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1.
Int J Occup Saf Ergon ; 28(3): 1787-1792, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34082647

RESUMO

Objectives. This study aimed to evaluate visual display terminal (VDT)-related digital eye strain (ES) and dry eye disease (DED) symptoms in subjects whose work was changed to teleworking (TW) during the coronavirus pandemic. Methods. A digital self-reported survey was conducted on subjects in TW, including demographics, medical history, VDT time and ES-related symptoms before and during the pandemic and DED (dry eye questionnaire 5 [DEQ-5] questionnaire). Results. A total of 1797 questionnaires were analyzed. Mean age was 40.5 (SD 11.1) years, and 69.9% were female. The mean number of TW weeks was 10.2 (SD 3.0). The total VDT total hours increased from 7.4 (SD 3.3) to 9.5 (SD 3.3) (p < 0.001). All ES symptoms presented a significant increase (p < 0.001). The mean DEQ-5 score was 8.3 (SD 4.9). The oldest group presented lower values, and women had a higher score (p < 0.001). Additionally, 28.6% of the subjects were classified with severe DED, and the variables associated with a logistic regression model were total VDT hours, female gender, refractive surgery, rosacea, depression, previous DED, keratoconus and blepharitis. Conclusions. The number of VDT hours seemed to be a relevant factor for increase in ES symptoms and a high prevalence of DED during the pandemic period.


Assuntos
Coronavirus , Síndromes do Olho Seco , Adulto , Estudos Transversais , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/epidemiologia , Feminino , Humanos , Masculino , Pandemias , Inquéritos e Questionários , Teletrabalho
2.
J Food Biochem ; 43(12): e13062, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31571257

RESUMO

Metabolic Syndrome (MS) is related to increased risk of early death due to cardiovascular complications, among others. Dietary intervention has been suggested as the safest and most cost-effective alternative for treatment of those alterations in patients with MS. The aim of this study was to investigate the effects of different egg white hydrolysates (HEW1 and HEW2) in obese Zucker rats, focus on the development of cardiovascular complications. Blood pressure, heart rate, basal cardiac function and vascular reactivity in aorta and mesenteric resistance arteries were evaluated. Reactive oxygen species production by dihydroethidium-emitted fluorescence, NOX-1 mRNA levels by qRT-PCR, angiotensin-converting enzyme activity by fluorimetry and kidney histopathology were also analysed. Both hydrolysates improve the endothelial dysfunction occurring in resistance arteries. Additionally, HEW2 reduced vascular oxidative stress. PRACTICAL APPLICATIONS: Egg white is a good source of bioactive peptides, some of them with high antioxidant activity. They may be used as functional foods ingredients and could serve as an alternative therapeutic option to decrease some Metabolic Syndrome-related complications. This study suggests that these hydrolysates could be an interesting non-pharmacological tool to control cardiovascular complications related to Metabolic Syndrome.


Assuntos
Antioxidantes/metabolismo , Aorta/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Clara de Ovo/química , Artérias Mesentéricas/efeitos dos fármacos , Obesidade/complicações , Estresse Oxidativo/efeitos dos fármacos , Hidrolisados de Proteína/metabolismo , Animais , Ratos , Ratos Zucker
3.
Food Chem Toxicol ; 133: 110799, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31493463

RESUMO

Aluminum (Al) is toxic for humans and animals. Here, we have tested the potential for Egg White Hydrolysate (EWH) to protect against cardiovascular changes in rats exposed to both high and low dietary levels of Al. Indeed, EWH has been previously shown to improve cardio metabolic dysfunctions induced by chronic exposure to heavy metals. Male Wistar rats received orally: Group 1) Low aluminum level (AlCl3 at a dose of 8.3 mg/kg b.w. during 60 days) with or without EWH treatment (1 g/kg/day); Group 2) High aluminum level (AlCl3 at a dose of 100 mg/kg b.w. during 42 days) with or without EWH treatment. After Al treatment, rats co-treated with EWH did not show vascular dysfunction or increased blood pressure as was observed in non EWH-cotreated animals. Indeed, co-treatment with EWH prevented the following effects observed in both aorta and mesenteric arteries: the increased vascular responses to phenylephrine (Phe), the decreased ACh-induced relaxation, the reduction on endothelial modulation of vasoconstrictor responses and the nitric oxide bioavailability, as well as the increased reactive oxygen species production from NAD(P)H oxidase. Altogether, our results suggest that EWH could be used as a protective agent against the harmful vascular effects after long term exposure to Al.


