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1.
Sci Total Environ ; 912: 169060, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38061642

RESUMO

Historically, forest thinning in Japan was conducted to obtain high-quality timber from plantations. Today, in contrast, thinning is also motivated by forest water balance and climate change considerations. It is in this context that the present study examines the effects of thinning on the ecophysiological responses of remaining trees, which are inadequately understood, especially in relation to changes in the magnitude and duration of transpiration. Sap flux densities were measured in both outer and inner sapwood to obtain stand-scale transpiration for two years in the pre-thinning state and three years post-thinning. The effects of thinning on transpiration were quantitatively evaluated based on canopy conductance models. The larger increases in outer sap flux density were found in the first year after the treatment, while those in inner sap flux density were detected in the second and third years. The remaining trees required a few of years to adjust to improved light conditions of the lower crown, resulting in a delayed response of inner sap flux density. As a result of this lag, transpiration was reduced to 71 % of the pre-thinning condition in the first year, but transpiration recovered to the pre-thinning levels in the second and third years due to compensating contributions from inner sap flow. In terms of more accurately chronicling the thinning effect, the distribution of sap flux density with respect to its radial pattern, is necessary. Such measurements are key to more comprehensively examining the ecophysiological response of forest plantations to thinning and, ultimately, its effect on the forest water balance.


Assuntos
Cryptomeria , Cryptomeria/fisiologia , Transpiração Vegetal/fisiologia , Florestas , Árvores/fisiologia , Água
2.
BMJ Case Rep ; 12(1)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30635311

RESUMO

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterised by thromboembolic events including venous thromboembolism (VTE) in association with the presence of antiphospholipid antibodies. The standard treatment of VTE historically consists of anticoagulation therapy with warfarin, a vitamin K antagonist. Recently, direct oral anticoagulants, including rivaroxaban have become available for the treatment of VTE. However, the choice of anticoagulant, and the duration of anticoagulation in patients with APS has not been determined yet due to lack of evidence. Here, we report a case of recurrent venous thrombosis after discontinuation of rivaroxaban therapy and avoiding sedentary lifestyle in a patient with APS. We suggest that indefinite anticoagulation therapy might be needed even in low-risk APS cases.


Assuntos
Síndrome Antifosfolipídica/complicações , Rivaroxabana/uso terapêutico , Tromboembolia Venosa/etiologia , Trombose Venosa/etiologia , Assistência ao Convalescente , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/patologia , Inibidores do Fator Xa/uso terapêutico , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/etiologia , Recidiva , Rivaroxabana/administração & dosagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Tromboembolia Venosa/diagnóstico por imagem , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/tratamento farmacológico
3.
Exp Ther Med ; 14(4): 3233-3238, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28928804

RESUMO

Leukotriene receptor antagonists (LTRAs) are identified as a monotherapy for asthma and allergic rhinitis; however, their use in children for treatment of these diseases has not been examined. Accordingly, the present study investigated the efficacy of pranlukast dry syrup for children with both pollinosis and asthma. The subjects were children receiving treatment for asthma who were also diagnosed with cedar pollen allergy. Patients were divided into a group that received continuous treatment with pranlukast (group A; n=20) and a group that commenced add-on treatment for pollinosis following the onset of symptoms (group B; n=20). Patients in group B were randomly allocated to subgroup B1 (add-on treatment with pranlukast dry syrup) or subgroup B2 (add-on treatment with a second-generation antihistamine). In both groups, nasal and ocular symptoms were evaluated every day and recorded in a diary. Exacerbation of nasal obstruction was demonstrated in group B; however, not in group A. There was a significant difference in symptoms observed between the two groups during the late peak pollen period (P<0.05). The incidence of nasal obstruction (defined as a nasal obstruction score ≥3 or use of a nasal steroid spray) was significantly lower in group A compared with group B (P<0.05). The maximum scores for sneezing and nasal obstruction during the late peak of the pollen season were lowest in group A, followed by subgroup B1 and subgroup B2. The present study demonstrated that long-term administration of LTRA for the management of asthma may improve nasal symptoms of pollinosis during the pollen season in children with pollinosis and asthma.

