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1.
Int. j. cardiovasc. sci. (Impr.) ; 32(3): 207-216, May-June 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1002224

RESUMO

Curcuma longa has biological effects. Its cardiovascular activities are yet to be scientifically studied. Objectives: To investigate the vasorelaxant effects of the aqueous extract of Curcuma longa (AECL). Methods: Aortic annuli of normotensive rats, with or without endothelium, were set up in a data storage system with nutrient solution in recipients, with scientifically recommended temperature, aeration and tension. Over contraction by Phenylephrine, the AECL (1, 3, 10, 30, 100, 300 and 1000 µg/mL) was incubated before and after incubation with atropine or L-name or indomethacin. An AECL concentration-response curve was also built over contractions caused by elevation of extracellular K+. Data were significant when p < 0.05, with GraphPad Prism 6.0 software resolutions. Results: The AECL induced 100% vasorelaxation also in the endothelium-free annuli. The part of the endothelium-dependent effect had EC50 = 4.32 ± 0.05 µg/mL. With inhibition of NO production, the EC50 increased to 126.50 ± 2.35 µg/mL; after inhibition of prostacyclin production, to 124.6 ± 0.05 µg/mL; and after muscarinic blockade, to 437.10 ± 0.2 µg/mL. Opening of K+ channels (relaxation of 56.98%) and VOCC blockade (relaxation of 31.56%) were evident. Conclusion: AECL induced significant vasorelaxation, being more significant in the presence of endothelium. The muscarinic pathway seems to be the main one involved in this effect, followed by the NO production and prostacyclin pathways. The activity in K+ channels by AECL was more significant than its VOCC blockade. The use of other models and tools to study action mechanisms will be important and elucidating


Assuntos
Animais , Ratos , Aorta , Fenilefrina , Curcuma/efeitos adversos , Ratos , Vasodilatadores/uso terapêutico , Cardiotônicos , Análise Estatística , Análise de Variância , Receptores Muscarínicos , Modelos Animais , Crocus , Hipertensão , Antioxidantes
2.
Int. j. cardiovasc. sci. (Impr.) ; 32(3): 207-216, may.-june. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1005799

RESUMO

Background:Curcuma longa has biological effects. Its cardiovascular activities are yet to be scientifically studied. Objectives: To investigate the vasorelaxant effects of the aqueous extract of Curcuma longa (AECL). Methods: Aortic annuli of normotensive rats, with or without endothelium, were set up in a data storage system with nutrient solution in recipients, with scientifically recommended temperature, aeration and tension. Over contraction by Phenylephrine, the AECL (1, 3, 10, 30, 100, 300 and 1000 µg/mL) was incubated before and after incubation with atropine or L-name or indomethacin. An AECL concentration-response curve was also built over contractions caused by elevation of extracellular K+. Data were significant when p < 0.05, with GraphPad Prism 6.0 software resolutions.Results: The AECL induced 100% vasorelaxation also in the endothelium-free annuli. The part of the endothelium-dependent effect had EC50 = 4.32 ± 0.05 µg/mL. With inhibition of NO production, the EC50 increased to 126.50 ± 2.35 µg/mL; after inhibition of prostacyclin production, to 124.6 ± 0.05 µg/mL; and after muscarinic blockade, to 437.10 ± 0.2 µg/mL. Opening of K+ channels (relaxation of 56.98%) and VOCC blockade (relaxation of 31.56%) were evident. Conclusion: AECL induced significant vasorelaxation, being more significant in the presence of endothelium. The muscarinic pathway seems to be the main one involved in this effect, followed by the NO production and prostacyclin pathways. The activity in K+ channels by AECL was more significant than its VOCC blockade. The use of other models and tools to study action mechanisms will be important and elucidating


Assuntos
Animais , Ratos , Aorta , Fenilefrina , Ratos , Curcuma , Vasodilatadores/uso terapêutico , Cardiotônicos , Análise Estatística , Análise de Variância , Receptores Muscarínicos , Modelos Animais , Crocus , Hipertensão , Antioxidantes
3.
Rev. cuba. oftalmol ; 32(1): e691, ene.-mar. 2019.
Artigo em Espanhol | LILACS | ID: biblio-1093679

RESUMO

RESUMEN Durante la cirugía de catarata, la inducción de la dilatación de la pupila (midriasis) y el mantenimiento de un grado adecuado de esta a lo largo de toda la operación son elementos críticos para la eliminación y el reemplazo exitoso del cristalino. Una pupila pequeña o un cierre pupilar durante la cirugía hacen que esta sea un desafío desde el punto de vista técnico y aumente el riesgo de complicaciones transquirúrgicas, por lo que una midriasis adecuada y mantenida ha permanecido hasta nuestros días como un pilar fundamental para maximizar la seguridad y los resultados refractivos de la cirugía de catarata moderna. Esta midriasis se consigue habitualmente con la aplicación previa de colirios anticolinérgicos y simpaticomiméticos, con los cuales el tiempo de espera para la dilatación pupilar es frecuentemente más largo que el procedimiento quirúrgico; tienen una significativa absorción sistémica que pueden aumentar el riesgo de efectos secundarios cardiovasculares, y el efecto midriático tiende a desaparecer durante la cirugía. Con el objetivo de acceder a la información actualizada sobre los fármacos midriáticos más usados de modo intracameral, sus dosis y formas de aplicación durante la cirugía de catarata, se realiza el presente trabajo de revisión(AU)


ABSTRACT In cataract surgery, induction and maintenance of an adequate degree of pupil dilation (mydriasis) throughout the operation are critical elements for the successful removal and replacement of the crystalline lens. A small pupil or pupil closure during surgery pose a technical challenge and increase the risk of intraoperative complications. This is the reason why adequate, maintained mydriasis has remained to this day a fundamental pillar to maximize both safety and satisfactory refractive results in modern cataract surgery. Mydriasis is normally achieved with the previous application of anticholinergic and sympathomimetic eye drops, for which the waiting time for pupil dilation is often longer than the surgical procedure, they have significant systemic absorption which may increase the risk of cardiovascular side effects, and the mydriatic effect tends to vanish during surgery. A bibliographic review was conducted with the purpose of accessing updated information about the most commonly used intracameral mydriatic drugs, their doses and modes of application during cataract surgery(AU)


Assuntos
Humanos , Fenilefrina/administração & dosagem , Extração de Catarata/efeitos adversos , Lidocaína/administração & dosagem , Midriáticos/uso terapêutico
4.
Braz. J. Pharm. Sci. (Online) ; 55: e18075, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1039056

RESUMO

The present study was designed to investigate the effect of early and late administration of phenylephrine during ischemia against regional ischemia-reperfusion injuries in an isolated rat heart model. All animals were randomly divided into experimental groups: (I) IR (Ischemic/ reperfusion): the hearts underwent 35 min of regional ischemia followed by 60 min of reperfusion; (II) 5HD-IR-0: the hearts were perfused for 5 min with 5HD (5-hydroxydecanoate, specific mKATP channel blocker, 100 µM) at the onset of regional ischemia; (III) 5HD-IR-20: the hearts were perfused for 5 min with 5HD 20 min after regional ischemia; (IV) PE-IR-10: the hearts were perfused for 5 min with phenylephrine 10 min after regional ischemia; (V) PE-IR-30: the hearts were perfused for 5 min with phenylephrine (100 µM) 30 min after regional ischemia; (VI) PE-5HD-IR-10 group: the hearts were perfused for 5 min with 5HD at the onset of regional ischemia after which phenylephrine was administrated as in group IV; and (VII) PE-5HD-IR-30: the hearts were perfused for 5 min with 5HD 20 min after the ischemia and then phenylephrine was administrated as in group V. The hemodynamic parameters were recorded throughout the experiment. Ischemia-induced arrhythmias, myocardial infarct size (IS), creatin kinase-MB isoenzyme (CK-MB), plasma lactate dehydrogenase (LDH) activities, and coronary blood flow (CBF) were measured in all animals. Perfusion of phenylephrine 30 min after the regional ischemia curtailed the myocardial infarct size, reduced CK-MB, and improved cardiac function and CBF. Administration of 5HD 30 min after the ischemia abolished cardioprotective effects of phenylephrine in the late phase. These results suggest the involvement of mKATP in the mechanism of phenylephrine-induced late preconditioning.


