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1.
Sci Total Environ ; 912: 169060, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38061642

RESUMEN

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.


Asunto(s)
Cryptomeria , Cryptomeria/fisiología , Transpiración de Plantas/fisiología , Bosques , Árboles/fisiología , Agua
2.
BMJ Case Rep ; 12(1)2019 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-30635311

RESUMEN

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.


Asunto(s)
Síndrome Antifosfolípido/complicaciones , Rivaroxabán/uso terapéutico , Tromboembolia Venosa/etiología , Trombosis de la Vena/etiología , Cuidados Posteriores , Síndrome Antifosfolípido/sangre , Síndrome Antifosfolípido/patología , Inhibidores del Factor Xa/uso terapéutico , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Humanos , Masculino , Persona de Mediana Edad , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/tratamiento farmacológico , Embolia Pulmonar/etiología , Recurrencia , Rivaroxabán/administración & dosificación , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Tromboembolia Venosa/diagnóstico por imagen , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/tratamiento farmacológico
3.
Exp Ther Med ; 14(4): 3233-3238, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28928804

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-22627847

RESUMEN

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.


Asunto(s)
Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Asma/etiología , Resfriado Común/complicaciones , Antagonistas de Leucotrieno/uso terapéutico , Antiasmáticos/administración & dosificación , Asma/epidemiología , Niño , Preescolar , Resfriado Común/epidemiología , Progresión de la Enfermedad , Femenino , Humanos , Antagonistas de Leucotrieno/administración & dosificación , Masculino , Prevalencia , Resultado del Tratamiento
5.
Biol Pharm Bull ; 33(10): 1763-5, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20930390

RESUMEN

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.


Asunto(s)
Broncodilatadores/farmacocinética , Medicamentos Genéricos/farmacocinética , Absorción Cutánea , Piel/metabolismo , Terbutalina/análogos & derivados , Parche Transdérmico , Animales , Asma/tratamiento farmacológico , Broncodilatadores/administración & dosificación , Modelos Animales de Enfermedad , Medicamentos Genéricos/administración & dosificación , Femenino , Patentes como Asunto , Ratas , Ratas Sprague-Dawley , Terbutalina/administración & dosificación , Terbutalina/farmacocinética
6.
Int Arch Allergy Immunol ; 152(3): 295-300, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20150748

RESUMEN

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.


Asunto(s)
Antígenos/inmunología , Benzoxazinas/farmacología , Agonistas de Receptores de Cannabinoides , Permeabilidad Capilar/efectos de los fármacos , Morfolinas/farmacología , Naftalenos/farmacología , Hipersensibilidad Respiratoria/metabolismo , Tráquea/metabolismo , Animales , Antígenos/administración & dosificación , Benzoxazinas/uso terapéutico , Canfanos/farmacología , Antagonistas de Receptores de Cannabinoides , Permeabilidad Capilar/inmunología , Dipéptidos/farmacología , Azul de Evans/administración & dosificación , Azul de Evans/metabolismo , Extravasación de Materiales Terapéuticos y Diagnósticos/inmunología , Extravasación de Materiales Terapéuticos y Diagnósticos/metabolismo , Extravasación de Materiales Terapéuticos y Diagnósticos/prevención & control , Cobayas , Inmunización , Indoles/farmacología , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/prevención & control , Masculino , Morfolinas/uso terapéutico , Naftalenos/uso terapéutico , Antagonistas del Receptor de Neuroquinina-1 , Ovalbúmina/administración & dosificación , Ovalbúmina/inmunología , Piperidinas/farmacología , Pirazoles/farmacología , Receptor Cannabinoide CB1/antagonistas & inhibidores , Receptor Cannabinoide CB2/antagonistas & inhibidores , Hipersensibilidad Respiratoria/tratamiento farmacológico , Hipersensibilidad Respiratoria/inmunología , Rimonabant , Tráquea/irrigación sanguínea , Tráquea/efectos de los fármacos
7.
Pediatr Allergy Immunol ; 20(5): 486-92, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19210644

RESUMEN

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.