4.
Allergol Int ; 61(3): 405-10, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22627847

RESUMO

BACKGROUND: Virus infection is an important risk factor for aggravation of childhood asthma. The objective of this study was to examine the effect of drugs on aggravation of asthma induced by a common cold. METHODS: Asthma control was examined in a survey of 1,014 Japanese pediatric patients with bronchial asthma. The occurrence of common cold, asthma control, and drugs used for asthma control were investigated using a modified Childhood Asthma Control Test (C-ACT) for patients aged <4 years old and 4 to 11 years old, and an Asthma Control Test (ACT) for patients aged 12 to 15 years old. RESULTS: The status of asthma control did not differ among the age groups. The prevalence of common cold and aggravation of asthma were significantly higher in patients aged <4 years old. Control of asthma following common cold-induced aggravation was significantly less effective in patients aged <4 years old compared to those aged ≥4 years old. In patients aged <4 years old with a common cold, asthma control was significantly more effective for those treated with leukotriene receptor antagonists (LTRAs) compared to treatment without LTRAs. Asthma control did not differ between patients who did or did not take inhaled corticosteroids or long-acting ß2 stimulants. CONCLUSIONS: These findings showed a high prevalence of common cold in younger patients with childhood asthma and indicated that common cold can induce aggravation of asthma. LTRAs are useful for long-term asthma control in very young patients who develop an asthma attack due to a common cold.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Asma/etiologia , Resfriado Comum/complicações , Antagonistas de Leucotrienos/uso terapêutico , Antiasmáticos/administração & dosagem , Asma/epidemiologia , Criança , Pré-Escolar , Resfriado Comum/epidemiologia , Progressão da Doença , Feminino , Humanos , Antagonistas de Leucotrienos/administração & dosagem , Masculino , Prevalência , Resultado do Tratamento
5.
Biol Pharm Bull ; 33(10): 1763-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20930390

RESUMO

Tulobuterol patches are long-acting bronchodilators for percutaneous absorption including the ß(2)-adrenoreceptor agonist tulobuterol, as a main ingredient, used for long-term management of pediatric asthma. Since patients who have pediatric asthma often also have atopic dermatitis in which the skin barrier is impaired, we compared the skin penetration profiles of the brand and generic patches using a skin barrier-impaired rat model. Skin penetration was significantly (p<0.001) higher in the generic patches compared with the brand patch, suggesting that it is important to understand the pharmaceutical properties of available products by giving careful consideration not only to the patient's asthma control but also to their skin condition before using tulobuterol patches.


Assuntos
Broncodilatadores/farmacocinética , Medicamentos Genéricos/farmacocinética , Absorção Cutânea , Pele/metabolismo , Terbutalina/análogos & derivados , Adesivo Transdérmico , Animais , Asma/tratamento farmacológico , Broncodilatadores/administração & dosagem , Modelos Animais de Doenças , Medicamentos Genéricos/administração & dosagem , Feminino , Patentes como Assunto , Ratos , Ratos Sprague-Dawley , Terbutalina/administração & dosagem , Terbutalina/farmacocinética
6.
Int Arch Allergy Immunol ; 152(3): 295-300, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20150748

RESUMO

BACKGROUND: Although neurogenic inflammation of the airways via activation of C-fibers is thought to be important in the pathogenesis of asthma, the mechanisms regulating C-fiber activity remain uncertain. OBJECTIVE: The influence of a cannabinoid receptor agonist, WIN 55,212-2, on C-fiber activation in guinea pig airways was investigated, as was the mechanism by which cannabinoids regulate antigen-induced airway inflammation. METHODS: The inhibitory effect of WIN 55,212-2 on antigen-induced plasma extravasation was assessed in guinea pig tracheal tissues by photometric measurement of extravasated Evans blue dye after extraction with formamide. RESULTS: Pretreatment with WIN 55,212-2 (0.001, 0.01 or 0.1 mg/kg) significantly and dose-dependently reduced tracheal plasma extravasation induced by inhaling a 5% ovalbumin solution for 2 min after pretreatment with a neutral endopeptidedase inhibitor (phosphoramidon at 2.5 mg/kg i.v.). A cannabinoid CB2 receptor antagonist (SR144528) blunted the inhibitory effect of WIN 55,212-2, while a cannabinoid CB1 antagonist (SR141716A) did not. Pretreatment with a neurokinin-1 receptor antagonist (FK888) significantly reduced ovalbumin-induced extravasation of Evans blue dye. Pretreatment with the combination of WIN 55,212-2 and FK888 reduced antigen-induced plasma extravasation more markedly than FK888 alone. CONCLUSIONS: These findings suggest that WIN 55,212-2 inhibits C-fiber activation via the cannabinoid CB2 receptor and thus suppresses antigen-induced inflammation in guinea pig airways.