Assuntos
Animais , Masculino , Ratos , Fenilefrina/análise , Fenilefrina/efeitos adversos , Isquemia/tratamento farmacológico , Reperfusão
5.
Med. UIS ; 31(2): 33-39, mayo-ago. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1002508

RESUMO

Resumen Introducción: la hipotensión es el evento adverso más incidente cuando se administra anestesia subaracnoidea para cesárea; múltiples estrategias para su prevención y manejo se han propuesto, entre ellas el uso de vasopresores profilácticos con resultados no concluyentes. Objetivo: evaluar la eficacia preventiva del uso de Fenilefrina en la hipotensión arterial inducida por la anestesia subaracnoidea en gestantes llevadas a cesárea. Materiales y Métodos: ensayo clínico controlado, doble ciego, en gestantes, mayores de 18 años, ASA 1 y 2, quienes recibieron anestesia subaracnoidea para cesárea, fueron aleatorizadas a recibir placebo o infusión profiláctica de fenilefrina 40 mcg/min, durante 5 minutos. Resultados: se incluyeron 140 pacientes en el análisis de datos. La incidencia de hipotensión fue mayor en el grupo control que en el intervenido (RA 45,71% vs 32,85%). Sin presentarse diferencias significativas entre ambos grupos (p=0,119). RR de hipotensión en el grupo intervenido fueron menores, independiente del criterio de hipotensión (tensión arterial sistólica, RR 0,72 (IC95% 0,47-1,09); tensión arterial media, RR 0.93 (IC95% 0,64-1,37); TAS o TAM RR 0.86 (IC95% 0,62-1,21)), pero sin diferencias significativas p>0,05. El uso de vasopresores en los pacientes que presentaron este evento se dio en 75.4% (n=52), con RR mayor en el grupo control y diferencias significativas al evaluar los dos grupos. (RR: 1,4 p=0,032). Conclusiones: fenilefrina profiláctica no demostró ser eficaz en disminuir la incidencia de hipotensión; sin embargo, sí se asocia con una disminución significativa en los requerimientos de vasopresores, así como en la incidencia de náuseas y vómito. MÉD.UIS. 2018;31(2):33-9.


Abstract Background: Hypotension is the most common adverse event when subarachnoid anesthesia is administered for cesarean section; multiple strategies for its prevention and management have been proposed, including the use of prophylactic vasopressors with inconclusive results. Objective: To evaluate the preventive efficacy of the use of phenylephrine in hypotension induced by subarachnoid anesthesia in pregnant women taken to caesarean section. Methods: A double-blind, controlled clinical trial in pregnant women, older than 18 years old, ASA 1 and 2, who received a subarachnoid anesthesia for cesarean section, were randomized to receive placebo or prophylactic infusion of phenylephrine 40 mcg / min, for 5 minutes. Results: 140 patients were included in data analysis. Incidence of hypotension was higher in the control group than in the intervention group (AR 45.71% vs 32.85%). There were no significant differences between the two groups (p = 0.119). RR of hypotension in the intervention group were lower, independent of the criterion of hypotension [systolic blood pressure, RR 0.72 (95% CI 0.47-1.09), mean arterial pressure, RR 0.93 (95% CI 0.64-1.37), SBP or MAP 0.86 (RR 0.86) (IC95% 0.62-1.21)], but without significant differences p> 0.05. The use of vasopressors in patients who presented this event occurred in 75.4% (n = 52), with higher RR in the control group and significant differences when evaluating the two groups. (RR 1.4 p = 0.032). Conclusions: Prophylactic phenylephrine did not prove effective in reducing the incidence of hypotension, however, it is associated with a significant decrease in vasopressor requirements, as well as in the incidence of nausea and vomiting. MÉD.UIS. 2018;31(2):33-9.


Assuntos
Humanos , Feminino , Gravidez , Fenilefrina , Cesárea , Náusea e Vômito Pós-Operatórios , Hipotensão , Complicações Intraoperatórias , Raquianestesia
6.
Rev. bras. oftalmol ; 76(1): 28-32, Jan.-Feb. 2017. tab
Artigo em Português | LILACS | ID: biblio-844064

RESUMO

RESUMO Objetivo: Comparar a eficácia fenilefrina a 10% aplicada pelo próprio paciente por vaporização em olho fechado em relação à instilação de gota em olho aberto em indivíduos que irão realizar exame de fundoscopia e avaliar o nível de dificuldade e a adequação técnica entre os métodos de administração. Métodos: Ensaio clínico controlado, randomizado e pareado realizado em 2014 envolvendo 100 olhos de 50 pacientes na Policlínica Ronaldo Gazolla - RJ, sem doenças oculares ou sistêmicas que comprometiam a dilatação pupilar. Os pacientes foram submetidos à instilação de 1 gota de fenilefrina a 10% e aplicação de vaporizador do mesmo midriático no olho contralateral. O olho em que se instilou o colírio permaneceu aberto, enquanto o olho vaporizado ficou fechado durante as aplicações da medicação. O diâmetro pupilar foi medido antes da aplicação, 10, 20 e 30 minutos após. O processo de instilação ou vaporização foi observado quanto a sua adequação técnica por um dos autores. Após o processo foi perguntado ao paciente questões pré-formuladas sobre a praticidade de ambos os métodos. Resultados: A diferença de midríase média entre os grupos de olhos avaliados em um determinado tempo foi no máximo 0,3 mm , o que não foi clinicamente ou estatisticamente significativo (ANOVA: F = 1,97 e p = 0,163609) . Porém, ao longo do tempo, a diferença entre o diâmetro da pupila no tempo inicial e no tempo de 30 minutos foi 1,15 mm para os olhos vaporizados e 1,58 mm para os olhos instilados com gotas (ANOVA: F = 129,22 e p ≤ 0,0001). Percentual de 60% dos pacientes tocaram a ponta do frasco de colírio nos olhos, enquanto que 12% tocaram o orifício na ponta do vaporizador com os dedos (p < 0,000001). Setenta de dois por cento (72%) consideraram a instilação de gotas fácil ou muito fácil enquanto 62% consideraram a vaporização em olho fechado fácil ou muito fácil (p = 0,238). Conclusão: A instilação de gotas em olhos abertos e a vaporização de olhos fechados da fenilefrina a 10% apresentou eficácia clínica semelhante. A vaporização foi mais segura e apresentou nível de dificuldade um pouco maior do que a instilação, apesar dos pacientes serem experientes para instilar gotas e inexperientes para vaporizar a medicação em olho fechado.


ABSTRACT Objective: To compare the effectiveness of phenylephrine 10% applied by a spray onto the eye closed over drop instillation onto an open eye on patients who will perform ophthalmoscopy and assess the level of difficulty and technical adequacy of the administration methods. Methods: The study was a clinical trial, controlled, randomized and paired, performed in 2014, involving 100 eyes of 50 patients in the Polyclinic Ronaldo Gazolla - RJ, with no ocular or systemic diseases that compromised the pupillary dilation. Patients underwent 10% phenylephrine eye drop instillation onto one open eye and spray application onto the other eye, which was closed. Pupillary diameter was measured before application and 10, 20, 30 minutes after. The process of instillation or vaporization was observed for its technical correctness by one of the authors. A questionnaire was asked to the patient about the difficulty of both methods after topical administration. Results: The average mydriasis difference between the eye groups assessed at a given time was at most 0.3 mm, which was not clinically or statistically significant (ANOVA: F = 1.97 and p = 0.163609). However, over time, the difference between the average pupil diameter before application and after 30 minutes was 1.15 mm to vaporized eyes and to 1.58 mm in eyes instilled with drops (ANOVA: F = 129, 22 and p ≤ 0.0001). Sixty per cent of patients touched the tip of the eye drop bottle onto the eye, while 12% touched the tip of the vaporizer with their fingers (p <0.000001). Seventy two percent (72%) considered the drops instillation easy or very easy, while 62% considered vaporization in a closed eye easy or very easy (p = 0.238). Conclusion: The instillation of drops phenylephrine 10% in open eyes and the vaporization onto closed eyes showed similar clinical efficacy. Vaporization was safer and a little more difficult than instillation, despite the patients being experienced for instilling drops and inexperienced to vaporize the medication in a closed eye.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Administração Tópica , Olho/efeitos dos fármacos , Midriáticos/administração & dosagem , Soluções Oftálmicas/administração & dosagem , Fenilefrina , Instilação de Medicamentos , Ensaio Clínico Controlado Aleatório , Inquéritos e Questionários
7.
Vitae (Medellín) ; 24(1): 30-37, 2017. Ilustraciones
Artigo em Inglês | LILACS, COLNAL | ID: biblio-994473

