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El objetivo de la presente investigación fue determinar la influencia de la administración de óxido nitroso sobre la capacidad constrictora de la noradrenalina sobre el músculo liso vascular aórtico, en ratas con estrés oxidativo desencadenado por la hiperglucemia en un modelo experimental de diabetes mellitus inducida con estreptozotocina promoviendo en consecuencia disfunción endotelial. Se evaluaron la glucemia, el indicador de estrés oxidativo malondialdehído (MDA) y la respuesta vasorreactiva de anillos aislados de aorta torácica. El estudio se realizó con los anillos aórticos aislados de 20 ratas de especie Rattus norvegicus variación albinus línea Sprague-Dawley, que se dividieron aleatoriamente en cuatro grupos (n=5 cada uno): Blanco, sin inducción de hiperglucemia se obtuvieron los valores referenciales (normales) de vasocontracción y vasorrelajación; Control, con hiperglucemia se obtuvieron las respuestas vasoactivas disfuncionantes; Experimental 1, con hiperglucemia más óxido nitroso se indujo la vasocontracción con noradrenalina; Experimental 2, con hiperglucemia más óxido nitroso se indujo la vasocontracción con fenilefrina. Para el estudio experimental con enfoque cuantitativo, se indujo la contracción vascular con 3 dosis crecientes de noradrenalina (0,1, 1,0 y 10,0 μM) mientras que, la respuesta vasorrelajante se realizó con 4 dosis crecientes de acetilcolina (0,01, 0,1, 1,0 y 10,0 μM). Para el análisis estadístico se calculó el estadístico F de Friedman y la prueba Post Hoc de Bonferroni de Kruskal-Wallis, considerando un nivel de significancia del 95%. Se observó un incremento significativo en la respuesta vasoconstrictora a la noradrenalina en el grupo Experimental 1 (116,14 %) en comparación con los grupos Blanco (100%) y Control (106,14) (p < 0,01). Lo que demostró que la incubación con óxido nitroso a la concentración de 300pp/millón fue el responsable de tal efecto. Resultado similar (significativo) se obtuvo con el grupo Experimental 2 (116,70%) donde se indujo la vasocontracción con fenilefrina demostrando con ello, que la influencia del óxido nitroso no solamente fue con sustratos adrenérgicos endógenos sino también con los simpático miméticos exógenos como la fenilefrina.En conclusión, el óxido nitroso actuaría tal vez estimulando a los receptores alfa adrenérgicos y en consecuencia incrementando la disfunción endotelial resultado del estrés oxidativo.

Introducción: el Camphenol Plus es un derivado clorofenólico empleado como medicación intraconducto durante los tratamientos pulporradiculares en Estomatología. Son escasos los reportes científicos sobre el papel de los canales de iones potasio en la dinámica contráctil del músculo liso arterial inducida por dicho medicamento. Objetivo: determinar el papel de los canales de iones potasio en la dinámica contráctil del músculo liso arterial inducida por Camphenol Plus. Método: se realizó una investigación experimental preclínica en el Instituto de Fisiología “Oscar Langerdorff”, Facultad de Medicina, Universidad de Rostock, Alemania, entre octubre y diciembre de 2018, con el empleo de 30 anillos de aorta obtenidos de 10 ratas Wistar (n=10). Las preparaciones biológicas se colocaron en baño de órganos y se preactivaron con solución Krebs concentrada en iones potasio, registrándose luego la tensión desarrollada por el músculo liso vascular tras la adición de soluciones de Camphenol Plus durante diferentes intervalos de tiempo. Se utilizaron las pruebas de Wilcoxon y U de Mann-Whitney. Resultados: el 31,4 % de la musculatura lisa vascular se relajó por acción del Camphenol Plus tras la preactivación con solución Krebs concentrada en iones potasio. El mayor descenso del tono vascular se produjo con el uso de soluciones del medicamento al 7 % entre el primer y tercer minutos. Conclusiones: el efecto vasorrelajante in vitro producido por Camphenol Plus sobre el músculo liso arterial está mediado por canales de iones potasio sensibles a voltaje, a calcio y a trifosfato de adenosina del endotelio vascular y el sarcolema.