Assuntos
Antígenos/imunologia , Benzoxazinas/farmacologia , Agonistas de Receptores de Canabinoides , Permeabilidade Capilar/efeitos dos fármacos , Morfolinas/farmacologia , Naftalenos/farmacologia , Hipersensibilidade Respiratória/metabolismo , Traqueia/metabolismo , Animais , Antígenos/administração & dosagem , Benzoxazinas/uso terapêutico , Canfanos/farmacologia , Antagonistas de Receptores de Canabinoides , Permeabilidade Capilar/imunologia , Dipeptídeos/farmacologia , Azul Evans/administração & dosagem , Azul Evans/metabolismo , Extravasamento de Materiais Terapêuticos e Diagnósticos/imunologia , Extravasamento de Materiais Terapêuticos e Diagnósticos/metabolismo , Extravasamento de Materiais Terapêuticos e Diagnósticos/prevenção & controle , Cobaias , Imunização , Indóis/farmacologia , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/prevenção & controle , Masculino , Morfolinas/uso terapêutico , Naftalenos/uso terapêutico , Antagonistas dos Receptores de Neurocinina-1 , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/antagonistas & inibidores , Hipersensibilidade Respiratória/tratamento farmacológico , Hipersensibilidade Respiratória/imunologia , Rimonabanto , Traqueia/irrigação sanguínea , Traqueia/efeitos dos fármacos
7.
Pediatr Allergy Immunol ; 20(5): 486-92, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19210644

RESUMO

The onset of asthma may be related to Th2 cytokine dominance at the time when food allergies occur several months after birth. This study investigated the effectiveness of early intervention with a Th2 cytokine inhibitor (suplatast tosilate) for prevention of asthma in infants with food allergies and atopic dermatitis. Suplatast tosilate dry syrup (6 mg/kg daily) or a histamine H(1)-blocker (ketotifen fumarate dry syrup: 0.06 mg/kg daily) was administered randomly to 53 infants with atopic dermatitis caused by food allergies. The primary endpoints were the incidence of asthma and the time to the onset of wheezing. The peripheral blood Th1/Th2 ratio, total IgE level, and eosinophil count were measured before and after treatment. After 24 months of treatment, the prevalence of asthma was significantly lower in the suplatast group (20.8%) than in the ketotifen group (65.6%, p < 0.01). Additionally, the time from the start of treatment to the initial episode of wheezing for infants who developed asthma was significantly longer in the suplatast group than the ketotifen group (p < 0.01). Furthermore, the eosinophil count was significantly decreased by suplatast treatment (p < 0.05), and there was a significant difference between the suplatast and ketotifen groups with respect to both the eosinophil count (p < 0.01) and the Th1/Th2 ratio (p < 0.05). The results of the present pilot study suggest that suplatast tosilate is useful for the primary prevention of wheezing and asthma in children.


Assuntos
Antialérgicos , Sulfonatos de Arila , Asma/prevenção & controle , Dermatite Atópica , Hipersensibilidade Alimentar , Hipersensibilidade Imediata/prevenção & controle , Sons Respiratórios/efeitos dos fármacos , Compostos de Sulfônio , Alérgenos/efeitos adversos , Alérgenos/imunologia , Animais , Antialérgicos/administração & dosagem , Antialérgicos/uso terapêutico , Sulfonatos de Arila/administração & dosagem , Sulfonatos de Arila/uso terapêutico , Asma/epidemiologia , Quimioprevenção , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/etiologia , Clara de Ovo/efeitos adversos , Feminino , Hipersensibilidade Alimentar/complicações , Hipersensibilidade Alimentar/tratamento farmacológico , Hipersensibilidade Alimentar/etiologia , Humanos , Incidência , Lactente , Cetotifeno/farmacologia , Cetotifeno/uso terapêutico , Masculino , Leite/efeitos adversos , Leite/imunologia , Projetos Piloto , Compostos de Sulfônio/administração & dosagem , Compostos de Sulfônio/uso terapêutico , Células Th1/imunologia , Células Th2/imunologia , Fatores de Tempo , Resultado do Tratamento
8.
Nihon Kokyuki Gakkai Zasshi ; 46(10): 842-6, 2008 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-19044037