RESUMO

The treatment of symptoms of prostatic hyperplasia is among the traditional uses of Achyrocline bogotensis (Kunth) [N.V. "Vira Vira", Compositae] in Colombia. Pharmacological therapy for this disorder depends mainly on alpha-1 antiadrenergic agents, and the mechanism has not been studied previously using A. bogotensis. Objectives: To assess the alpha-1 antiadrenergic effect of the extract obtained from the aerial parts of A. bogotensis in isolated aortic rings from Wistar rats. Methods: The study compared the effects of the ethanol extract of A. bogotensis, prazosin (reference) and DMSO (control) in rings stimulated with phenylephrine (PE) or KCl. The capacity to reduce the PE pressor effect by the ethanol extract (pD2' value) was determined. To quantify the A. bogotensis relaxant potency, increasing concentrations of the ethanol extract (0.1 µg/mL-0.1 mg/mL), were added cumulatively to isolated aortic rings pre-contracted with PE (0.1 µM) or KCl (80 mM). To explore the possible participation of nitric oxide (NO), L-NAME (100 µM) was administered to aortic rings exposed to cumulatively increasing concentrations of PE in isolated aortic rings in the presence of the extract (10 µg/mL). Aqueous, butanol and dichloromethane fractions (10 µg/mL) obtained from the ethanol extract were assayed. Phytochemical screening was also performed. Results: Prazosin and A. bogotensis extract notably reduced the contraction induced by PE whereas their inhibitory effect in rings contracted with KCl were lower. A. bogotensis ethanol extract showed a high capacity for reducing the PE pressor response (pD´2: 5.51) as well as total efficacy for relaxing rings previously precontracted with PE. The relaxant efficacy and potency of A. bogotensis extract against rings previously contracted with KCl were notably lower. L-NAME partly reverted the inhibitory effect of A. bogotensis. Aqueous, butanol and dichloromethane fractions gave inhibitory responses lower than that obtained with the ethanol extract. Phytochemical screening of A. bogotensis extract revealed the significant presence of flavonoid and triterpene metabolites. Conclusions: These results suggest that A. bogotensis elicits a smooth muscle relaxant effect related to the alpha-1 antiadrenergic mechanism. This response is partially NO dependent and seems to be due to interactions among active metabolites likely to be of flavonoid and/or terpenoid nature.


Antecedentes: Uno de los usos tradicionales de la especie Achyrocline bogotensis (Kunth) [N.V. "Vira Vira", Compositae] en Colombia es el tratamiento de los síntomas de la hiperplasia prostática benigna. La terapia farmacológica de este trastorno se basa principalmente en el uso de agentes que ejercen efecto anti-adrenérgico alfa-1, mecanismo no estudiado previamente en esta especie. Objetivos: Evaluar el efecto anti-adrenérgico alfa-1 del extracto de la especie Achyrocline bogotensis (Kunth) en anillos aislados de aorta de ratas Wistar. Métodos: Se comparó el efecto del extracto etanólico de A. bogotensis, prazosin (patrón) y DMSO (control) en anillos aislados de aorta de ratas Wistar estimulados con fenilefrina (PE) o KCl. Se determinó la capacidad del extracto etanólico de A. bogotensis para reducir el efecto contráctil inducido por PE (pD'2 ). Se cuantificó la potencia relajante del extracto etanólico de A. bogotensis (0.1 µg/ mL - 0.1 mg/mL) en anillos de aorta previamente contraídos con PE (0.1 µM) o KCl (80 mM). Se exploró la posible participación del óxido nítrico (NO), administrando L-NAME (100 µM) en anillos de aorta expuestos a concentraciones acumulativas de PE en presencia del extracto etanólico (10 µg/mL). También se comparó el efecto de las fracciones acuosa, butanólica y diclometanólica (10 µg/mL), obtenidas del extracto etanólico, en anillos estimulados con PE. Además, se efectuó un tamizado fitoquímico del extracto. Resultados: Prazosin y el extracto de A. bogotensis redujeron notablemente el efecto de PE mientras su efecto inhibitorio sobre la contracción inducida por KCl fue menor. El extracto etanólico mostró una ostensible capacidad para reducir el efecto contráctil inducido por PE (pD2 ´: 5.51) así como una eficacia total para relajar anillos previamente contraídos con PE. La potencia y eficacia de relajación del extracto de A. bogotensis frente a anillos previamente contraídos con KCl fue notablemente menor. L-NAME revirtió parcialmente el efecto inhibitorio del extracto de A. bogotensis. Las fracciones acuosa, butanólica y diclorometanólica arrojaron respuestas inhibitorias menores que las inducidas por el extracto etanólico. El tamizado fitoquímico del extracto de A. bogotensis mostró la presencia de metabolitos de naturaleza flavonoide y terponoide. Conclusiones: Estos resultados muestran que la especie A. bogotensis ejerce efectos relajantes sobre el músculo liso vinculados con mecanismos de tipo antiadrenérgico alfa-1. Esta respuesta depende en parte de la presencia de NO y parece deberse a la interacción de metabolitos de naturaleza flavonoide y/o terpenoide.


Assuntos
Animais , Antagonistas Adrenérgicos , Achyrocline , Aorta , Fenilefrina , Flavonoides , Sintomas do Trato Urinário Inferior , Óxido Nítrico
8.
Arq. bras. cardiol ; 105(2): 160-167, Aug. 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-758002

RESUMO

AbstractBackground:Hypertension is a public health problem and increases the incidence of cardiovascular diseases.Objective:To evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of NG-nitro L-arginine methyl ester (L-NAME)-induced hypertensive rats.Methods:Wistar rats were divided into three groups: control (C), hypertensive (H), and exercised hypertensive (EH). Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN), potassium chloride (KCl) and sodium nitroprusside (SNP).Results:Rats treated with L-NAME showed an increase (p < 0.001) in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001) the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01) smooth muscle sensitivity to NPS was observed in group EH as compared to group H.Conclusion:One resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats.


ResumoFundamento:A hipertensão é um problema de saúde pública e faz aumentar a incidência das doenças cardiovasculares.Objetivo:Avaliar os efeitos de uma sessão de exercício resistido sobre os mecanismos contráteis e relaxantes do músculo liso vascular em artéria mesentérica de ratos hipertensos induzidos por L-NAME.Métodos:Ratos Wistar foram divididos em três grupos: Controle (C), Hipertenso (H) e Hipertenso Exercitado (HE). A hipertensão foi induzida pela administração de 20 mg/kg de NG-nitro L-arginina metil éster (L-NAME) durante sete dias antes dos protocolos experimentais. O protocolo de exercício resistido consistiu em dez séries de dez repetições e intensidade de 40% de uma repetição máxima. A reatividade do músculo liso vascular foi avaliada através de curvas concentração-resposta para a fenilefrina (FEN), cloreto de potássio (KCl) e nitroprussiato de sódio (NPS).Resultados:Os ratos tratados com L-NAME apresentaram aumento (p < 0,001) da Pressão Arterial Sistólica (PAS), da Pressão Arterial Diastólica (PAD) e da Pressão Arterial Média (PAM) quando comparados ao período inicial da indução. Não foi observada diferença na sensibilidade da FEN entre os grupos H e HE. O exercício resistido agudo reduziu (p < 0,001) a resposta contrátil induzida pelo KCl nas concentrações de 40 e 60 mM do grupo HE quando comparado ao grupo H. Foi observado maior (p < 0,01) sensibilidade do músculo liso ao NPS no grupo HE quando comparado ao grupo H.Conclusão:Uma sessão de exercício resistido reduz as respostas contráteis induzidas pelo KCl, além de aumentar a sensibilidade do músculo liso ao NO em artéria mesentérica de ratos hipertensos.