Producción Científica, Objectives: Restenosis after vessel angioplasty due to dedifferentiation of the vascular smooth muscle cells (VSMCs) limits the success of surgical treatment of vascular occlusions. Type 2 diabetes (T2DM) has a major impact on restenosis, with patients exhibiting more aggressive forms of vascular disease and poorer outcomes after surgery. Kv1.3 channels are critical players in VSMC proliferation. Kv1.3 blockers inhibit VSMCs MEK/ERK signalling and prevent vessel restenosis. We hypothesize that dysregulation of microRNAs (miR) play critical roles in adverse remodelling, contributing to Kv1.3 blockers efficacy in T2DM VSMCs. Methods and results: We used clinically relevant in vivo models of vascular risk factors (VRF) and vessels and VSMCs from T2DM patients. Results: Human T2DM vessels showed increased remodelling, and changes persisted in culture, with augmented VSMCs migration and proliferation. Moreover, there were downregulation of PI3K/AKT/mTOR and upregulation of MEK/ERK pathways, with increased miR-126 expression. The inhibitory effects of Kv1.3 blockers on remodelling were significantly enhanced in T2DM VSMCs and in VRF model. Finally, miR-126 overexpression confered “diabetic” phenotype to non-T2DM VSMCs by downregulating PI3K/AKT axis. Conclusions: miR-126 plays crucial roles in T2DM VSMC metabolic memory through activation of MEK/ERK pathway, enhancing the efficacy of Kv1.3 blockers in the prevention of restenosis in T2DM patients., Ministerio de Economía, Industria y Competitividad (grant BFU2016-75360-R and SAF2016-77871-C2-1-R), Junta de Castilla y León (grants VA114P17; VA172P20 and CLU-2019-02), Novo Nordisk Foundation (grant 34366), Swedish Research Council (grants 2017–00860 and 2020-01145), Swedish Heart and Lung Foundation (grant 20200322)

Introducción: el p-clorofenol alcanforado es un derivado clorofenólico de uso común como medicación intraconducto en Endodoncia. Son escasos los reportes científicos sobre sus efectos en la musculatura lisa vascular arterial y la regulación del flujo sanguíneo local. Objetivo: determinar el efecto del p-clorofenol alcanforado sobre la dinámica contráctil del músculo liso vascular arterial en el tiempo. Método: se realizó una investigación experimental preclínica utilizando 14 anillos de aorta obtenidos de ratas Wistar. Los anillos se colocaron en baño de órganos y se preactivaron con noradrenalina, registrándose luego la tensión desarrollada por el músculo liso vascular tras la adición de p-clorofenol alcanforado durante diferentes intervalos de tiempo. Resultados: el 51,4 % de la musculatura lisa vascular se relajó por la acción del p-clorofenol alcanforado. El mayor descenso del tono vascular se produjo entre el tercer y quinto minuto de añadido el medicamento. Las pruebas de Wilcoxon de los rangos con signos evidenciaron diferencias significativas entre la tensión base inicial y la registrada en los diferentes intervalos de tiempo estudiados. Conclusiones: el p-clorofenol alcanforado, induce in vitro, relajación del músculo liso arterial a través de un acoplamiento excitación-contracción de tipo farmacomecánico, la cual se incrementa en función del tiempo.