Assuntos
Antioxidantes/farmacologia , Proteínas do Ovo/farmacologia , Clara de Ovo/química , Hidrolisados de Proteína/farmacologia , Doenças Vasculares/prevenção & controle , Alumínio , Animais , Antioxidantes/química , Ciclo-Oxigenase 2/metabolismo , Proteínas do Ovo/química , Endotélio Vascular/efeitos dos fármacos , Hidrólise , Masculino , NADPH Oxidases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Tromboxano-A Sintase/metabolismo , Doenças Vasculares/induzido quimicamente , Vasoconstrição/efeitos dos fármacos
4.
Eur J Oncol Nurs ; 30: 75-83, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29031317

RESUMO

PURPOSE: This study analyses the premise that less time spent carrying out valuable activities and inflexible avoidance of thoughts, feelings and memories related to the oncological process may play an important role in the emotional problems of cancer survivors. METHODS: Emotional state was evaluated, as was quality of life and psychological flexibility in a sample of 122 breast cancer survivors (Mage = 52.40; SDage = 7.26). The analysis was carried out using a cross-sectional predictive study. RESULTS: Approximately half of those in the sample suffered from clinically significant emotional distress. The predictor variables selected explained a high percentage of the variability in emotional problems and quality of life (51.10-77.10%). CONCLUSION: Avoidance explained a high percentage of the variance in anxiety, depression and general distress. A lower degree of participation in valuable activities contributed, more specifically, to explaining variability in depression. The quantity and availability of environmental reinforcement was closely related to quality of life. A decisive contribution towards promoting emotional well-being and quality of life can be made by nursing action aimed at diminishing those avoidance strategies related to the oncological experience which may distance patients from daily activities which are gratifying and congruent with their values.


Assuntos
Adaptação Psicológica , Neoplasias da Mama/psicologia , Sobreviventes de Câncer/psicologia , Emoções , Qualidade de Vida/psicologia , Estresse Psicológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade
5.
Toxicology ; 390: 10-21, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28826906

RESUMO

Aluminum (Al) is a non-essential metal and a significant environmental contaminant and is associated with a number of human diseases including cardiovascular disease. We investigated the effects of Al exposure at doses similar to human dietary levels on the cardiovascular system over a 60day period. Wistar male rats were divided into two major groups and received orally: 1) Low aluminum level - rats were subdivided and treated for 60days as follows: a) Untreated - ultrapure water; b) AlCl3 at a dose of 8.3mg/kg bw for 60days, representing human Al exposure by diet; and 2) High aluminum level - rats were subdivided and treated for 42days as follows: C) Untreated - ultrapure water; d) AlCl3 at 100mg/kg bw for 42days, representing a high level of human exposure to Al. Effects on systolic blood pressure (SBP) and vascular function of aortic and mesenteric resistance arteries (MRA) were studied. Endothelium and smooth muscle integrity were evaluated by concentration-response curves to acetylcholine (ACh) and sodium nitroprusside. Vasoconstrictor responses to phenylephrine (Phe) in the presence and absence of endothelium and in the presence of the NOS inhibitor L-NAME, the potassium channels blocker TEA, the NAD(P)H oxidase inhibitor apocynin, superoxide dismutase (SOD), the non-selective COX inhibitor indomethacin and the selective COX-2 inhibitor NS 398 were analyzed. Vascular reactive oxygen species (ROS), lipid peroxidation and total antioxidant capacity, were measured. The mRNA expressions of eNOS, NAD(P)H oxidase 1 and 2, SOD1, COX-2 and thromboxane A2 receptor (TXA-2 R) were also investigated. Al exposure at human dietary levels impaired the cardiovascular system and these effects were almost the same as Al exposure at much higher levels. Al increased SBP, decreased ACh-induced relaxation, increased response to Phe, decreased endothelial modulation of vasoconstrictor responses, the bioavailability of nitric oxide (NO), the involvement of potassium channels on vascular responses, as well as increased ROS production from NAD(P)H oxidase and contractile prostanoids mainly from COX-2 in both aorta and mesenteric arteries. Al exposure increased vascular ROS production and lipid peroxidation as well as altered the antioxidant status in aorta and MRA. Al decreased vascular eNOS and SOD1 mRNA levels and increased the NAD(P)H oxidase 1, COX-2 and TXA-2 R mRNA levels. Our results point to an excess of ROS mainly from NAD(P)H oxidase after Al exposure and the increased vascular prostanoids from COX-2 acting in concert to decrease NO bioavailability, thus inducing vascular dysfunction and increasing blood pressure. Therefore, 60-day chronic exposure to Al, which reflects common human dietary Al intake, appears to pose a risk for the cardiovascular system.