Assuntos
Animais , Tolerância ao Exercício/fisiologia , Hipertensão/fisiopatologia , Músculo Liso Vascular/fisiopatologia , Condicionamento Físico Animal/fisiologia , Peso Corporal , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Inibidores Enzimáticos/farmacologia , Artérias Mesentéricas/fisiopatologia , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Nitroprussiato/análise , Fenilefrina/análise , Cloreto de Potássio/análise , Ratos Wistar , Fatores de Tempo
9.
Braz. j. med. biol. res ; 48(6): 537-544, 06/2015. graf
Artigo em Inglês | LILACS | ID: lil-748218

RESUMO

Amfepramone (diethylpropion) is an appetite-suppressant drug used for the treatment of overweight and obesity. It has been suggested that the systemic and central activity of amfepramone produces cardiovascular effects such as transient ischemic attacks and primary pulmonary hypertension. However, it is not known whether amfepramone produces immediate vascular effects when applied in vitro to rat aortic rings and, if so, what mechanisms may be involved. We analyzed the effect of amfepramone on phenylephrine-precontracted rat aortic rings with or without endothelium and the influence of inhibitors or blockers on this effect. Amfepramone produced a concentration-dependent vasorelaxation in phenylephrine-precontracted rat aortic rings that was not affected by the vehicle, atropine, 4-AP, glibenclamide, indomethacin, clotrimazole, or cycloheximide. The vasorelaxant effect of amfepramone was significantly attenuated by NG-nitro-L-arginine methyl ester (L-NAME) and tetraethylammonium (TEA), and was blocked by removal of the vascular endothelium. These results suggest that amfepramone had a direct vasorelaxant effect on phenylephrine-precontracted rat aortic rings, and that inhibition of endothelial nitric oxide synthase and the opening of Ca2+-activated K+ channels were involved in this effect.


Assuntos
Animais , Masculino , Acetilcolina/farmacologia , Aorta Torácica/efeitos dos fármacos , Depressores do Apetite/farmacologia , Dietilpropiona/farmacologia , Vasodilatadores/farmacologia , Aorta Torácica/metabolismo , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/metabolismo , Endotélio Vascular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/metabolismo , Óxido Nítrico Sintase Tipo III/efeitos dos fármacos , Fenilefrina/farmacologia , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/metabolismo , Ratos Wistar , Tetraetilamônio/metabolismo , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos
10.
São Paulo; s.n; 2015. [139] p. ilus, tab, graf.
Tese em Português | LILACS | ID: biblio-870853

RESUMO

O objetivo primário do presente estudo foi quantificar e comparar as alterações do posicionamento da pálpebra superior nos olhos testados e nos olhos contralaterais de portadores de ptose palpebral senil submetidos à instilação de colírio de fenilefrina a 10% em um dos olhos e ao teste do levantamento manual da pálpebra ptótica. Como objetivo secundário, verificar a influência da dominância ocular, da intensidade e da uni ou bilateralidade da ptose nas respostas palpebrais frente aos dois testes. Métodos: Estudo clínico prospectivo transversal, que avaliou o efeito da ação tópica do colírio de fenilefrina a 10% e da manobra de levantamento manual da pálpebra no posicionamento palpebral de indivíduos portadores de ptose palpebral involucional unilateral ou bilateral. Os pacientes foram filmados antes e 5, 10 e 15 minutos após a instilação do colírio. A distância margem reflexo (DMR1) foi medida com a utilização do software Image J e os resultados foram analisados com o modelo linear de efeitos mistos. Resultados: Na pesquisa foram incluídos 70 indivíduos entre 44-86 anos, 64 destes do sexo feminino (91.43%), divididos em três grupos: indivíduos com ptose unilateral; com ptose bilateral e controles. O olho submetido à instilação do colírio de fenilefrina apresentou aumento da DMR1 nos primeiros 10 minutos: de 1,33±0,66 mm para 2,06±0,89 mm (grupo ptose unilateral), de 1,26 ± 0.63 mm para 2,29±0,86 mm (grupo ptose bilateral) e de 3,12 ± 0,68 mm para 4,06 ± 0,92 mm (grupo controle). A DMR1 diminuiu nos olhos contralaterais dos pacientes portadores de ptose, mais significativamente após a instilação do colírio de fenilefrina: teste de fenilefrina vs. levantamento manual da pálpebra = 18.9% vs. 17.2% de redução no grupo com ptose unilateral, e 13.6% vs. 10.7% de redução no grupo com ptose bilateral. Os fatores: dominância ocular, uni ou bilateralidade da ptose e a sua intensidade não influenciaram na resposta aos testes. Conclusões: O aumento da DMR1 ocorreu nos...


Purpose: The primary aim of this study is quantify and compare the effect of 10% phenylephrine instillation and manual elevation (ME) on the upper eyelid position of the tested eye and the contralateral eye in patients with involutional blepharoptosis (IB). The secondary objective is to correlate the eye dominance, severity and laterality of ptosis with eyelid position changes after these two tests. Methods: This is a prospective transversal study conducted in involutional ptosis patients, submitted to two tests followed by observation of the effect on the contralateral eyelid: 1) ME of the more ptotic eyelid, and 2) instillation of two drops of 10% PE (phenylephrine test) in the more ptotic eye. The patients were filmed before and 5, 10 and 15 minutes after instillation. The upper eyelid margin reflex distance (MRD1) was measured using the software Image J, and the results were analyzed with the linear mixed-effects model. Results: The study included 70 patients aged 44- 86 years, 64 of whom were female (91.43%), divided into three groups: subjects with unilateral ptosis, subjects with bilateral ptosis and controls. The eye submitted to instillation with 10% PE displayed significant elevation during the first 10 min: from 1.33±0.66mm to 2.06 ± 0.89mm (unilateral group), from 1.26 ± 0.63mm to 2.29 ± 0.86mm (bilateral group) and from 3.12 ± 0.68mm to 4.06±0.92mm (control group). MRD1 decreased in the contralateral eye in IB patients, significantly more so after the phenylephrine test: PE vs. ME = 18.9% vs. 17.2% reduction in the unilateral group, and 13.6% vs. 10.7% reduction in the bilateral group. The outcome was not influenced by IB severity and the concurrence of IB and eye dominance. Conclusion: MRD1 elevation in tested eyes in all groups. Both Manual elevation and phenylephrine tests affected the contralateral upper eyelid, but the response was significantly better with the latter.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Blefaroptose , Dominância Ocular , Pálpebras , Fenilefrina , Estudos Prospectivos
11.
Arq. bras. oftalmol ; 77(6): 377-381, Nov-Dec/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-735804

RESUMO

Purpose: To quantify and compare the effects of instillation with 10% phenylephrine and digital lifting on the contralateral upper eyelid of patients with involutional bilateral blepharoptosis. Methods: The present prospective clinical study involved patients with involutional bilateral blepharoptosis who underwent two tests: 1) digital lifting of the more ptotic eyelid and observation of the effect on the contralateral eyelid and 2) instillation of two drops of 10% phenylephrine in the more ptotic eye and observation of the effect on the contralateral eyelid. Patients were filmed before and 5, 10, and 15 min after instillation, and the resulting images were analyzed to obtain eyelid measurements. The results were tested using a linear mixed-effects model. Results: A total of 27 patients, ranging from 52 to 82 years of age (mean age 68.51 ± 8.21 years), 24 (88.88%) of whom were women, were included in the present study. In eyes that received instillation, the marginal distance reflex-1 (MDR1) values increased from baseline (1.21 ± 0.60 mm) until 10 min after instillation, then remained statistically unchanged until 15 min after instillation (2.42 ± 0.90 mm). Significant differences were observed in the contralateral eye of the group that underwent digital lifting (1.51 ± 0.53 mm - 1.63 ± 0.56 mm) and in the contralateral eye of the group that underwent 10% phenylephrine instillation (1.38 ± 0.54 mm - 1.63 ± 0.56 mm); p=0.02 and p<0.01, respectively. Conclusion: In all eyes, 10% phenylephrine elevated the upper eyelid, with improved eyelid height at 10 min after instillation. Significant differences were observed in the height of the contralateral eyelid when compared before and after each intervention in each group; however, this difference was very small and nearly undetectable by conventional clinical evaluation in the digital lifting group. However, the 10% phenylephrine eye-drop test resulted in substantial changes in MDR1 values ...


