolismo , Indóis/farmacologia , Pulmão/metabolismo , Masculino , Masoprocol/farmacologia , Coelhos , Vasoconstrição/efeitos dos fármacos
14.
Br J Pharmacol ; 125(2): 271-6, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9786498

RESUMO

1. The release of neuronal [3H]acetylcholine (ACh) from isolated human bronchi after labelling with [3H]choline was measured to investigate the effects of prostanoids. 2. A first period of electrical field stimulation (S1) caused a [3H]ACh release of 320+/-70 and 200+/-40 Becquerel (Bq) g(-1) in epithelium-denuded and epithelium-containing bronchi respectively (P>0.05). Subsequent periods of electrical stimulation (Sn, n=2, 3, and 4) released less [3H]ACh, i.e. decreasing Sn/ S1 values were obtained (0.76+/-0.09, 0.68+/-0.07 and 0.40+/-0.04, respectively). 3. Cumulative concentrations (1-1000 nM) of EP-receptor agonists like prostaglandin E2, nocloprost, and sulprostone (EP1 and EP3 selective) inhibited evoked [3H]ACh release in a concentration dependent manner with IC50 values between 4- 14 nM and maximal inhibition of about 70%. 4. The inhibition of evoked [3H]ACh release by prostaglandin E2, nocloprost and sulprostone was not affected by the DP-, EP1- and EP2-receptor antagonist AH6809 at a concentration of 3 microM, i.e. a 3-30 times greater concentration than its affinity (pA2 values) at the respective receptors. 5. Circaprost (IP-receptor agonist; 1-100 nM), iloprost (IP- and EP1-receptor agonist; 10-1000 nM) and U-46619 (TP-receptor agonist; 100-1000 nM) did not significantly affect [3H]ACh release. 6. Blockade of cyclooxygenase by 3 microM indomethacin did not significantly modulate evoked [3H]ACh release in epithelium-containing and epithelium-denuded bronchi. Likewise, the combined cyclo- and lipoxygenase inhibitor BW-755C (20 microM) did not affect evoked [3H]ACh release. 7. In conclusion, applied prostanoids appear to inhibit [3H]ACh release in epithelium-denuded human bronchi under the present in vitro conditions, most likely via prejunctional prostanoid receptors of the EP3 subtype.


Assuntos
Acetilcolina/metabolismo , Brônquios/efeitos dos fármacos , Prostaglandinas/farmacologia , Receptores de Prostaglandina E/metabolismo , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Brônquios/metabolismo , Humanos , Técnicas In Vitro , Indometacina/farmacologia , Receptores de Prostaglandina E/efeitos dos fármacos , Trítio
15.
Arch Physiol Biochem ; 105(4): 358-64, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9711356

RESUMO

The aim of the study was to estimate an eventual contribution of leukotrienes in respiratory mechanic changes observed in guinea-pig during bronchial anaphylaxis. Twenty-eight guinea-pigs, actively sensitized to ovalbumin, were anesthetized and curarized before being challenged, during controlled ventilation, with antigen administered as an aerosol. Antigen challenge was performed before and after pretreatment with nebulized FPL55712 and BW755C, respectively used as an antagonist of leukotrienes and as a cyclo-oxygenase/lipoxygenase inhibitor. The experiments were carried out during continuous recording of tracheal pressure (Ptr), airflow (V) and tidal volume (VT) signals variations evidencing respiratory asynchronism (AS) and allowing measurements of the changes in airway resistance (AR) and dynamic compliance (Cdyn) during all the challenge. Administration of nebulized ovalbumin was stopped at the onset of AS appearance chosen as the threshold of the antigen-induced bronchoconstriction. The results showed that separate or combined pretreatment with FPL55712 and BW755C did not significantly modify the threshold of the ovalbumin-induced bronchoconstriction in guinea-pigs. Nevertheless pretreatment with nebulized FPL55712 reduced significantly the intensity and the duration of the response of these animals to inhaled leukotriene D4 (LTD4). Moreover the response of guinea-pigs to inhaled LTD4, characterized by a starting decrease in Cdyn, appeared quite different from the response to the antigen starting by an abrupt rise in RA induced by a sudden bronchoconstriction. From these results, we concluded that leukotrienes seem not to be the main mediator of the bronchial anaphylaxis in guinea-pigs.


Assuntos
4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Cromonas/farmacologia , Antagonistas de Leucotrienos/farmacologia , Inibidores de Lipoxigenase/farmacologia , Ovalbumina/imunologia , SRS-A/fisiologia , Administração por Inalação , Animais , Testes de Provocação Brônquica , Feminino , Cobaias , Imunização , Leucotrieno D4 , Masculino , SRS-A/antagonistas & inibidores
17.
Inflamm Res ; 46(9): 361-5, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9339392

RESUMO

OBJECTIVE AND DESIGN: The present paper examines the possible pharmacological mediators involved in mouse hind paw inflammation induced by staphylococcal enterotoxin type A (SEA). MATERIALS AND METHODS: The edema and the Evans blue exudation were measured in male Swiss mice (20-25 g) using methods described by Levy and Griswold, respectively. RESULTS: SEA (32 micrograms/paw) produced a biphasic, long-lasting, dose- and time-dependent edematogenic response. The acute phase edema was pronounced while the chronic edema was of a low intensity. Exudate was the principal component of the edema. The edematogenic effect of SEA appears to involve cyclooxygenase products and was dose-dependently reduced by pretreating the mice with dexamethasone, indomethacin, BW755C, WEB2086, capsaicin, diphenhydramine or cimetidine. CONCLUSIONS: These results demonstrate that SEA-induced mouse hind paw inflammation is a useful model for studying SEA-mediated enterotoxemia and may be sufficiently sensitive to differentiate between the effects of SEA and those of SE type B (SEB).