Orientador: Paulo Cesar Rodrigues Palma Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas Resumo: Os agentes antimuscarínicos permanecem como drogas de primeira linha para o tratamento da Síndrome da Bexiga Hiperativa (SBH), a despeito das dúvidas ainda existentes sobre a significância clínica e sua eficácia. Poucos fármacos que atuam por meio de mecanismos distintos dos antimuscarínicos, têm demonstrado eficácia no tratamento da SBH. Ravonóides são um grupo de compostos polifenólicos que têm recebido especial atenção dentro da pesquisa básica e clínica devido ao seu amplo espectro de atividade farmacológica. Recentemente, um estudo in vitro demonstrou que o fIavonóide galangina exerce uma atividade inibitória sobre a contratilidade da bexiga de ratos. Esta tese foi desenvolvida a fim de examinar os efeitos da galangina sobre a resposta contrátil da bexiga de suínos e testar a hipótese de um efeito sobre a mobilização do cálcio. Além disso, investigou-se a eficácia da galangina em promover uma ação protetora sobre o dano da musculatura lisa da bexiga causada por um período de estimulação elétrica repetitiva, o qual é empregado como um modelo, in vitro, de hiperrefIexia. Em um grupo de experimentos, fragmentos do detrusor de suínos foram submetidos a um período de 90 mÍn de estimulação elétrica de repetição. Galangina, em diferentes concentrações, foi adicionada ao banho do órgão a fim de determinar seu possível efeito protetor durante a estimulação elétrica. Em outro grupo de experimentos, a resposta contrátil ao carbacol, cafeína, potássio e eletroestímulo foi determinada antes e após a adição de galangina (3xl0-sM) ao meio. Os efeitos do fIavonóide foram também avaliados após a administração de diferentes antagonistas no banho de órgão. Galangina (1O-7M) evitou o decréscimo da resposta contrátil do músculo liso causada por um período de estimulação elétrica de repetição. vesical Galangina inibiu a amplitude da contração detrusora induzi da pelo eletro-estímulo, carbacol, cafeína e potássio (p0,05). Entretanto, quando verapamil foi adicionado ao meio de estudo, a inibição da contração foi parcialmente abolida. Concluindo, os experimentos acima descritos demonstraram que a galangina, em concentração nanomolar, exerceu um efeito protetor sobre a musculatura detrusora. Entretanto, quando empregado em uma concentração micromolar, o flavonóide promoveu einibição da musculatura lisa vesical, o qual resultou de uma ação sobre a mobilização do cálcio extra e intracelular Abstract: Antimuscarinjc agents remain first-line therapy for the overactive bladder syndrome (OAB), despite doubts about the clinjcal signifjcance of their effectiveness. Few drugs acting through other mechanisms have been found to be efficacious for treatment of GAB. Flavonoids are a group of polyphenolic compounds and have recently gained tremendous interest, due to their broad pharmacologjcal activity. Recently, the inhibitory effect of galangin, a member of the flavonol class of flavonoid, on rat bladder contractility has been investigated. This thesis was undertaken to further examine the actions of galangin on the contractile responses of bladder strips and to test the hypothesis that an effect on calcium mobilization in smooth muscle cells is involved. Furthermore, it was investigated the efficacy of galangin to counteract the detrusor damage caused by the smooth muscle of the urinary bladder being exposed to repetitive field stimulation (RFS), as a model of hyperreflexia. In one experiment, pig detrusor strips were mounted for tension recording in organ baths and were subjected to RFS for 90min. Galangin, at different concentrations, was added to the organ bath in order to determine its protective effect on RFS. In another experiment the contractile response to carbachol, potassium and electrical field stimulation - EFS were determined before and after the addition of galangin (3xlO-sM). Furthermore, the effect of galangin was also evaluated after the administration in the bath of a number of antagonists. Galangin (1O-7M)avoided the decrease in contractile smooth muscle response of strips to EFS during RFS. Galangin inhibited the maximal contractile response to EFS, carbachol, caffeine media and potassium (pO,O5).However, when verapamil was added to the medium, the inhibitory effects of galangin were partially blocked. In summary, the current experiments have shown that galangin, in subllmol concentrations, exerted a protective effect on bladder smooth muscle contractility. Furthermore, galangin, in !lIDO!concentrations inhibited pig bladder contractility, which probably resulted from an action on Ca2+mobilization from intracellu!ar stores as well as influx of calcium. At the present, there is no proof that our results are reproducible in functional or dysfunctional human bladders. Further study is needed to investigate the potential of ga!anginto be used to inhibited overactive bladder syndrome in vivo Doutorado Cirurgia Doutor em Cirurgia