Objetivo: Quantificar e comparar o efeito da instilação do colírio de fenilefrina 10% com o levantamento manual da pálpebra superior contralateral de pacientes com ptose palpebral bilateral involucional. Métodos: Estudo clínico e prospectivo de pacientes com ptose palpebral bilateral involucional submetidos a dois testes: 1) elevação manual da pálpebra mais ptótica e observação do efeito da intervenção na pálpebra contralateral; e 2) a instilação de duas gotas de colírio de fenilefrina 10% no olho mais ptótico e observação do efeito da intervenção na pálpebra contralateral. Os pacientes foram filmados antes e 5, 10 e 15 minutos após a instilação. Os resultados foram analisados estatisticamente com o modelo linear de efeitos mistos. Resultados: O estudo incluiu 27 pacientes com idade entre 52-82 anos (68,51 ± 8,21), 24 dos quais eram do sexo feminino (88,88%). Em olhos submetidos a instilação do colírio, os valores da DMR1 (distância marginal reflexo) aumentaram da linha de base (1,21 ± 0,60 mm) até os 10 min, em seguida, manteve-se estatisticamente estável até 15 min (2,42 ± 0,90 mm). Diferenças significativas foram observadas nos olhos contralaterais, independentemente do levantamento manual da pálpebra (1,51 ± 0,53 mm - 1,63 ± 0,56 milímetros) e da instilação do colírio de fenilefrina 10% (1,38 ± 0,54 mm - 1,63 ± 0,56 mm), p=0,02 e p<0,01 respectivamente. Conclusões: Em todos os olhos, a instilação do colírio de fenilefrina 10% mostrou um aumento gradual do valor de distância marginal reflexo até os 10 min. Nos olhos contralaterais houve diminuição do valor de distância marginal reflexo, independentemente do teste realizado, porém as mudanças que ocorrem na posição da pálpebra contralateral, durante o teste da elevação manual, são muito pequenas e difíceis de serem detectadas no exame clínico convencional. Enquanto isso, o teste de colírio de fenilefrina 10% produziu mudanças substanciais nos valores distância marginal reflexo nos ...


Assuntos
Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Blefaroptose/terapia , Pálpebras/efeitos dos fármacos , Fenilefrina/administração & dosagem , Blefaroptose/patologia , Pálpebras/patologia , Instilação de Medicamentos , Soluções Oftálmicas/administração & dosagem , Estudos Prospectivos , Valores de Referência , Procedimentos Cirúrgicos Reconstrutivos/métodos , Fatores de Tempo , Resultado do Tratamento
12.
Acta cir. bras ; 29(11): 703-710, 11/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-728647

RESUMO

PURPOSE: To verify the effects of different catecholamines on volemic expansion and on the autonomic nervous system in rabbits that were subjected to hemorrhage. METHODS: Twenty four rabbits subjected to hemorrhage (with a 25% loss of blood volume) and were randomly divided into four experimental groups: 1) HEMO Group underwent replacement with their own blood in an equal volume; 2) SS Group underwent replacement with saline solution (SS) in a volume that corresponded to three times the removed blood volume; 3) ISP Group underwent replacement with SS and isoprenaline; 4) FNL Group underwent replacement with SS and phenylephrine. Spectral Analysis of the heart rate and heart rate variability were performed from the recorded data. Hematocrit was measured throughout the experiment. RESULTS: Replacement with SS and an α- or β-agonist did not produce differences in the intravascular retention compared to replacement with SS alone. An analysis of HRV showed that the FNL group maintained the LF/HF ratio better than ISP and SS. CONCLUSIONS: No difference in vascular retention when α- or β- agonists were added to SS during post-hemorrhagic recovery. The animals in the FNL group maintained the integrity of the autonomic response within normal physiological standards during hemorrhagic stress. .


Assuntos
Animais , Coelhos , Volume Sanguíneo/efeitos dos fármacos , Catecolaminas/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Hemorragia/fisiopatologia , Cloreto de Sódio/farmacologia , Agonistas de Receptores Adrenérgicos alfa 1/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Sistema Nervoso Autônomo/efeitos dos fármacos , Transfusão de Sangue Autóloga , Análise de Fourier , Hematócrito , Frequência Cardíaca/fisiologia , Hemorragia/etiologia , Hemorragia/terapia , Isoproterenol/farmacologia , Fenilefrina/farmacologia , Distribuição Aleatória , Valores de Referência , Reprodutibilidade dos Testes , Análise Espectral , Fatores de Tempo
13.
Braz. j. med. biol. res ; 47(10): 826-833, 10/2014. graf
Artigo em Inglês | LILACS | ID: lil-722174

RESUMO

O-GlcNAcylation is a modification that alters the function of numerous proteins. We hypothesized that augmented O-GlcNAcylation levels enhance myosin light chain kinase (MLCK) and reduce myosin light chain phosphatase (MLCP) activity, leading to increased vascular contractile responsiveness. The vascular responses were measured by isometric force displacement. Thoracic aorta and vascular smooth muscle cells (VSMCs) from rats were incubated with vehicle or with PugNAc, which increases O-GlcNAcylation. In addition, we determined whether proteins that play an important role in the regulation of MLCK and MLCP activity are directly affected by O-GlcNAcylation. PugNAc enhanced phenylephrine (PE) responses in rat aortas (maximal effect, 14.2±2 vs 7.9±1 mN for vehicle, n=7). Treatment with an MLCP inhibitor (calyculin A) augmented vascular responses to PE (13.4±2 mN) and abolished the differences in PE-response between the groups. The effect of PugNAc was not observed when vessels were preincubated with ML-9, an MLCK inhibitor (7.3±2 vs 7.5±2 mN for vehicle, n=5). Furthermore, our data showed that differences in the PE-induced contractile response between the groups were abolished by the activator of AMP-activated protein kinase (AICAR; 6.1±2 vs 7.4±2 mN for vehicle, n=5). PugNAc increased phosphorylation of myosin phosphatase target subunit 1 (MYPT-1) and protein kinase C-potentiated inhibitor protein of 17 kDa (CPI-17), which are involved in RhoA/Rho-kinase-mediated inhibition of myosin phosphatase activity. PugNAc incubation produced a time-dependent increase in vascular phosphorylation of myosin light chain and decreased phosphorylation levels of AMP-activated protein kinase, which decreased the affinity of MLCK for Ca2+/calmodulin. Our data suggest that proteins that play an important role in the regulation of MLCK and MLCP activity are directly affected by O-GlcNAcylation, favoring vascular contraction.