Assuntos
Compostos de Alumínio/toxicidade , Pressão Sanguínea/efeitos dos fármacos , Cloretos/toxicidade , Ciclo-Oxigenase 2/metabolismo , Dieta , Endotélio Vascular/efeitos dos fármacos , Hipertensão/induzido quimicamente , NADH NADPH Oxirredutases/metabolismo , Vasoconstrição/efeitos dos fármacos , Cloreto de Alumínio , Animais , Inibidores de Ciclo-Oxigenase 2/farmacologia , Relação Dose-Resposta a Droga , Endotélio Vascular/enzimologia , Endotélio Vascular/fisiopatologia , Humanos , Hipertensão/enzimologia , Hipertensão/genética , Hipertensão/fisiopatologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , NADH NADPH Oxirredutases/antagonistas & inibidores , NADH NADPH Oxirredutases/genética , NADPH Oxidase 1 , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Receptores de Tromboxano A2 e Prostaglandina H2/efeitos dos fármacos , Receptores de Tromboxano A2 e Prostaglandina H2/genética , Receptores de Tromboxano A2 e Prostaglandina H2/metabolismo , Medição de Risco , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Fatores de Tempo
6.
Toxicol Appl Pharmacol ; 313: 109-118, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27984129

RESUMO

AIMS: Aluminum (Al) is an important environmental contaminant; however, there are not enough evidences of Al-induced cardiovascular dysfunction. We investigated the effects of acute exposure to aluminum chloride (AlCl3) on blood pressure, vascular reactivity and oxidative stress. METHODS AND RESULTS: Male Wistar rats were divided into two groups: Untreated: vehicle (ultrapure water, ip) and AlCl3: single dose of AlCl3 (100mg/kg,ip). Concentration-response curves to phenylephrine in the absence and presence of endothelium, the nitric oxide synthase inhibitor l-NAME, the potassium channel blocker tetraethylammonium, and the NADPH oxidase inhibitor apocynin were performed in segments from aortic and mesenteric resistance arteries. NO released was assessed in aorta and reactive oxygen species (ROS), malondialdehyde, non-protein thiol levels, antioxidant capacity and enzymatic antioxidant activities were investigated in plasma, aorta and/or mesenteric arteries. After one hour of AlCl3 exposure serum Al levels attained 147.7±25.0µg/L. Al treatment: 1) did not affect blood pressure, heart rate and vasodilator responses induced by acetylcholine or sodium nitroprusside; 2) decreased phenylephrine-induced vasoconstrictor responses; 3) increased endothelial modulation of contractile responses, NO release and vascular ROS production from NADPH oxidase; 4) increased plasmatic, aortic and mesenteric malondialdehyde and ROS production, and 5) decreased antioxidant capacity and affected the antioxidant biomarkers non-protein thiol levels, glutathione peroxidase, glutathione-S-transferase, superoxide dismutase and catalase enzymatic activities. CONCLUSION: AlCl3-acute exposure reduces vascular reactivity. This effect is associated with increased NO production, probably acting on K+ channels, which seems to occur as a compensatory mechanism against Al-induced oxidative stress. Our results suggest that Al exerts toxic effects to the vascular system.