Previous results showed the ethyl acetate phase (SP-AcOEt), obtained from aerial parts of Solanum paludosum, relaxed the aorta isolated in the endothelium-dependent and -independent manner. The vasorelaxant effects of SP-AcOEt was not characterized on aorta rings endothelium-denuded, thus this work aimed to elucidate the mechanisms endothelium-independent vasorelaxation on rat isolated aorta. The aorta was isolated from Wistar rats and mounted in glass baths containing 6 mL of normal Krebs physiological solution with pH at 7.4. The preparation was maintained at 37ºC and bubbled continuously with a mixture of 95% O2 and 5% CO2. Aortic rings were maintained for 1 hour by a resting tension of 1g and next were contracted with phenylephrine after the sustained contraction ACh was added to access the integrity of the endothelium. SP-AcOEt relaxed pre-contracted aorta by KCl-30mM or -80mM in a similar manner, suggesting blockade CaV, but not channel-K+ participating. SP-AcOEt also inhibited the contraction induced by CaCl2 and relaxed pre-contracted aorta by (±)-BayK8644 (EC50 = 16.9±1.3 μg/mL), which confirms the involvement of L-type CaV blockade. SP-AcOEt presented vasorelaxation endothelium-independent that involves L-type CaV blockade. Resultados anteriores demostraron que la fase de acetato de etilo (SP-AcOEt), obtenida de las partes aéreas de Solanum paludosum, relajó la aorta aislada de forma dependiente e independiente del endotelio. Los efectos vasorrelajantes de SP-AcOEt no se caracterizaron en anillos aórticos sin endotelio, por lo que este trabajo tuvo como objetivo dilucidar los mecanismos de vasorrelajación independientes del endotelio en aorta aislada de rata. Las aortas se aislaron de ratas Wistar y se montaron en viales de vidrio para un órgano aislado que contenía 6 ml de solución salina de Krebs con pH 7,4. La preparación se mantuvo a 37ºC y se aireó continuamente con carbogen. Los anillos aórticos se mantuvieron estabilizados durante 1 h, bajo una tensión de reposo de 1 gy luego se precontrataron con Fen seguido de ACh, después de una contracción sostenida, para observar la integridad del endotelio funcional. La fase SP-AcOEt relajó la aorta precontraída con KCl-30 y KCl-80 mM de manera similar, lo que sugiere bloqueo de CaV, pero no la participación de canales de K+. SP-AcOEt también inhibió las contracciones inducidas por CaCl2, medio K+ y sin calcio, y relajó la aorta precontraída con (±)-BayK8644 (EC50 = 16,9±1,3 μg/mL), confirmando la afectación del bloqueo CaV tipo L. La fase SP-AcOEt mostró vasorrelajación independiente del endotelio que involucra bloqueo de CaV tipo L. Resultados anteriores mostraram que a fase acetato de etila (SP-AcOEt), obtida das partes aéreas de Solanum paludosum, relaxou a aorta isolada de maneira dependente e independente de endotélio. Os efeitos vasorrelaxantes de SP-AcOEt não foram caracterizados nos anéis de aorta sem endotélio, assim este trabalho objetivou elucidar os mecanismos vasorrelaxantes independentes de endotélio em aorta isolada de rato. As aortas foram isoladas de ratos Wistar e montadas em cubas de vidro para órgão isolado contendo 6 mL de solução fisiológica de Krebs com pH 7,4. A preparação era mantida a 37º C e aerada continuamente com carbogênio. Os anéis de aorta foram mantidos em estabilização por 1 h, sob tensão de repouso de 1 g, e depois foram pré-contraídos com fenilefrina seguido de ACh, após uma contração sustentada, para observar a integridade do endotélio funcional. A fase SP-AcOEt relaxou a aorta pré-contraída com KCl-30 e KCl-80mM de maneira similar, sugerindo o bloqueio de CaV, mas não a participação de canais-K+. SP-AcOEt também inibiu as contrações induzidas por CaCl2, meio alto K+ e sem cálcio, e relaxou a aorta pré-contraída com (±)-BayK8644 (CE50 = 16,9±1,3 μg/mL), confirmando o envolvimento do boqueio de CaV do tipo-L. A fase SP-AcOEt mostrou vasorrelaxamento independente de endotélio que envolve o bloqueio de CaV do tipo-L.

The rate of saphenous vein graft failure one year after coronary artery bypass grafting ranges from 10% to 25%. The aim of this study was to explore whether atorvastatin can reduce accumulation of vascular smooth muscle cells to inhibit intimal hyperplasia via p38 MAPK pathway inhibition.Forty-five Sprague-Dawley rats were randomized to three groups. Thirty rats received a vein graft operation, and they were randomized to be treated with vehicle or atorvastatin; fifteen rats received a sham operation. We detected intimal hyperplasia by hematoxylin-eosin staining and related protein expression by immunohistochemical and Western blot analysis. Comparisons were analyzed by single-factor analysis of variance and Fisher's least significant difference test, with p0.05 considered significant.The intima analyzed by hematoxylin-eosin staining was dramatically thicker in the control group than in the atorvastatin group and sham group (p0.01). The outcomes of immunohistochemical staining of α-SMA demonstrated that the percentage of α-SMA-positive cells in the control group was higher than in the atorvastatin group (p0.01). We also evaluated α-SMA, PCNA, p38 MAPK, and phosphorylation of p38 MAPK after statin treatment by Western blot analysis, and the results indicated that atorvastatin did not lead to p38 MAPK reduction (p0.05); it did, however, result in inhibition of p38 MAPK phosphorylation (p0.01), and it significantly reduced α-SMA and PCNA levels, in comparison with the control group (p0.01).We have demonstrated that atorvastatin can inhibit accumulation of vascular smooth muscle cells by inhibiting the p38 MAPK pathway, and it is capable of inhibiting intimal hyperplasia in a rat vein graft model.A taxa de falha de enxerto de veia safena um ano após a cirurgia de revascularização do miocárdio varia de 10% a 25%. O objetivo deste estudo foi de investigar se a atorvastatina pode reduzir o acúmulo de células musculares lisas vasculares para inibir a hiperplasia intimal por meio da inibição da via p38 MAPK.Quarenta e cinco ratos Sprague-Dawley foram randomizados em três grupos. Trinta ratos foram submetidos à cirurgia de enxerto de veia e randomizados para tratamento com veículo ou atorvastatina; quinze ratos foram submetidos à cirurgia sham. Detectamos a hiperplasia intimal por meio de coloração com hematoxilina-eosina e a expressão de proteínas relacionadas por meio de análise imuno-histoquímica e Western blot. Foram realizadas as comparações por análise de variância de fator único e pelo teste da diferença mínima significativa de Fisher, com p0,05 considerado significativo.A íntima analisada pela coloração com hematoxilina-eosina era dramaticamente mais espessa no grupo controle que no grupo atorvastatina e no grupo sham (p0,01). Os resultados da coloração imuno-histoquímica de α-SMA demonstraram que a porcentagem de células positivas para α-SMA no grupo controle era mais alta que no grupo atorvastatina (p0,01). Nós também avaliamos α-SMA, PCNA, p38 MAPK e fosforilação de p38 MAPK após o tratamento com estatina por meio de análise de Western blot e os resultados indicaram que a atorvastatina não levou à redução de p38 MAPK (p0,05); no entanto, resultou na inibição da fosforilação de p38 MAPK (p0,01) e reduziu significativamente os níveis de α-SMA e PCNA, em comparação com o grupo controle (p0,01).Nós demonstramos que a atorvastatina pode inibir o acúmulo de células musculares lisas vasculares por meio da inibição da via p38 MAPK e é capaz de inibir a hiperplasia intimal em modelos de enxerto de veia em ratos.