RESUMO

A 47-year-old man visited his family doctor because of chronic productive cough. Though there were no abnormal chest X-ray film findings, he was diagnosed as tuberculosis on the basis of a sputum examination. Therefore, he was introduced to our hospital and as tracheobronchial tuberculosis was diagnosed by the bronchofiberscopic findings, showing ulceration with a white nodules from the lower part of trachea to the left main bronchus. By treatment, the ulcer change was improved, but the left main bronchus narrowed to pinhole size. Furthermore, the flow-volume curve became worse, and stridor appeared. We inserted Dumon stent in the left main bronchus 4 months later. As a result, his symptoms and flow-volume curve were improved, and we removed the stent 4 years and 6 months later. In this valuable case, we could observe the progress of the post-tuberculosis bronchial stenosis respiratory physiologically.


Assuntos
Brônquios/patologia , Broncopatias/terapia , Stents , Tuberculose/terapia , Broncopatias/complicações , Broncopatias/fisiopatologia , Doença Crônica , Constrição Patológica , Tosse/etiologia , Feminino , Seguimentos , Humanos , Curvas de Fluxo-Volume Expiratório Máximo , Pessoa de Meia-Idade , Espirometria , Resultado do Tratamento , Tuberculose/complicações , Tuberculose/fisiopatologia
9.
Evolution ; 62(8): 2065-79, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18507741

RESUMO

Flightlessness in insects is generally thought to have evolved due to changes in habitat environment or habitat isolation. Loss of flight may have changed reproductive traits in insects, but very few attempts have been made to assess evolutionary relationships between flight and reproductive traits in a group of related species. We elucidated the evolutionary history of flight loss and its relationship to evolution in food habit, relative reproductive investment, and egg size in the Silphinae (Coleoptera: Silphidae). Most flight-capable species in this group feed primarily on vertebrate carcasses, whereas flightless or flight-dimorphic species feed primarily on soil invertebrates. Ancestral state reconstruction based on our newly constructed molecular phylogenetic tree implied that flight muscle degeneration occurred twice in association with food habit changes from necrophagy to predatory, suggesting that flight loss could evolve independently from changes in the environmental circumstances per se. We found that total egg production increased with flight loss. We also found that egg size increased with decreased egg number following food habit changes in the lineage leading to predaceous species, suggesting that selection for larger larvae intensified with the food habit change. This correlated evolution has shaped diverse life-history patterns among extant species of Silphinae.


Assuntos
Evolução Biológica , Besouros/genética , Besouros/fisiologia , Comportamento Alimentar , Reprodução , Animais , Tamanho Corporal , DNA/genética , Primers do DNA/química , Ecologia , Meio Ambiente , Estágios do Ciclo de Vida , Modelos Biológicos , Nucleotídeos/química , Filogenia , Especificidade da Espécie
10.
J Hazard Mater ; 154(1-3): 287-93, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18162302

RESUMO

The objective of this study is to assess the applicability of a commercial magnesium oxide (MgO) and a composite material containing MgO and natural minerals ('MgO-SH-A') as the soil amendments for suppression of cadmium (Cd) uptake and accumulation into rice grains. Firstly, the mineralogical and physicochemical properties, soil neutralizing capacities and Cd sorption characteristics of these materials were investigated. Both materials were strongly alkaline and possessed large surface areas. The X-ray diffraction pattern of MgO-SH-A indicated the presence of MgO and a magnesium-silicate mineral (antigorite) as the main components. MgO-SH-A showed a milder soil neutralizing capacity as compared to commercial MgO. The sorptions of Cd on commercial MgO and MgO-SH-A both fitted Langmuir isotherm. The maximum Cd sorption capacity of commercial MgO (46.8 mmol g(-1) DW) was higher than that of MgO-SH-A (5.87 mmol g(-1) DW), although the latter material showed higher affinity to Cd as compared to the former one. The dominant reaction involved in the Cd sorptions was suggested to be precipitation of Cd(OH)2 on the material surface. About 40% of Cd sorbed on MgO-SH-A was resistant to desorption by 0.1 M HCl, implying that this portion was strongly retained on the material surface.