Assuntos
Alumínio/toxicidade , Artérias/efeitos dos fármacos , Resistência Vascular , Animais , Artérias/metabolismo , Artérias/fisiologia , Masculino , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
7.
BMJ Case Rep ; 20152015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26677150

RESUMO

A 50-year-old patient, a smoker, was admitted to the hospital, with a solitary scalp lump. Subcutaneous lumps of the scalp are common but usually benign; however, the painless lump in our patient turned out to be a malignant osteolytic lesion of the skull. Frontal bone was involved, and the disease had spread to the dura. Neuroimaging showed osteolytic lesions involving the axial skeleton, skull and several vertebrae. MRI showed the involvement of the second cervical vertebra, which prompted us to start treatment with dexamethasone. Since the spinal cord was not involved, Oncologists decided not to start radiotherapy treatment until we had reached the final diagnosis. A frontal bone biopsy confirmed the diagnosis of lung carcinoma. Chest X-ray did not identify the pulmonary nodule, but CT scan revealed a 1 cm peripheral, spiculated, pulmonary nodule within a pathological parenchyma (severe diffuse pulmonary emphysema).


Assuntos
Osso Frontal/patologia , Neoplasias Pulmonares/diagnóstico , Nódulo Pulmonar Solitário/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Diagnóstico Diferencial , Evolução Fatal , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade , Couro Cabeludo/patologia , Nódulo Pulmonar Solitário/patologia
8.
Arch Bronconeumol ; 49(9): 383-7, 2013 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-23791383

RESUMO

BACKGROUND: Anaemia is one of the extrapulmonary manifestations of chronic obstructive pulmonary disease (COPD). Its real prevalence, physiopathology and clinical repercussion are unknown. The objectives of our study were: to determine the prevalence of anaemia in patients with stable COPD not attributable to other causes and to establish the relationship of anaemia with clinical, prognostic and inflammatory markers with an important role in COPD. METHODS: The study included stable COPD patients with no other known causes of anaemia. The following tests were carried out: respiratory function tests; serum determination of erythropoietin and inflammatory markers: high sensitivity C-reactive protein (hs-CRP), fibrinogen, interleukin 6 (IL-6), interleukin 8 (IL-8) and tumour necrosis factor α (TNF-α). Body mass index (BMI), Charlson and BODE indices, the number of exacerbations in the previous year, dyspnoea and quality of life were also calculated. RESULTS: One hundred and thirty patients were included. Anaemia prevalence was 6.2%. Mean haemoglobin value in anaemic patients was 11.9±0.95g/dL. Patients with anaemia had a lower BMI (P=.03), higher Charlson index (P=.002), more elevated erythropoietin levels (P=.016), a tendency to present a lower FEV1% value (P=.08) and significantly lower IL-6 values when compared to non-anaemic patients (P=.003). CONCLUSIONS: In our series, the anaemia associated with COPD was less prevalent than that published in the literature to date, and was related to certain clinical and inflammatory markers.


Assuntos
Anemia/epidemiologia , Doença Pulmonar Obstrutiva Crônica/sangue , Idoso , Anemia/sangue , Anemia/etiologia , Biomarcadores , Proteína C-Reativa/análise , Citocinas/sangue , Índices de Eritrócitos , Feminino , Ferritinas/sangue , Fibrinogênio/análise , Hematócrito , Hemoglobinas/análise , Humanos , Inflamação , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Doença Pulmonar Obstrutiva Crônica/complicações , Índice de Gravidade de Doença , Espanha/epidemiologia , Transferrina/análise
9.
Toxicol Appl Pharmacol ; 262(1): 22-31, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22546088