O-GlcNAcylation or O-GlcNAc modification is a post-translational modification of several proteins responsible for fundamental cellular processes. Dysregulation of the O-GlcNAc pathway has been linked to the etiology of several diseases such as neurodegenerative and cardiovascular diseases, type 2 diabetes and cancer. O-GlcNAcase (OGA) catalyzes the removal of O-GlcNAc from the modified proteins and several carbohydrate-based OGA inhibitors have been synthesized to understand the role of O-GlcNAc-modified proteins in physiological and pathological conditions. However, many of the inhibitors lack selectivity for OGA over lysosomal hexosaminidases A and B. Aiming the selectively inhibition of OGA, we propose herein the synthesis of twelve novel glucopyranoside derivatives exploring the bioisosteric replacement of the GlcNAc 2-acetamide group by 1,4-disubstituted 1,2,3-triazole ring, bearing a variety of central chains with different shapes. Compounds were readily prepared through "Copper(I) Catalyzed Azide/Alkyne Cycloaddition" (CuAAC) reaction between a sugar azide and different terminal alkynes. Initial Western Blot analyses and further inhibitory assays proved that compounds 6a (IC50 = 0.50 ± 0.02 μM, OGA), 6k (IC50 = 0.52 ± 0.01 μM, OGA) and 6l (IC50 = 0.72 ± 0.02 μM, OGA) were the most potent and selective compounds of the series. Structure-activity relationship analyses and molecular docking simulations demonstrated that the bridge of two-carbon atoms between the C-4 position of the triazole and the phenyl ring (6a), which may be replaced by heteroatoms such as N (6k) or O (6l), is fundamental for accommodation and inhibition within OGA catalytic pocket.

We hypothesized that SIRS/endotoxemia-associated hyporesponsiveness to vasoconstrictors is mediated by smaller increases in intracellular Ca(2+) levels due to reduced signaling via the STIM/Orai. Male Wistar rats were injected either with saline or bacterial LPS (i.p.; 10 mg/kg), and experiments were performed 24 h later. LPS-injected rats exhibited decreased systolic blood pressure, increased heart rate, neutrophils' migration into the peritoneal cavity, and elevated alanine aminotransferase levels. Additionally, second-order mesenteric arteries from endotoxemic rats displayed hyporeactivity to contractile agents such as phenylephrine and potassium chloride; decreased contractile responses to Ca(2+); reduced contraction during Ca(2+) loading; and smaller intracellular Ca(2+) stores. Decreased Orai1, but not STIM1, expression was found in resistance mesenteric arteries from LPS-treated rats. Additionally, cultured vascular smooth muscle cell (VSMC) treated with LPS resulted in increased TLR-4 expression, but Myd-88 and STIM-1 expression were not changed. Our data suggest that in endotoxemia, Ca(2+) homeostasis is disrupted in VSMC, with decreased Ca(2+) influx, smaller concentrations of Ca(2+) in the sarcoplasmic reticulum, and decreased activation of Orai1. Abnormal Ca(2+) handling contributes to LPS-associated vascular hyporeactivity.