Asunto(s)
Antialérgicos , Arilsulfonatos , Asma/prevención & control , Dermatitis Atópica , Hipersensibilidad a los Alimentos , Hipersensibilidad Inmediata/prevención & control , Ruidos Respiratorios/efectos de los fármacos , Compuestos de Sulfonio , Alérgenos/efectos adversos , Alérgenos/inmunología , Animales , Antialérgicos/administración & dosificación , Antialérgicos/uso terapéutico , Arilsulfonatos/administración & dosificación , Arilsulfonatos/uso terapéutico , Asma/epidemiología , Quimioprevención , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/etiología , Clara de Huevo/efectos adversos , Femenino , Hipersensibilidad a los Alimentos/complicaciones , Hipersensibilidad a los Alimentos/tratamiento farmacológico , Hipersensibilidad a los Alimentos/etiología , Humanos , Incidencia , Lactante , Cetotifen/farmacología , Cetotifen/uso terapéutico , Masculino , Leche/efectos adversos , Leche/inmunología , Proyectos Piloto , Compuestos de Sulfonio/administración & dosificación , Compuestos de Sulfonio/uso terapéutico , Células TH1/inmunología , Células Th2/inmunología , Factores de Tiempo , Resultado del Tratamiento
8.
Nihon Kokyuki Gakkai Zasshi ; 46(10): 842-6, 2008 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-19044037

RESUMEN

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.


Asunto(s)
Bronquios/patología , Enfermedades Bronquiales/terapia , Stents , Tuberculosis/terapia , Enfermedades Bronquiales/complicaciones , Enfermedades Bronquiales/fisiopatología , Enfermedad Crónica , Constricción Patológica , Tos/etiología , Femenino , Estudios de Seguimiento , Humanos , Curvas de Flujo-Volumen Espiratorio Máximo , Persona de Mediana Edad , Espirometría , Resultado del Tratamiento , Tuberculosis/complicaciones , Tuberculosis/fisiopatología
9.
Evolution ; 62(8): 2065-79, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18507741

RESUMEN

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.


Asunto(s)
Evolución Biológica , Escarabajos/genética , Escarabajos/fisiología , Conducta Alimentaria , Reproducción , Animales , Tamaño Corporal , ADN/genética , Cartilla de ADN/química , Ecología , Ambiente , Estadios del Ciclo de Vida , Modelos Biológicos , Nucleótidos/química , Filogenia , Especificidad de la Especie
10.
J Hazard Mater ; 154(1-3): 294-9, 2008 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-18054161

RESUMEN

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.


Asunto(s)
Cadmio/metabolismo , Grano Comestible/metabolismo , Óxido de Magnesio/química , Oryza/metabolismo , Contaminantes del Suelo/metabolismo , Concentración de Iones de Hidrógeno
11.
J Hazard Mater ; 154(1-3): 287-93, 2008 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-18162302

RESUMEN

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.


Asunto(s)
Cadmio/metabolismo , Grano Comestible/metabolismo , Óxido de Magnesio/química , Oryza/metabolismo , Contaminantes del Suelo/metabolismo , Adsorción , Cadmio/química , Contaminantes del Suelo/química
12.
Nihon Kokyuki Gakkai Zasshi ; 45(3): 277-81, 2007 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-17419443

RESUMEN

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.


Asunto(s)
Tamizaje Multifásico , Proteinosis Alveolar Pulmonar/diagnóstico por imagen , Alveolos Pulmonares/patología , Tomografía Computarizada por Rayos X , Biopsia , Humanos , Masculino , Persona de Mediana Edad , Proteinosis Alveolar Pulmonar/patología , Radiografía Torácica , Cirugía Torácica Asistida por Video
13.
Metabolism ; 56(1): 44-8, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17161225

RESUMEN

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.


Asunto(s)
Diabetes Mellitus/genética , Proteínas de Unión al GTP Heterotriméricas/genética , Hipertensión/genética , Resistencia a la Insulina/genética , Obesidad/genética , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Glucemia/metabolismo , Índice de Masa Corporal , Colesterol/sangre , ADN/química , ADN/genética , Ácidos Grasos no Esterificados/sangre , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Insulina/sangre , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple
14.
Int Arch Allergy Immunol ; 141(1): 31-6, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16804322

RESUMEN

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.


Asunto(s)
Bronquios/efectos de los fármacos , Corticosterona/análogos & derivados , Canales de Potasio de Gran Conductancia Activados por el Calcio/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Neuronas Aferentes/efectos de los fármacos , Animales , Bronquios/inervación , Bronquios/metabolismo , Corticosterona/farmacología , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Inhibidores Enzimáticos/farmacología , Proteínas de Unión al GTP/efectos de los fármacos , Proteínas de Unión al GTP/metabolismo , Cobayas , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/inervación , Músculo Liso/metabolismo , Neuronas Aferentes/metabolismo , Bloqueadores de los Canales de Potasio/farmacología
16.
Pharmacology ; 76(4): 157-62, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16446560

RESUMEN

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.