Assuntos
Animais , Masculino , Músculo Liso Vascular/fisiologia , Cadeias Leves de Miosina/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Vasoconstrição/fisiologia , Aorta Torácica , Acetilglucosamina/análogos & derivados , Acetilglucosamina/farmacologia , Acilação/efeitos dos fármacos , Acilação/fisiologia , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Azepinas/farmacologia , Western Blotting , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Quinase de Cadeia Leve de Miosina/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Oxazóis/farmacologia , Oximas/farmacologia , Fenilcarbamatos/farmacologia , Fenilefrina/agonistas , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Ratos Wistar , Ribonucleotídeos/farmacologia , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores
14.
Braz. j. med. biol. res ; 47(9): 789-798, 09/2014. graf
Artigo em Inglês | LILACS | ID: lil-719317

RESUMO

We examined the contractile responsiveness of rat thoracic aortas under pressure overload after long-term suprarenal abdominal aortic coarctation (lt-Srac). Endothelium-dependent angiotensin II (ANG II) type 2 receptor (AT2R)-mediated depression of contractions to ANG II has been reported in short-term (1 week) pressure-overloaded rat aortas. Contractility was evaluated in the aortic rings of rats subjected to lt-Srac or sham surgery (Sham) for 8 weeks. ANG I and II levels and AT2R protein expression in the aortas of lt-Srac and Sham rats were also evaluated. lt-Srac attenuated the contractions of ANG II and phenylephrine in the aortas in an endothelium-independent manner. However, lt-Srac did not influence the transient contractions induced in endothelium-denuded aortic rings by ANG II, phenylephrine, or caffeine in Ca2+-free medium or the subsequent tonic constrictions induced by the addition of Ca2+ in the absence of agonists. Thus, the contractions induced by Ca2+ release from intracellular stores and Ca2+ influx through stored-operated channels were not inhibited in the aortas of lt-Srac rats. Potassium-elicited contractions in endothelium-denuded aortic rings of lt-Srac rats remained unaltered compared with control tissues. Consequently, the contractile depression observed in aortic tissues of lt-Srac rats cannot be explained by direct inhibition of voltage-operated Ca2+ channels. Interestingly, 12-O-tetradecanoylphorbol-13-acetate-induced contractions in endothelium-denuded aortic rings of lt-Srac rats were depressed in the presence but not in the absence of extracellular Ca2+. Neither levels of angiotensins nor of AT2R were modified in the aortas after lt-Srac. The results suggest that, in rat thoracic aortas, lt-Srac selectively inhibited protein kinase C-mediated activation of contraction that is dependent on extracellular Ca2+ entry.


Assuntos
Animais , Masculino , Aorta Torácica/fisiopatologia , Coartação Aórtica/fisiopatologia , Cálcio/metabolismo , Endotélio Vascular/fisiologia , Músculo Liso Vascular/fisiopatologia , Proteína Quinase C/antagonistas & inibidores , Vasoconstrição/fisiologia , Angiotensina I/análise , Angiotensina II/análise , Aorta Torácica/lesões , Aorta Torácica/cirurgia , Western Blotting , Pressão Sanguínea/fisiologia , Cromatografia Líquida de Alta Pressão , Endotélio Vascular/lesões , Músculo Liso Vascular/metabolismo , Fármacos Neuromusculares Despolarizantes/farmacologia , Fenilefrina/farmacologia , Potássio/farmacologia , Proteína Quinase C/metabolismo , Radioimunoensaio , Ratos Wistar , /metabolismo , Vasoconstrição/efeitos dos fármacos
15.
Braz. j. med. biol. res ; 47(5): 411-418, 02/05/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-709437

RESUMO

Transcutaneous electrical nerve stimulation (TENS) is a type of therapy used primarily for analgesia, but also presents changes in the cardiovascular system responses; its effects are dependent upon application parameters. Alterations to the cardiovascular system suggest that TENS may modify venous vascular response. The objective of this study was to evaluate the effects of TENS at different frequencies (10 and 100 Hz) on venous vascular reactivity in healthy subjects. Twenty-nine healthy male volunteers were randomized into three groups: placebo (n=10), low-frequency TENS (10 Hz, n=9) and high-frequency TENS (100 Hz, n=10). TENS was applied for 30 min in the nervous plexus trajectory from the superior member (from cervical to dorsal region of the fist) at low (10 Hz/200 μs) and high frequency (100 Hz/200 μs) with its intensity adjusted below the motor threshold and intensified every 5 min, intending to avoid accommodation. Venous vascular reactivity in response to phenylephrine, acetylcholine (endothelium-dependent) and sodium nitroprusside (endothelium-independent) was assessed by the dorsal hand vein technique. The phenylephrine effective dose to achieve 70% vasoconstriction was reduced 53% (P<0.01) using low-frequency TENS (10 Hz), while in high-frequency stimulation (100 Hz), a 47% increased dose was needed (P<0.01). The endothelium-dependent (acetylcholine) and independent (sodium nitroprusside) responses were not modified by TENS, which modifies venous responsiveness, and increases the low-frequency sensitivity of α1-adrenergic receptors and shows high-frequency opposite effects. These changes represent an important vascular effect caused by TENS with implications for hemodynamics, inflammation and analgesia.


Assuntos
Adulto , Humanos , Masculino , Acetilcolina/farmacologia , Fármacos Cardiovasculares/farmacologia , Mãos/irrigação sanguínea , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Estimulação Elétrica Nervosa Transcutânea/métodos , Análise de Variância , Glicemia , Colesterol/sangue , Contagem de Eritrócitos , Contagem de Leucócitos , Lipoproteínas HDL/sangue , Triglicerídeos/sangue , Ureia/sangue , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Veias/efeitos dos fármacos
16.
Clinics ; 68(12): 1537-1542, dez. 2013. graf
Artigo em Inglês | LILACS | ID: lil-697707

RESUMO

OBJECTIVES: Estrogen has been shown to play an important protective role in non-reproductive systems, such as the cardiovascular system. Our aim was to observe gender differences in vivo with regard to the increase in macromolecular permeability and leukocyte-endothelium interaction induced by ischemia/reperfusion as well as in microvascular reactivity to vasoactive substances using the hamster cheek pouch preparation. METHODS: Thirty-six male and 36 female hamsters, 21 weeks old, were selected for this study, and their cheek pouches were prepared for intravital microscopy. An increase in the macromolecular permeability of post-capillary venules was quantified as a leakage of intravenously injected fluorescein-labeled dextran, and the leukocyte-endothelium interaction was measured as the number of fluorescent rolling leukocytes or leukocytes adherent to the venular wall, labeled with rhodamin G, during reperfusion after 30 min of local ischemia. For microvascular reactivity, the mean internal diameter of arterioles was evaluated after the topical application of different concentrations of two vasoconstrictors, phenylephrine (α1-agonist) and endothelin-1, and two vasodilators, acetylcholine (endothelial-dependent) and sodium nitroprusside (endothelial-independent). RESULTS: The increase in macromolecular permeability induced by ischemia/reperfusion was significantly lower in females compared with males [19 (17-22) leaks/cm2 vs. 124 (123-128) leaks/cm2, respectively, p<0.001), but the number of rolling or adherent leukocytes was not different between the groups. Phenylephrine-induced arteriolar constriction was significantly lower in females compared with males [77 (73-102)% vs. 64 (55-69)%, p<0.04], but there were no detectable differences in endothelin-1-dependent vasoreactivity. Additionally, arteriolar vasodilatation elicited by acetylcholine or sodium nitroprusside did not differ between the groups. CONCLUSION: The ...