Assuntos
Cádmio/metabolismo , Grão Comestível/metabolismo , Óxido de Magnésio/química , Oryza/metabolismo , Poluentes do Solo/metabolismo , Adsorção , Cádmio/química , Poluentes do Solo/química
11.
J Hazard Mater ; 154(1-3): 294-9, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18054161

RESUMO

The objective of this study is to assess the applicability of a commercial magnesium oxide (MgO) and a composite material containing MgO and natural minerals ('MgO-SH-A') as the soil amendments for suppression of cadmium (Cd) uptake and accumulation into rice grains. A cultivation experiment of rice plants (Oryza sativa L. cv. Kinuhikari) was conducted in an actual Cd-contaminated alluvial paddy field to evaluate the effectiveness of these materials. The 'plant available' fractions of Cd in the paddy soil significantly decreased by application of commercial MgO at 2250 kg ha(-1) or MgO-SH-A at 4500 kg ha(-1). These decreases would be primarily attributed to the increase in soil pH due to applications of the MgO materials because these soil Cd fractions were significantly negatively correlated with the soil pH. Even under a suppressive condition for Cd uptake by rice plants, i.e., continuous flooding of the paddy field around the heading stage, applications of these materials further reduced Cd concentration in brown rice as compared to that from the control. It was concluded that the two MgO materials examined would be effective in preventing Cd contamination of rice grains grown in Cd-polluted paddy fields.


Assuntos
Cádmio/metabolismo , Grão Comestível/metabolismo , Óxido de Magnésio/química , Oryza/metabolismo , Poluentes do Solo/metabolismo , Concentração de Íons de Hidrogênio
12.
Nihon Kokyuki Gakkai Zasshi ; 45(3): 277-81, 2007 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-17419443

RESUMO

We report a case of pulmonary proteinosis detected at an early stage and followed up on chest CT. A 49-year-old man underwent detailed examinations because of abnormal shadows on chest CT taken on a routine medical examination. The chest CT revealed almost symmetrical ground glass opacities (GGOs) in both lungs with thickened alveolar septa. We could not make a definitive diagnosis even with bronchoalveolar lavage and transbronchial lung biopsy, but after about half a year, the GGOs increased. VATS-biopsy demonstrated alveoli filled with PAS-positive granular materials, and we made a diagnosis of pulmonary alveolar proteinosis. This case was found at an early stage and we were then able to follow up the disease.


Assuntos
Triagem Multifásica , Proteinose Alveolar Pulmonar/diagnóstico por imagem , Alvéolos Pulmonares/patologia , Tomografia Computadorizada por Raios X , Biópsia , Humanos , Masculino , Pessoa de Meia-Idade , Proteinose Alveolar Pulmonar/patologia , Radiografia Torácica , Cirurgia Torácica Vídeoassistida
13.
Metabolism ; 56(1): 44-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17161225

RESUMO

A C825T polymorphism of the gene encoding the G-protein beta3 subunit (GNB3) is associated with increased intracellular signal transduction. We know that this C825T polymorphism may influence hypertension and obesity. In whites, the C825T polymorphism has been reported to induce hypertension, obesity, and diabetic nephropathy. Thus, we investigated how genetic variation in the GNB3 gene is associated with hypertension, obesity, insulin resistance, diabetes, diabetic complications, and diabetic therapies in 427 Japanese subjects with type 2 diabetes mellitus and in 368 Japanese subjects who underwent general health examinations. The frequency of the GNB3 gene polymorphism was 0.48 and 0.47 in subjects with diabetes and in those who had general health examinations, respectively. The amount of hyperlipidemia of the CT allele was significantly lower than the amount in the CC allele in the Japanese subjects with diabetes. Our results suggest that the C825T polymorphism influences lipid metabolism and is not associated with hypertension, obesity, insulin resistance, diabetes, diabetic complications, or diabetic therapies.


Assuntos
Diabetes Mellitus/genética , Proteínas Heterotriméricas de Ligação ao GTP/genética , Hipertensão/genética , Resistência à Insulina/genética , Obesidade/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Glicemia/metabolismo , Índice de Massa Corporal , Colesterol/sangue , DNA/química , DNA/genética , Ácidos Graxos não Esterificados/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único
15.
Int Arch Allergy Immunol ; 141(1): 31-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16804322