RESUMO

Seven day exposure to a low concentration of lead acetate increases nitric oxide bioavailability suggesting a putative role of K+ channels affecting vascular reactivity. This could be an adaptive mechanism at the initial stages of toxicity from lead exposure due to oxidative stress. We evaluated whether lead alters the participation of K+ channels and Na+/K+)-ATPase (NKA) on vascular function. Wistar rats were treated with lead (1st dose 4 µg/100 g, subsequent doses 0.05 µg/100g, im, 7 days) or vehicle. Lead treatment reduced the contractile response of aortic rings to phenylephrine (PHE) without changing the vasodilator response to acetylcholine (ACh) or sodium nitroprusside (SNP). Furthermore, this treatment increased basal O2⁻ production, and apocynin (0.3 µM), superoxide dismutase (150 U/mL) and catalase (1000 U/mL) reduced the response to PHE only in the treated group. Lead also increased aortic functional NKA activity evaluated by K+-induced relaxation curves. Ouabain (100 µM) plus L-NAME (100 µM), aminoguanidine (50 µM) or tetraethylammonium (TEA, 2 mM) reduced the K+-induced relaxation only in lead-treated rats. When aortic rings were precontracted with KCl (60 mM/L) or preincubated with TEA (2 mM), 4-aminopyridine (4-AP, 5 mM), iberiotoxin (IbTX, 30 nM), apamin (0.5 µM) or charybdotoxin (0.1 µM), the ACh-induced relaxation was more reduced in the lead-treated rats. Additionally, 4-AP and IbTX reduced the relaxation elicited by SNP more in the lead-treated rats. Results suggest that lead treatment promoted NKA and K+ channels activation and these effects might contribute to the preservation of aortic endothelial function against oxidative stress.


Assuntos
Aorta/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Canais de Potássio/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Aorta/patologia , Endotélio Vascular/patologia , Masculino , Nitroprussiato/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/metabolismo , Fenilefrina/farmacologia , Canais de Potássio/metabolismo , Ratos , Ratos Wistar , ATPase Trocadora de Sódio-Potássio/metabolismo , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
10.
Med Clin (Barc) ; 139(2): 47-53, 2012 Jun 16.
Artigo em Espanhol | MEDLINE | ID: mdl-22401725

RESUMO

BACKGROUND AND OBJECTIVES: Smoking creates an inflammation that leads to lose of lung function. Tumor necrosis factor alpha (TNF-α) is a cytokine that plays an important role in the pathogenesis of chronic obstructive pulmonary disease. There is a need to develop methods for an early detection of an impaired lung function in smokers. We aimed to show that smokers have higher levels of TNF-α in serum and exhaled breath condensate (EBC). We also analysed the influence of sex, age and weight on TNF-α, and determined the association between smoking, pulmonary function and TNF-α. PATIENTS AND METHODS: Prospective study of smokers and non-smokers without any known disease. Respiratory function tests, EBC and blood samples were performed before smoking cessation. STATISTICAL ANALYSIS: SPSS 11.0. RESULTS: Fifty-one patients (60.8% smokers), 56.9% females, mean age 39.88 years old. Smokers initiated at an age of 15.77 years; the mean of cigarettes/day was 21.68. Significant differences in TNF-α serum levels between smokers and non-smokers were observed (P<.043). Differences did not reach significance for EBC. For tobacco consumption data, only age at smoking initiation and serum TNF-α levels had a correlation. A significant relation between TNF-α serum levels and forced expiratory volume in one second and forced vital capacity was found. CONCLUSIONS: Smokers show higher TNF-α levels in serum. Number of years of smoking has an influence on TNF-α levels. There is a modest correlation between pulmonary function and plasma TNF-α levels, but not for EBC.


Assuntos
Inflamação/sangue , Inflamação/etiologia , Fumar/efeitos adversos , Fumar/sangue , Fator de Necrose Tumoral alfa/sangue , Adulto , Biomarcadores/sangue , Diagnóstico Precoce , Feminino , Humanos , Inflamação/diagnóstico , Masculino , Estudos Prospectivos
11.
Regul Pept ; 120(1-3): 253-60, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15177944