Assuntos
Enterotoxinas , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/uso terapêutico , Animais , Azepinas/uso terapêutico , Capsaicina/uso terapêutico , Cimetidina/uso terapêutico , Dexametasona/uso terapêutico , Difenidramina/uso terapêutico , Edema/induzido quimicamente , Edema/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Membro Posterior , Antagonistas dos Receptores Histamínicos/farmacologia , Indometacina/uso terapêutico , Masculino , Camundongos , Inibidores da Agregação Plaquetária/farmacologia , Triazóis/uso terapêutico
18.
Pharmacol Res ; 36(2): 103-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9344637

RESUMO

The effect of BW755C (a dual inhibitor of cyclo- and lipoxygenase enzymes) alone and in combination with iloprost (a PGI2 analogue) on myocardial reperfusion injury was investigated in anaesthetised open-chest dogs. The left anterior descending coronary artery was occluded for a period of 40 min followed by reperfusion for 3 h. Dogs were administered either saline, BW755C (10 mg kg-1 slow bolus) or BW755C plus iloprost (100 ng kg-1 min-1 for 75 min) just prior to reperfusion. The haemodynamic data showed significant reduction in MAP and both LV peak-positive and peak-negative dP/dt following reperfusion in the saline-treated group, along with a delayed recovery of LVEDP. These changes were accompanied by significant depletion of myocardial ATP and glycogen stores. Administration of BW755C prevented the haemodynamic changes and replenished the HEP stores. Although coadministration of iloprost with BW755C afforded early normalisation of LVEDP and LV peak positive dP/dt, but MAP and LV peak negative dP/dt remained significantly depressed. Therefore, it might be concluded from this study that supplementation of BW755C with iloprost may have deleterious haemodynamic effects on the reperfused myocardium, particularly in the doses used.


Assuntos
4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/uso terapêutico , Inibidores de Ciclo-Oxigenase/uso terapêutico , Coração/efeitos dos fármacos , Iloprosta/farmacologia , Inibidores de Lipoxigenase/uso terapêutico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Vasodilatadores/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Cães , Antagonismo de Drogas , Coração/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/fisiopatologia
19.
Lipids ; 31(12): 1265-8, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8972459

RESUMO

Lysophosphatidic acid (LPA, 1-acyl-sn-glycerol 3-phosphate), at a concentration of 1-40 microM, was found to induce the formation of [3H]inositol-labelled phosphatidylinositol-4-phosphate (PIP) without significantly altering the levels of either phosphatidylinositol (PI) or phosphatidylinositol bisphosphate (PIP2) in washed human platelets. Preincubation of platelets with the cyclooxygenase/lipoxygenase inhibitor, BW755C at 100 microM, did not alter the LPA-induced formation of PIP. Activation of platelets with the phorbol ester, phorbol 12-myristate 13-acetate (PMA), elicited a similar response (induction of PIP formation). The specific protein kinase C (PKC) inhibitor, GF109203X (10 microM), completely blocked the effect of PMA but not the LPA-induced generation of PIP. The present results indicate that LPA can induce PIP formation via PI-4-kinase activation, through processes which are independent of the eicosanoid/TxA2 pathway and are not PKC-dependent.


Assuntos
Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Lisofosfolipídeos/farmacologia , Fosfatos de Fosfatidilinositol/sangue , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Eicosanoides/sangue , Inibidores Enzimáticos/farmacologia , Humanos , Técnicas In Vitro , Inibidores de Lipoxigenase/farmacologia , Fosfatidilinositol 4,5-Difosfato/sangue , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/sangue , Acetato de Tetradecanoilforbol/farmacologia , Tromboxano A2/sangue
20.
Gastroenterology ; 111(4): 945-58, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8831589

RESUMO

BACKGROUND & AIMS: Although epidermal growth factor (EGF) inhibits gastric acid secretion, the effects it exerts on gastric chief cells are unknown. The aim of this study was to investigate whether EGF modulates pepsinogen release and intracellular Ca2+ concentrations ([Ca2+]i) and whether the effect involves mitogen-activated protein (MAP) kinase, eicosanoid generation, and nitric oxide. METHODS: Chief cells were obtained by sequential digestion with collagenase and Ca2+ chelation. [Ca2+]i was measured in cells loaded with Fura-2 and NO generation by the NO coproduct citrulline. RESULTS: In situ hybridization, immunohistochemistry, and immunoblotting showed that EGF receptor and MAP kinases were constitutively expressed in chief cells. EGF caused a concentration-dependent stimulation of pepsinogen secretion and MAP kinase activity and determined a 2.5-7.0-fold increase in [Ca2+]i, inositol 1,4,5-tryphosphate, prostaglandin E2, and leukotriene B4. Tyrosine kinase inhibitors and cyclooxygenase and lipoxygenase inhibitors reduced pepsinogen secretion and eicosanoid generation induced by EGF. EGF increased citrulline generation and guanosine 3',5'-cyclic monophosphate accumulation sixfold; the effect was blocked by NG monomethyl-L-arginine, which is an NO synthase inhibitor. CONCLUSIONS: EGF stimulates pepsinogen secretion by activating eicosanoid generation, tyrosine kinases, MAP kinases, Ca2+, NO, and guanosine 3',5'-cyclic monophosphate.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Pepsinogênios/metabolismo , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Cálcio/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , GMP Cíclico/metabolismo , Receptores ErbB/análise , Mucosa Gástrica/metabolismo , Cobaias , Inositol 1,4,5-Trifosfato/biossíntese , Masculino , Óxido Nítrico/biossíntese , Timidina/metabolismo
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