RESUMO

BACKGROUND: Although neurogenic inflammation via the activation of C-fibers in the airway may have an important role in the pathogenesis of asthma, their regulatory mechanism remains uncertain. OBJECTIVE: The pharmacological profiles of a neuroactive steroid, allotetrahydrocorticosterone, on the activation of C-fibers in airway tissues were investigated, and the mechanism how a neuroactive steroid regulates airway inflammatory reactions was clarified. METHODS: The effects of allotetrahydrocorticosterone on electrical field stimulation-induced bronchial smooth muscle contraction in guinea pig airway tissues were investigated. The influences of K+ channel blockers and intracellular protein inhibitors on the effects of allotetrahydrocorticosterone were examined. RESULTS: Allotetrahydrocorticosterone dose-dependently inhibited electrical field stimulation-induced guinea pig bronchial smooth muscle contraction. The inhibitory effects of allotetrahydrocorticosterone on electrical field stimulation-induced bronchial contraction were reduced by the pretreatment of Maxi-K+ channel blockers, iberiotoxin and charybdotoxin, but not other K+ channel blockers, dendrotoxin or glibenclamide. Pretreatment with pertussis toxin diminished the inhibitory effect of allotetrahydrocorticosterone, but not an adenylate cyclase inhibitor, SQ 22536, nor a specific inhibitor of mitogen-activated protein kinase kinase, PD 98059. CONCLUSIONS: These findings suggest that allotetrahydrocorticosterone negatively modulates the activation of C-fibers in guinea pig airway tissues via the opening of Maxi-K+ channels and a pertussis toxin-sensitive G-protein-coupled mechanism.


Assuntos
Brônquios/efeitos dos fármacos , Corticosterona/análogos & derivados , Canais de Potássio Ativados por Cálcio de Condutância Alta/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Neurônios Aferentes/efeitos dos fármacos , Animais , Brônquios/inervação , Brônquios/metabolismo , Corticosterona/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Proteínas de Ligação ao GTP/efeitos dos fármacos , Proteínas de Ligação ao GTP/metabolismo , Cobaias , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/inervação , Músculo Liso/metabolismo , Neurônios Aferentes/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia
16.
Pharmacology ; 76(4): 157-62, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16446560

RESUMO

We examined the effects of cannabinoid receptor agonists on (45)Ca(2+) uptake in rat brain synaptosomes. A cannabinoid receptor agonist, (R)-(+)-[2,3-dihydro-5-methyl-3-[(4-merpholino)methyl]pyrrolo-[1,2,3-de]-1,4-benzoxazin-6-yl](1-naphthyl)methanone (WIN 55212-2) dose-dependently inhibited (45)Ca(2+) uptake in rat synaptosomes. Only an endogenous cannabinoid receptor agonist, anandamide, dose-dependently inhibited (45)Ca(2+) uptake in rat synaptosomes, but not an endogenous cannabinoid receptor agonist, palmitoylethanolamide. Only a cannabinoid CB1 antagonist, [N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamidehydrochloride] (SR 141716A), reversed the inhibitory effect of these WIN 55212-2 and anandamide on (45)Ca(2+) uptake in rat synaptosomes, but not a cannabinoid CB2 receptor antagonist, [N-[(1S)-endo-1,3,3-trimethylbicyclo[2.2.1]heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)pyrazole-3-carboxamide] (SR 144528). The inhibitory effects of WIN 55212-2 and anandamide on (45)Ca(2+) uptake in rat synaptosomes were reversed by the pretreatment of a voltage-sensitive A-type K(+) channel blocker, dendrotoxin, but no other type of K(+) channel blockers, i.e. iberiotoxin, charybdotoxin or glibenclamide. These findings suggest that cannabinoid receptors inhibit Ca(2+) influx into rat brain nerves via the activation of CB1 receptors and the opening of voltage-sensitive A-type K(+) channels.


Assuntos
Encéfalo/metabolismo , Cálcio/metabolismo , Agonistas de Receptores de Canabinoides , Sinaptossomos/efeitos dos fármacos , Amidas , Animais , Benzoxazinas , Transporte Biológico , Encéfalo/ultraestrutura , Canfanos/farmacologia , Antagonistas de Receptores de Canabinoides , Relação Dose-Resposta a Droga , Venenos Elapídicos/farmacologia , Endocanabinoides , Etanolaminas , Técnicas In Vitro , Masculino , Morfolinas/farmacologia , Naftalenos/farmacologia , Ácidos Palmíticos/farmacologia , Piperidinas/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Pirazóis/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/antagonistas & inibidores , Rimonabanto , Sinaptossomos/metabolismo
17.
Int Arch Allergy Immunol ; 138(1): 80-7, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16103691