RESUMO

OBJECTIVE: We analyse the effect of aldosterone on vasomotor response induced by electrical field stimulation (EFS) in mesenteric arteries from Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR). RESULTS: Aldosterone (0.001-1 microM) reduced vasoconstrictor response to EFS in a dose- and time-dependent manner only in SHR. Thus, the rest of experiments were performed only in SHR. Aldosterone did not affect either noradrenaline response or release. Effect of aldosterone (1 microM) on EFS response was not affected by NG-nitro-arginine-methyl esther (100 microM), and was abolished by capsaicin (0.5 microM) and the calcitonin gene-related peptide antagonist (CGRP 8-37, 0.5 microM). Calcitonin gene-related peptide (0.1 nM-0.1 microM) induced a concentration-dependent relaxation, which was enhanced by aldosterone (1 microM). Incubation with either spironolactone (1 microM), glibenclamide (10 microM), RU 486 10 microM, ODQ (10 microM) or cycloheximide (10 microM) significantly reduced the enhancement of CGRP-relaxation produced by aldosterone, while remained unmodified by SQ 22,536. CONCLUSIONS: Aldosterone decreases the vasoconstrictor response to EFS in mesenteric arteries from SHR but not from WKY. This effect is mediated by an increased response to the sensory neurotransmitter CGRP, substantially, through glucocorticoid receptors activation. Furthermore, this effect is mediated by an increase of cGMP synthesis and ATP-dependent potassium channel activation.


Assuntos
Adenina/análogos & derivados , Aldosterona/farmacologia , Peptídeo Relacionado com Gene de Calcitonina/fisiologia , Hipertensão/metabolismo , Neurônios/fisiologia , Sistema Vasomotor/fisiologia , Adenina/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Antiarrítmicos/farmacologia , Capsaicina/farmacologia , GMP Cíclico/metabolismo , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Glibureto/farmacologia , Hipertensão/patologia , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/inervação , Antagonistas de Receptores de Mineralocorticoides/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Norepinefrina/metabolismo , Canais de Potássio/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptores de Glucocorticoides/metabolismo , Espironolactona/farmacologia , Vasoconstrição/fisiologia
12.
Eur J Pharmacol ; 487(1-3): 167-73, 2004 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-15033389

RESUMO

The aim of this study was to analyse the possible influence of cyclic AMP-protein kinase A (cAMP-PKA) activation on neuronal nitric oxide (NO) release induced by electrical field stimulation in mesenteric arteries from Wistar Kyoto (WKY) rats. Western blot experiments demonstrated the expression of neuronal NO synthase (nNOS) in mesenteric artery from WKY rats; however, electrical field stimulation alone did not induce detectable NO release. Preincubation with forskolin allowed NO release induced by electrical field stimulation, which was abolished by: the neuronal toxine tetrodotoxin, the nNOS inhibitors 7-nitroindazole or N(omega)-propil-l-arginine (NPLA), and the PKA inhibitors N-(2-(p-Bromocinnamylamino) ethyl 5-isoquinolinesulfonamide hydrochloride (H-89) or (9R,10S,12S)-2,3,9,10,11, 12-Hexahydro-10-9-methyl-1-oxo-9,12-epoxy-1H-diindolo(1,2,3-fg:3,2,1k)pyrrolo(3,4-l)(1,6) benzodiazocine-10-carboxylic acid hexyl ester (KT-5720). Preincubation with prostacyclin also allowed the NO release induced by electrical field stimulation which was significantly decreased by: the neuronal toxine tetrodotoxin, the nNOS inhibitors 7-nitroindazole or NPLA, and the PKA inhibitors H-89 or KT-5720. The NOS inhibitor N(omega)-nitro-l-arginine methyl ester (l-NAME) did not modify the vasoconstrictor response induced by electrical field stimulation. However, in the presence of forskolin or prostacyclin, l-NAME increased the vasoconstrictor response to electrical field stimulation. These results indicate that forskolin and prostacyclin allow neuronal NO release induced by electrical field stimulation through a mechanism involving cAMP-PKA activation in rat mesenteric arteries.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/farmacologia , Artérias Mesentéricas/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Óxido Nítrico/metabolismo , Animais , Western Blotting , Colforsina/farmacologia , AMP Cíclico/metabolismo , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Epoprostenol/farmacologia , Técnicas In Vitro , Indazóis/farmacologia , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/enzimologia , NG-Nitroarginina Metil Éster/farmacologia , Neurônios/fisiologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo I , Ratos , Ratos Endogâmicos WKY
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