Orientador: Prof Dr Ronaldo da Rocha Loures Bueno Coorientadores: Prof Gustavo Lenci Marques, Djanira Aparecida da Luz Veronez Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Medicina Interna. Defesa : Curitiba, 22/03/2018 Inclui referências: p.44-49 Resumo: Alterações relacionadas à idade envolvendo as células e a matriz extracelular da camada média da aorta estão ligadas a vários processos fisiológicos e patológicos observados no envelhecimento. Este estudo teve como objetivo avaliar e descrever quantitativamente as mudanças histológicas que ocorrem no processo de envelhecimento aórtico normal, mediante a mensuração da espessura da camada média da aorta torácica, número de células musculares lisas, e concentração de fibras colágenas e elásticas, em diferentes grupos etários, em um modelo experimental com ratos. Os animais do estudo (n=60) foram separados em cinco grupos de 12, alocados para diferentes tempos de vida (3, 6, 9, 18 e 24 meses), e ao final os animais passaram por eutanásia, sendo um segmento do primeiro centímetro da aorta descendente coletado e preparado para análise histológica com as colorações hematoxilina & eosina, tricrômico de Masson e Weigert. Imagens teciduais foram escaneadas, e campos aleatórios foram analisados por computador para medir a espessura da camada média, contar as células musculares lisas por campo, e quantificar as fibras elásticas e colágenas como proporção da área dos campos ocupadas por tais componentes. Como resultados: os grupos etários mais idosos demonstraram, espessura aumentada da camada média e contagem diminuída das células musculares lisas por campo, além de diminuição da proporção de fibras elásticas por campo. Tanto a redução da contagem de células musculares lisas quanto a da concentração de fibras elásticas tiveram significância estatística a partir do nono mês, e prosseguiram com o tempo. Notou-se uma tendência de aumento da proporção de fibras colágenas, sem atingir a significância estatística. Finalmente, com o envelhecimento, ocorre um aumento da matriz extracelular da camada média da aorta descendente, levando ao espessamento da mesma. Este espessamento deve-se ao conteúdo de colágeno, e esse processo resulta na diminuição da concentração de fibras elásticas e do número de células musculares lisas. Estas análises replicam achados de estudos prévios, de importantes implicações fisiológicas e patológicas em fenômenos vasculares e hemodinâmicos relacionados ao envelhecimento. Palavras-chave: envelhecimento, aorta torácica, camada média, espessura, músuclo liso vascular, fibras elásticas, colágeno vascular. Abstract: Age-related alterations involving aortic media layer's cells and extracellular matrix are linked to several physiological and pathological processes observed with aging. This study aimed to assess and quantitatively describe histological changes in normal aortic aging process through measurement of thoracic aorta's media layer thickness, media layer smooth muscle cell count, collagen and elastic fibers concentration, across different ages, in an experimental rat model. Study animals (n=60) were separated in five groups of 12, each ascribed a different lifetime (3, 6, 9, 18 and 24 months, respectively), at the completion of which animals underwent euthanasia and a segment of descending aorta's first centimeter was harvested and prepared for histological analysis with hematoxilin & eosin, Masson's trichrome and Weigert's stains. Tissue images were scanned and random fields underwent softwar analysis to measure media layer thickness, count smooth muscle cells per field and quantify elastic fibers and collagen, each of these expressed as the proportion of the fields' area occupied by these components. Results were as follows: older age groups exhibited, as compared to the younger, increased media layer thickness and decreased smooth muscle cell counts per field and decreased elastic fiber proportion per field. Both reductions on smooth muscle cell count and elastic fiber concentration were noted with statistical significance since month 9 and evolved thereafter. Collagen fibers showed a tendency to increase, without reaching statistical significance. In conclusion, with aging, descending aorta media layer extracellular matrix increases, leading to layer thickening. This increase is driven by the collagen content, and this process results in decreased elastic fiber concentration and smooth muscle cell count. These results have replicated findings from previous researches, and such findings have important physiologic and pathologic implications on age-related vascular and hemodynamic phenomena. Key-words: aging, thoracic aorta, media layer, thickness, vascular smooth muscle cells, elastic fibers, vascular collagen.

Atualmente, os antagonistas do receptor de mineralocorticóide (MR) pertencem ao arsenal terapêutico para o tratamento de diversas doenças cardiovasculares. No entanto, os mecanismos pelos quais essa classe de medicamentos exercem seus efeitos benéficos ainda não estão totalmente compreendidos. Evidências experimentais do nosso grupo têm demonstrado através de experimentos in vitro, ex vivo e in vivo que, parte dos efeitos deletérios da aldosterona, via ativação do MR, envolvem o aumento da expressão e atividade do Cav1.2, agindo como um importante gatilho para o desenvolvimento de patologias cardíacas. Portanto, o objetivo central deste estudo foi avaliar os mecanismos genômicos envolvidos na modulação da expressão do Cav1.2 pelo MR. The mineralocorticoid receptor (MR) antagonists belong to the current therapeutic armamentarium for the management of cardiovascular diseases, but the mechanisms conferring their beneficial effects are still poorly understood. Part of these MR effects might be related to the L-type Cav1.2 Ca2+ channel expression regulation, critically involved in heart failure and hypertension. Here, we show that MR acts as a transcription factor triggering aldosterone signal into specific alternative 'cardiac' P1-promoter usage, given rise to long (Cav1.2-LNT) N-terminal transcripts. Aldosterone increases Cav1.2- LNT expression in cardiomyocytes in a time- and dose-dependent manner due to MRdependent P1-promoter activity, through specific DNA sequence-MR interactions. This cis-regulatory mechanism induced a MR-dependent P1-promoter switch in vascular cells leading to a new Cav1.2-LNT molecular signature with reduced Ca2+ channel blocker sensitivity. These findings uncover Cav1.2-LNT as a specific mineralocorticoid target that might influence the therapeutic outcome of cardiovascular diseases. São Cristóvão, SE