RESUMO

BACKGROUND: Although neurogenic inflammation via the activation of C fibers in the airway must have an important role in the pathogenesis of asthma, their regulatory mechanism remains uncertain. OBJECTIVE: The pharmacological profiles of endogenous cannabinoid receptor agonists on the activation of C fibers in airway tissues were investigated and the mechanisms how cannabinoids regulate airway inflammatory reactions were clarified. METHODS: The effects of endogenous cannabinoid receptor agonists on electrical field stimulation-induced bronchial smooth muscle contraction, capsaicin-induced bronchoconstriction and capsaicin-induced substance P release in guinea pig airway tissues were investigated. The influences of cannabinoid receptor antagonists and K+ channel blockers to the effects of cannabinoid receptor agonists on these respiratory reactions were examined. RESULTS: Both endogenous cannabinoid receptor agonists, anandamide and palmitoylethanolamide, inhibited electrical field stimulation-induced guinea pig bronchial smooth muscle contraction, but not neurokinin A-induced contraction. A cannabinoid CB2 antagonist, SR 144528, reduced the inhibitory effect of endogenous agonists, but not a cannabinoid CB1 antagonist, SR 141716A. Inhibitory effects of agonists were also reduced by the pretreatment of large conductance Ca2+ -activated K+ channel (maxi-K+ channel) blockers, iberiotoxin and charybdotoxin, but not by other K+ channel blockers, dendrotoxin or glibenclamide. Anandamide and palmitoylethanolamide blocked the capsaicin-induced release of substance P-like immunoreactivity from guinea pig airway tissues. Additionally, intravenous injection of palmitoylethanolamide dose-dependently inhibited capsaicin-induced guinea pig bronchoconstriction, but not neurokinin A-induced reaction. However, anandamide did not reduce capsaicin-induced guinea pig bronchoconstriction. CONCLUSIONS: These findings suggest that endogenous cannabinoid receptor agonists inhibit the activation of C fibers via cannabinoid CB2 receptors and maxi-K+ channels in guinea pig airways.


Assuntos
Brônquios/efeitos dos fármacos , Agonistas de Receptores de Canabinoides , Fibras Nervosas Amielínicas/efeitos dos fármacos , Inflamação Neurogênica/prevenção & controle , Receptores de Canabinoides/efeitos dos fármacos , Amidas , Animais , Ácidos Araquidônicos/farmacologia , Brônquios/inervação , Broncoconstrição/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Canfanos/farmacologia , Capsaicina/toxicidade , Estimulação Elétrica , Endocanabinoides , Etanolaminas , Cobaias , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Inflamação Neurogênica/etiologia , Técnicas de Cultura de Órgãos , Ácidos Palmíticos/farmacologia , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas , Bloqueadores dos Canais de Potássio/farmacologia , Pirazóis/farmacologia , Rimonabanto , Substância P/biossíntese , Substância P/efeitos dos fármacos
18.
Neurosci Res ; 53(2): 210-5, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16055215

RESUMO

We examined the effects of a neuroactive steroid, allotetrahydrocorticosterone on the activation of capsaicin-sensitive afferent sensory nerves (C-fibers). Allotetrahydrocorticosterone (0.0001-1.0 microg/ml) dose-dependently inhibited electrical field stimulation-induced guinea-pig bronchial smooth muscle contraction, but not the substance P-induced contraction at 1.0 microg/ml. Allotetrahydrocorticosterone (0.01-1.0 microg/ml) also reduced the capsaicin-induced release of substance P-like immunoreactivity from guinea-pig airway tissues in a dose-dependent manner. The inhibitory effect of allotetrahydrocorticosterone on electrical field stimulation-induced bronchial contraction were reduced by the pretreatment of voltage-dependent K+ channel blockers, tetraethylammonium (1 mM). This evidence suggests that allotetrahydrocorticosterone negatively modulate the activation of C-fibers and substance P release from their endings in airway tissues via the opening of voltage-dependent K+ channels.