Assuntos
Animais , Cricetinae , Feminino , Masculino , Sistema Cardiovascular/metabolismo , Estrogênios/metabolismo , Microcirculação/fisiologia , Acetilcolina/farmacologia , Permeabilidade Capilar , Adesão Celular/fisiologia , Bochecha/irrigação sanguínea , Endotélio Vascular/fisiologia , Leucócitos/fisiologia , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Traumatismo por Reperfusão/metabolismo , Fatores Sexuais , Fatores de Tempo
17.
Arq. bras. cardiol ; 100(4): 339-346, abr. 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-674192

RESUMO

FUNDAMENTO: A hipertensão arterial é uma síndrome multifatorial, crônica, causada tanto por fatores congênitos ou adquiridos. OBJETIVO: Avaliar os efeitos do treinamento físico resistido (TR) sobre pressão arterial, reatividade e morfologia vascular de ratos hipertensos induzidos por L-NAME. MÉTODOS: Ratos Wistar machos (200-250 g) foram divididos em 3 grupos: normotenso sedentário (NS), hipertenso sedentário (HS) e hipertenso treinado (HT). A hipertensão foi induzida pela administração de L-NAME (40 mg/kg) na água de beber por 4 semanas. A pressão arterial foi avaliada antes e após o TR. O TR foi realizado utilizando 50% de 1RM, em 3 séries de 10 repetições, 3 vezes por semana, durante quatro semanas. A reatividade vascular foi mensurada em artéria mesentérica superior por curvas concentração resposta ao nitroprussiato de sódio (NPS) e fenilefrina (FEN). Além disso, foram realizadas análises histológicas e estereológicas. RESULTADOS: O TR inibiu o aumento das pressões arteriais média e diastólica. Foi observada uma redução significativa na resposta máxima e na potência da FEN entre os grupos HS e HT. A análise histológica evidenciou aspecto normal para as túnicas íntima, média e adventícia em todos os grupos. Não houve diferença significativa nas áreas do lúmen, da túnica média e total das artérias dos grupos HS e HT em relação ao NS. A razão parede/lúmen arterial do grupo HS apresentou diferença significativa em relação ao NS (p < 0,05), mas esta não foi diferente do HT. CONCLUSÕES: O TR foi capaz de prevenir a elevação da pressão arterial sob as condições deste estudo. Este controle parece envolver a regulação de mecanismo vasoconstritor e a manutenção do diâmetro luminal de ratos hipertensos induzidos por L-NAME.


BACKGROUND: Arterial hypertension is a multifactorial chronic condition caused by either congenital or acquired factors. OBJECTIVE: To evaluate the effects of Resistance Training (RT) on arterial pressure, and on vascular reactivity and morphology, of L-NAME-treated hypertensive rats. METHODS: Male Wistar rats (200 - 250 g) were allocated into Sedentary Normotensive (SN), Sedentary Hypertensive (SH) and Trained Hypertensive (TH) groups. Hypertension was induced by adding L-NAME (40 mg/Kg) to the drinking water for four weeks. Arterial pressure was evaluated before and after RT. RT was performed using 50% of 1RM, 3 sets of 10 repetitions, 3 times per week for four weeks. Vascular reactivity was measured in rat mesenteric artery rings by concentration-response curves to sodium nitroprusside (SNP); phenylephrine (PHE) was also used for histological and stereological analysis. RESULTS: Resistance training inhibited the increase in mean and diastolic arterial pressures. Significant reduction was observed in Rmax (maximal response) and pD2 (potency) of PHE between SH and TH groups. Arteries demonstrated normal intima, media and adventitia layers in all groups. Stereological analysis demonstrated no significant difference in luminal, tunica media, and total areas of arteries in the SH and TH groups when compared to the SN group. Wall-to-lumen ratio of SH arteries was significantly different compared to SN arteries (p<0.05) but there was no difference when compared to TH arteries. CONCLUSIONS: RT was able to prevent an increase in blood pressure under the conditions in this study. This appears to involve a vasoconstrictor regulation mechanism and maintenance of luminal diameter in L-NAME induced hypertensive rats.


Assuntos
Animais , Masculino , Ratos , Pressão Sanguínea/fisiologia , Hipertensão/metabolismo , Condicionamento Físico Animal/métodos , Treinamento de Resistência , Vasoconstrição/fisiologia , Análise de Variância , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Hipertensão/induzido quimicamente , Hipertensão/patologia , Artéria Mesentérica Superior/fisiologia , NG-Nitroarginina Metil Éster , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Distribuição Aleatória , Ratos Wistar , Vasoconstritores/farmacologia , Vasodilatadores/farmacologia
18.
Arq. bras. cardiol ; 100(2): 180-186, fev. 2013. tab
Artigo em Português | LILACS | ID: lil-667960

RESUMO

FUNDAMENTO: Diversos mecanismos podem estar envolvidos no desencadeamento da síncope em pacientes com cardiomiopatia hipertrófica (CMH), incluindo colapsos hemodinâmicos que podem estar relacionados a um desequilíbrio autonômico. OBJETIVO: Avaliar e comparar a função autonômica de pacientes que apresentam CMH com síncope inexplicada (SI) com os que não apresentam síncope. MÉTODOS: Trinta e sete pacientes foram incluídos, sendo 16 com SI e 21 sem síncope. Sua função autonômica foi avaliada por sensibilidade barorreflexa (SB) espontânea e induzida por fenilefrina, pela variabilidade da frequência cardíaca (VFC) no domínio do tempo durante o Holter de 24 horas e no domínio da frequência (análise espectral), ambos em decúbito dorsal e no teste de inclinação (TI) a 70º. RESULTADOS: A SB espontânea mostrou-se semelhante em ambos os grupos (16,46 ± 12,99 vs. 18,31 ± 9,88 ms/mmHg, p = 0,464), assim como a SB induzida por fenilefrina (18,33 ± 9,31 vs. 15,83 ± 15,48 ms/mmHg, p = 0,521). Não foram observadas diferenças no SDNN (137,69 ± 36,62 vs . 145,95 ± 38,07 ms, p = 0,389). O grupo com síncope apresentou um RMSSD significativamente menor (24,88 ± 10,03 vs. 35,58 ± 16,43 ms, p = 0,042) e tendência a menor pNN50 (4,51 ± 3,78 vs . 8,83 ± 7,98%, p =0,085) e a menores valores do componente de alta frequência da análise espectral da VFC em repouso (637,59 ± 1.295,53 vs. 782,65 ± 1.264,14 ms2 , p = 0,075). Nenhuma diferença significativa foi observada em resposta ao TI (p = 0,053). A sensibilidade, especificidade e acurácia do TI na identificação da etiologia da SI em pacientes com CMH foram 6%, 66% e 40%, respectivamente. CONCLUSÃO: Observou-se tônus parassimpático mais baixo em pacientes com CMH e SI, mas a relevância clínica deste achado ainda não está clara. O TI não é uma ferramenta vantajosa para avaliar a origem da síncope em tais doentes, principalmente por causa da sua baixa especificidade.


BACKGROUND: Several mechanisms may be involved in the trigger of syncope in patients with hypertrophic cardiomyopathy (HCM), including hemodynamic collapses that might be related to an autonomic imbalance. OBJECTIVE: To evaluate and compare the autonomic function of patients presenting HCM with unexplained syncope (US) to those without syncope. METHODS: Thirty-seven patients were included, 16 with US and 21 without syncope. Their autonomic function was assessed by spontaneous and phenylephrine induced baroreflex sensitivity (BRS), by heart rate variability (HRV) in time domain during 24-hour Holter and in frequency domain (spectral analysis), both in supine position and at 70º head-up tilt (HUT). RESULTS: The spontaneous BRS was similar in both groups (16,46 ± 12,99 vs. 18,31 ± 9,88 ms/mmHg, p = 0,464), as was phenylephrine-induced BRS (18,33 ± 9,31 vs. 15,83 ± 15,48 ms/mmHg, p = 0,521). No differences were observed in SDNN (137,69 ± 36,62 vs . 145,95 ± 38,07 ms, p=0,389). The group presenting syncope had a significantly lower RMSSD (24,88±10,03 vs. 35,58 ± 16,43 ms, p = 0,042) and a tendency to lower pNN50 (4,51 ± 3,78 vs . 8,83 ± 7,98%, p =0,085) and lower values of the high frequency component of HRV spectral analysis at rest (637,59±1.295,53 vs. 782,65±1.264,14ms2, p=0,075). No significant difference was observed in response to HUT (p = 0,053). HUT sensitivity, specificity and accuracy in identifying the etiology of US in HCM patients were 6%, 66% and 40%, respectively. CONCLUSIONS: A lower parasympathetic tone was observed in HCM patients with US, but the clinical relevance of this finding remains unclear. HUT is not a valuable tool for evaluating the origin of syncope in these patients, mainly because of its poor specificity.