Asunto(s)
Encéfalo/metabolismo , Calcio/metabolismo , Agonistas de Receptores de Cannabinoides , Sinaptosomas/efectos de los fármacos , Amidas , Animales , Benzoxazinas , Transporte Biológico , Encéfalo/ultraestructura , Canfanos/farmacología , Antagonistas de Receptores de Cannabinoides , Relación Dosis-Respuesta a Droga , Venenos Elapídicos/farmacología , Endocannabinoides , Etanolaminas , Técnicas In Vitro , Masculino , Morfolinas/farmacología , Naftalenos/farmacología , Ácidos Palmíticos/farmacología , Piperidinas/farmacología , Bloqueadores de los Canales de Potasio/farmacología , Pirazoles/farmacología , Ratas , Ratas Sprague-Dawley , Receptor Cannabinoide CB1/antagonistas & inhibidores , Receptor Cannabinoide CB2/antagonistas & inhibidores , Rimonabant , Sinaptosomas/metabolismo
17.
Neurosci Res ; 53(2): 210-5, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16055215

RESUMEN

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.


Asunto(s)
Bronquios/efectos de los fármacos , Corticosterona/análogos & derivados , Neuronas Aferentes/efectos de los fármacos , Animales , Corticosterona/farmacología , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Estimulantes Ganglionares/farmacología , Cobayas , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Neuronas Aferentes/metabolismo , Técnicas de Cultivo de Órganos , Canales de Potasio con Entrada de Voltaje/efectos de los fármacos , Compuestos de Amonio Cuaternario/farmacología , Sustancia P/metabolismo
18.
Int Arch Allergy Immunol ; 138(1): 80-7, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16103691

RESUMEN

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.


Asunto(s)
Bronquios/efectos de los fármacos , Agonistas de Receptores de Cannabinoides , Fibras Nerviosas Amielínicas/efectos de los fármacos , Inflamación Neurogénica/prevención & control , Receptores de Cannabinoides/efectos de los fármacos , Amidas , Animales , Ácidos Araquidónicos/farmacología , Bronquios/inervación , Broncoconstricción/efectos de los fármacos , Bloqueadores de los Canales de Calcio/farmacología , Canfanos/farmacología , Capsaicina/toxicidad , Estimulación Eléctrica , Endocannabinoides , Etanolaminas , Cobayas , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Inflamación Neurogénica/etiología , Técnicas de Cultivo de Órganos , Ácidos Palmíticos/farmacología , Piperidinas/farmacología , Alcamidas Poliinsaturadas , Bloqueadores de los Canales de Potasio/farmacología , Pirazoles/farmacología , Rimonabant , Sustancia P/biosíntesis , Sustancia P/efectos de los fármacos
19.
J Pharmacol Sci ; 98(1): 77-82, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15888960

RESUMEN

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.


Asunto(s)
Broncoconstricción/efectos de los fármacos , Morfolinas/farmacología , Naftalenos/farmacología , Inhibición Neural/efectos de los fármacos , Receptor Cannabinoide CB2/agonistas , Tráquea/efectos de los fármacos , Animales , Benzoxazinas , Broncoconstricción/fisiología , Cobayas , Masculino , Fibras Nerviosas Amielínicas/efectos de los fármacos , Fibras Nerviosas Amielínicas/fisiología , Inhibición Neural/fisiología , Ratas , Ratas Wistar , Receptor Cannabinoide CB2/fisiología , Tráquea/fisiología
20.
Regul Pept ; 123(1-3): 161-5, 2004 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-15518907

RESUMEN

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.


Asunto(s)
Bronquios/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Factores de Crecimiento Nervioso/farmacología , Neuropéptidos/farmacología , Neurotransmisores/farmacología , Secuencia de Aminoácidos , Bronquios/fisiología , Humanos , Técnicas In Vitro , Datos de Secuencia Molecular , Relajación Muscular/efectos de los fármacos , Músculo Liso/fisiología , Factores de Crecimiento Nervioso/química , Factores de Crecimiento Nervioso/genética , Factores de Crecimiento Nervioso/fisiología , Neuropéptidos/química , Neuropéptidos/genética , Neuropéptidos/fisiología , Neurotransmisores/química , Neurotransmisores/genética , Neurotransmisores/fisiología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa
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