Assuntos
Brônquios/efeitos dos fármacos , Corticosterona/análogos & derivados , Neurônios Aferentes/efeitos dos fármacos , Animais , Corticosterona/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica , Estimulantes Ganglionares/farmacologia , Cobaias , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Neurônios Aferentes/metabolismo , Técnicas de Cultura de Órgãos , Canais de Potássio de Abertura Dependente da Tensão da Membrana/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , Substância P/metabolismo
19.
J Pharmacol Sci ; 98(1): 77-82, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15888960

RESUMO

We examined the effects of a cannabinoid receptor agonist, (R)-(+)-[2,3-dihydro-5-methyl-3-[(4-merpholino)methyl]pyrrolo-[1,2,3-de]-1,4-benzoxazin-6-yl](1-naphthyl)methanone (WIN 55212-2), on various respiratory reactions induced by the activation of capsaicin-sensitive afferent sensory nerves (C-fibers). WIN 55212-2 significantly inhibited capsaicin-induced guinea pig bronchoconstriction, but not the neurokinin A-induced reaction. Intravenous injection of WIN 55212-2 also blocked cigarette smoke-induced rat tracheal plasma extravasation. However, substance P-induced rat tracheal plasma extravasation was not affected by the administration of WIN 55212-2. A cannabinoid CB(2) receptor antagonist, {N-[(1S)-endo-1,3,3-trimethylbicyclo[2.2.1] heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)pyrazole-3-carboxamide} (SR 144528) reduced the inhibitory effects of WIN 55212-2, but not a cannabinoid CB(1) antagonist, [N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamidehydrochloride] (SR 141716A). A Maxi-K(+) channel opener, 1-(2'-hydroxy-5'-trifluoromethylphenyl)-5-trifluoromethyl-2(3H)benzimidazolone (NS 1619), specifically inhibited capsaicin-induced guinea pig bronchoconstriction and cigarette smoke-induced rat tracheal plasma extravasation. These findings suggest that WIN 55212-2 inhibits the activation of C-fibers via cannabinoid CB(2) receptors and Maxi-K(+) channels and reduces airway neurogenic inflammatory reactions in vivo.


Assuntos
Broncoconstrição/efeitos dos fármacos , Morfolinas/farmacologia , Naftalenos/farmacologia , Inibição Neural/efeitos dos fármacos , Receptor CB2 de Canabinoide/agonistas , Traqueia/efeitos dos fármacos , Animais , Benzoxazinas , Broncoconstrição/fisiologia , Cobaias , Masculino , Fibras Nervosas Amielínicas/efeitos dos fármacos , Fibras Nervosas Amielínicas/fisiologia , Inibição Neural/fisiologia , Ratos , Ratos Wistar , Receptor CB2 de Canabinoide/fisiologia , Traqueia/fisiologia
20.
Regul Pept ; 123(1-3): 161-5, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15518907

RESUMO

We compared the relaxant effect of original pituitary adenylate cyclase-activating peptide (PACAP)1-27 with that of a newly developed, synthetic PACAP1-27 analogue, [Arg15,20,21 Leu17]-PACAP-Gly-Lys-Arg-NH2, in human bronchi in vitro (n=4-5 in each group). Using precontraction by carbachol (0.1 microM), cumulative administration of PACAP1-27 and salbutamol caused concentration-dependent smooth muscle relaxation with similar potencies and maximum relaxant effects. Non-cumulative administration of the PACAP1-27 analogue and the original PACAP1-27 caused concentration-dependent relaxation with a similar maximum relaxant effect and potency as well. However, the onset and offset of action was markedly slower for the PACAP1-27 analogue than for the original PACAP1-27 (>90% versus <10% of peak relaxation remaining 5 h after administration). Peptidase inhibition by captopril (10 microM) and phosphoramidon (1 microM) significantly increased the maximum relaxant effect and duration of action of PACAP1-27 but not of the PACAP1-27 analogue, during the 3 h of observation in the human bronchi. We conclude that [Arg15,20,21 Leu17]-PACAP-Gly-Lys-Arg-NH2 produces significant concentration-dependent and sustained bronchial smooth muscle relaxation in vitro. The sustained relaxant effect is due, at least in part, to the synthetic PACAP1-27 analogue being less susceptible to cleavage by peptidases than the original peptide PACAP1-27.


Assuntos
Brônquios/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Fatores de Crescimento Neural/farmacologia , Neuropeptídeos/farmacologia , Neurotransmissores/farmacologia , Sequência de Aminoácidos , Brônquios/fisiologia , Humanos , Técnicas In Vitro , Dados de Sequência Molecular , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/fisiologia , Fatores de Crescimento Neural/química , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/fisiologia , Neuropeptídeos/química , Neuropeptídeos/genética , Neuropeptídeos/fisiologia , Neurotransmissores/química , Neurotransmissores/genética , Neurotransmissores/fisiologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase
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