Assuntos
Adulto , Feminino , Humanos , Masculino , Sistema Nervoso Autônomo/fisiopatologia , Barorreflexo/fisiologia , Cardiomiopatia Hipertrófica/fisiopatologia , Frequência Cardíaca/fisiologia , Síncope/fisiopatologia , Barorreflexo/efeitos dos fármacos , Métodos Epidemiológicos , Fenilefrina/administração & dosagem , Decúbito Dorsal/fisiologia , Teste da Mesa Inclinada
19.
Arq. bras. cardiol ; 98(1): 29-34, jan. 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-613421

RESUMO

FUNDAMENTO: A doença coronária tem sido amplamente estudada em pesquisas cardiovasculares. No entanto, pacientes com doença arterial periférica (DAP) têm piores resultados em comparação àqueles com doença arterial coronariana. Portanto, os estudos farmacológicos com artéria femoral são altamente relevantes para a melhor compreensão das respostas clínicas e fisiopatológicas da DAP. OBJETIVO: Avaliar as propriedades farmacológicas dos agentes contráteis e relaxantes na artéria femoral de ratos. MÉTODOS: As curvas de resposta de concentração à fenilefrina contrátil (FC) e à serotonina (5-HT) e os agentes relaxantes isoproterenol (ISO) e forskolina foram obtidos na artéria femoral de ratos isolada. Para as respostas ao relaxamento, os tecidos foram contraídos com FC ou 5-HT. RESULTADOS: A potência de classificação na artéria femoral foi de 5-HT > FC para as respostas contráteis. Em tecidos contraídos com 5-HT, as respostas de relaxamento ao isoproterenol foram praticamente abolidas em comparação aos tecidos contraídos com FC. A forskolina, um estimulante da adenilil ciclase, restaurou parcialmente a resposta de relaxamento ao ISO em tecidos contraídos com 5-HT. CONCLUSÃO: Ocorre uma interação entre as vias de sinalização dos receptores β-adrenérgicos e serotoninérgicos na artéria femoral. Além disso, esta pesquisa fornece um novo modelo para estudar as vias de sinalização serotoninérgicas em condições normais e patológicas que podem ajudar a compreender os resultados clínicos na DAP.


BACKGROUND: Coronary heart disease has been widely studied in cardiovascular research. However, patients with peripheral artery disease (PAD) have worst outcomes compared to those with coronary artery disease. Therefore, pharmacological studies using femoral artery are highly relevant for a better understanding of the pathophysiologic responses of the PAD. OBJECTIVE: The aim of this study was to evaluate the pharmacologic properties of the contractile and relaxing agents in rat femoral artery. METHODS: Concentration response curves to the contractile phenylephrine (PE) and serotonin (5-HT) and the relaxing agents isoproterenol (ISO) and forskolin were obtained in isolated rat femoral artery. For relaxing responses, tissues were precontracted with PE or 5-HT. RESULTS: The order rank potency in femoral artery was 5-HT > PE for contractile responses. In tissues precontracted with 5-HT, relaxing responses to isoproterenol was virtually abolished as compared to PE-contracted tissues. Forskolin, a stimulant of adenylyl cyclase, partially restored the relaxing response to ISO in 5-HT-precontracted tissues. CONCLUSION: An interaction between β-adrenergic- and serotoninergic- receptors signaling pathway occurs in femoral artery. Moreover, this study provides a new model to study serotoninergic signaling pathway under normal and pathological conditions which can help understanding clinical outcomes in the PAD.


FUNDAMENTO: La enfermedad coronaria ha sido ampliamente estudiada en las investigaciones cardiovasculares. Sin embargo, los pacientes con enfermedad arterial periférica (EAP), tienen los peores resultados en comparación con aquellos con la enfermedad arterial coronaria. Por tanto, los estudios farmacológicos con la arteria femoral son extremadamente importantes para obtener una mejor comprensión de las respuestas clínicas y fisiopatológicas de la EAP. OBJETIVO: Evaluar las propiedades farmacológicas de los agentes contráctiles y relajantes en la arteria femoral de los ratones. MÉTODOS: Las curvas de concentración-respuesta a los agentes conctráctiles fenilefrina (FE) y a la serotonina (5-HT) y los agentes relajantes isoproterenol (ISO) y forskolina, se obtuvieron en la arteria femoral de ratones ya aislada. Para las respuestas a la relajación, los tejidos fueron contraídos con FE o 5-HT. RESULTADOS: La potencia de clasificación en la arteria femoral fue de 5-HT > FE para las respuestas contráctiles. En los tejidos contraídos con 5-HT, las respuestas de relajación al isoproterenol fueron prácticamente eliminadas en comparación con los tejidos contraídos con FE. La forskolina, un estimulante de la adenilil ciclasa, restauró parcialmente la respuesta de relajación al ISO en los tejidos contraídos con 5-HT. CONCLUSIÓN: Ocurre una interacción entre las vías de señalización de los receptores β-adrenérgicos y serotoninérgicos en la arteria femoral. Además, esa investigación suministra un nuevo modelo para estudiar las vías de señalización serotoninérgicas en condiciones normales y patológicas que puedan ayudar a comprender los resultados clínicos en la EAP.


Assuntos
Animais , Masculino , Ratos , Artéria Femoral/efeitos dos fármacos , Doença Arterial Periférica/fisiopatologia , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatadores/farmacologia , Colforsina/farmacologia , Isoproterenol/farmacologia , Modelos Animais , Fenilefrina/farmacologia , Ratos Wistar , Serotonina/farmacologia
20.
Bol. latinoam. Caribe plantas med. aromát ; 10(5): 414-422, sept. 2011. tab, graf
Artigo em Inglês | LILACS | ID: lil-618822

RESUMO

Ruta chalepensis, is used, in traditional medicine, as emmenagogue, abortive, and analgesic. We analyzed, in male Wistar rats, the effects of the chronic intake of an infusion of Ruta chalepensis (20 g/L) on the vasomotor responses of, either intact or endothelium-denuded aortic rings, to phenylephrine or carbachol. Only in rings with endothelium significant effects were observed. The infusion induced a leftward shift of the concentration-response curve to phenylephrine and an increase in maximal tension development. These effects were abolished by indomethacin. In these rings, inhibiting the synthesis of nitric oxide, in the presence of indomethacin, induced a leftward shift of the concentration response curve to phenylephrine, as well as an increase in maximal tension. These results suggest that the chronic ingestion of a Ruta chalepensis infusion induces an endothelium dependent increase in the synthesis/release of cyclooxygenase-dependent vasoconstrictor prostanoids, and an increase in the basal synthesis/release of nitric oxide.


Ruta chalepensis se utiliza en la medicina tradicional como emenagogo, abortivo y analgésico. Se analizaron, en ratas Wistar macho, los efectos de la ingesta crónica de una infusión de Ruta chalepensis (20 g /L), sobre las respuestas vasomotoras de anillos de aorta con y sin endotelio, a la fenilefrina o al carbacol Se observaron efectos significativos sólo en anillos con endotelio. La infusión indujo un desplazamiento a la izquierda de la curva de concentración-respuesta a fenilefrina y un incremento en la tensión máxima desarrollada. Estos efectos fueron abolidos por la indometacina. La inhibición de la síntesis de óxido nítrico, en presencia de indometacina, produjo un desplazamiento a la izquierda de la curva de concentración-respuesta a la fenilefrina, así como un incremento en la tensión máxima. Estos resultados sugieren que la ingesta crónica de una infusión de Ruta chalepensis induce un incremento en la síntesis/liberación de prostanoides vasoconstrictores dependientes de la ciclooxigenasa y un aumento en la síntesis /liberación basal de óxido nítrico.


Assuntos
Masculino , Animais , Ratos , Aorta , Endotélio Vascular , Extratos Vegetais/administração & dosagem , Ruta/química , Carbacol/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Extratos Vegetais/farmacologia , Fenilefrina/farmacologia , Óxido Nítrico , Ratos Wistar
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