Background: Resistance exercise (RE) has been recommended for patients with cardiovascular diseases. Recently, a few studies have demonstrated that the intensity of a single bout of RE has an effect on endothelial adaptations to exercise. However, there is no data about the effects of different volumes of RE on endothelium function. Objective: The aim of the study was to evaluate the effects of different volumes of RE in a single bout on endothelium-dependent vasodilatation and nitric oxide (NO) synthesis in the mesenteric artery of healthy animals. Methods: Male Wistar rats were divided into three groups: Control (Ct); low-volume RE (LV, 5 sets x 10 repetitions) and high-volume RE (HV, 15 sets x 10 repetitions). The established intensity was 70% of the maximal repetition test. After the exercise protocol, rings of mesenteric artery were used for assessment of vascular reactivity, and other mesenteric arteries were prepared for detection of measure NO production by DAF-FM fluorescence. Insulin responsiveness on NO synthesis was evaluated by stimulating the vascular rings with insulin (10 nM). Results: The maximal relaxation response to insulin increased in the HV group only as compared with the Ct group. Moreover, the inhibition of nitric oxide synthesis (L-NAME) completely abolished the insulin-induced vasorelaxation in exercised rats. NO production showed a volume-dependent increase in the endothelial and smooth muscle layer. In endothelial layer, only Ct and LV groups showed a significant increase in NO synthesis when compared to their respective group under basal condition. On the other hand, in smooth muscle layer, NO fluorescence increased in all groups when compared to their respective group under basal condition. Conclusions: Our results suggest that a single bout of RE promotes vascular endothelium changes in a volume-dependent manner. The 15 sets x 10 repetitions exercise plan induced the greatest levels of NO synthesis. Resumo Fundamentos: O exercício resistido (ER) tem sido recomendado para pacientes com doenças cardiovasculares. Recentemente, alguns estudos demonstraram que a intensidade de uma sessão de ER exerce um efeito sobre a disfunção endotelial. No entanto, não há dados sobre os efeitos de diferentes volumes de ER sobre a função endotelial. Objetivo: O objetivo deste estudo foi avaliar os efeitos de diferentes volumes de ER, realizados em uma única sessão, sobre a vasodilatação dependente do endotélio e síntese de óxido nítrico (NO) em artéria mesentérica de animais saudáveis. Métodos: Ratos Wistar machos foram divididos em três grupos: Controle (Ct); baixo volume (BV, 5 séries x 10 repetições) e alto volume de ER (AV, 15 séries x 10 repetições). Foi estabelecida a intensidade de 70% do teste de repetição máxima. Após o protocolo de exercício, anéis de artéria mesentérica foram utilizados na avaliação da reatividade vascular, e outras artérias mesentéricas foram preparadas para a detecção da produção de NO por fluorescência com para do DAF-FM. A resposta à insulina pela síntese de NO foi avaliada estimulando-se os anéis vasculares com insulina (10nM). Resultados: A resposta máxima do relaxamento induzido por insulina foi aumentada somente no grupo AV em comparação ao grupo Ct. Além disso, a inibição da síntese do NO (L-NAME), aboliu completamente o relaxamento vascular induzido por insulina em ratos exercitados. A produção de NO mostrou um aumento dependente do volume no endotélio e no músculo liso. No endotélio, apenas os grupos Ct e BV mostraram aumento significativo na síntese de NO quando comparado aos seus respectivos grupos sob condição basal. No entanto, no músculo liso, a fluorescência foi aumentada em todos os grupos quando comparados aos seus respectivos grupos sob a condição basal. Conclusões: Nossos resultados sugerem que uma única sessão de ER foi capaz de promover adaptações no endotélio vascular. Além disso, nós observamos que este efeito é volume-dependente e o volume de 15 séries x10 repetições induziu o maior aumento na síntese de NO.

Producción Científica, K+ channels encoded by the ether-a-go-go related gene (ERG1 or KCNH2) are important determinants of the cardiac action potential. Expression of both cardiac isoforms (ERG1a and ERG1b) were identified in murine portal vein and distinctive voltage-gated K+ currents were recorded from single myocytes. The aim of the present study was to ascertain the expression and functional impact of ERG channels in murine arteries., British Heart Foundation (projects PG/06/057/20864 and PG/11/93/21943), Medical Research Council (project MR/K019074/1), Ministerio de Economía, Industria y Competitividad (grants BFU2013-45867-R and BFU2016-75360)

Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified.To determine the effects of jabuticaba hydroalcoholic extract (JHE) on vascular smooth muscle (VSM) of isolated arteries.Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed.Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL). Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine) hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM).JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect.Embora a jabuticaba apresente importantes efeitos biológicos, suas ações sobre o sistema cardiovascular ainda não foram esclarecidas.Determinar os efeitos do extrato de jabuticaba (EHJ) sobre o músculo liso vascular (MLV) em artérias isoladas.Aortas (sem endotélio) de ratos foram montadas em banho de órgãos isolados para registro de tensão isométrica. Foram verificados o efeito relaxante, a influência dos canais de K+ e das fontes de Ca2+ intra- e extracelular sob a resposta estimulada pelo EHJ.Artérias pré-contraídas com fenilefrina apresentaram relaxamento concentração-dependente (0,380 a 1,92 mg/mL). O tratamento com bloqueadores de canais de K+ (tetraetilamônio, glibenclamida, 4-aminopiridina) prejudicaram o relaxamento pelo EHJ. A contração estimulada com fenilefrina também foi prejudicada pelo tratamento prévio com EHJ. A inibição da Ca2+ATPase do reticulo sarcoplasmático não alterou o relaxamento pelo EHJ. Além disso, o EHJ inibiu a contração causada pelo influxo de Ca2+ estimulado por fenilefrina e KCl (75 mM).O EHJ induz vasodilatação independente do endotélio. Ativação dos canais de K+ e inibição do influxo de Ca2+ através da membrana estão envolvidas no efeito relaxante do EHJ.

Background: Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified. Objectives: To determine the effects of jabuticaba hydroalcoholic extract (JHE) on vascular smooth muscle (VSM) of isolated arteries. Methods: Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed. Results: Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL). Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine) hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM). Conclusion: JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect. Resumo Fundamentos: Embora a jabuticaba apresente importantes efeitos biológicos, suas ações sobre o sistema cardiovascular ainda não foram esclarecidas. Objetivos: Determinar os efeitos do extrato de jabuticaba (EHJ) sobre o músculo liso vascular (MLV) em artérias isoladas. Métodos: Aortas (sem endotélio) de ratos foram montadas em banho de órgãos isolados para registro de tensão isométrica. Foram verificados o efeito relaxante, a influência dos canais de K+ e das fontes de Ca2+ intra- e extracelular sob a resposta estimulada pelo EHJ. Resultados: Artérias pré-contraídas com fenilefrina apresentaram relaxamento concentração-dependente (0,380 a 1,92 mg/mL). O tratamento com bloqueadores de canais de K+ (tetraetilamônio, glibenclamida, 4-aminopiridina) prejudicaram o relaxamento pelo EHJ. A contração estimulada com fenilefrina também foi prejudicada pelo tratamento prévio com EHJ. A inibição da Ca2+ATPase do reticulo sarcoplasmático não alterou o relaxamento pelo EHJ. Além disso, o EHJ inibiu a contração causada pelo influxo de Ca2+ estimulado por fenilefrina e KCl (75 mM). Conclusão: O EHJ induz vasodilatação independente do endotélio. Ativação dos canais de K+ e inibição do influxo de Ca2+ através da membrana estão envolvidas no efeito relaxante do EHJ.

Producción Científica, Increased vascular tone in essential hypertension involves a sustained rise in total peripheral resistance. A model has been proposed in which the combination of membrane depolarization and higher L‐type Ca2+ channel activity generates augmented Ca2+ influx into vascular smooth muscle cells (VSMCs), contraction and vasoconstriction. The search for culprit ion channels responsible for membrane depolarization has provided several candidates, including members of the canonical transient receptor potential (TRPC) family. TRPC3 and TRPC6 are diacylglycerol‐activated, non‐selective cationic channels contributing to stretch‐ or agonist‐induced depolarization. Conflicting information exists regarding changes in TRPC3/TRPC6 functional expression in hypertension. However, although TRPC3‐TRPC6 channels can heteromultimerize, the possibility that differences in their association pattern may change their functional contribution to vascular tone is largely unexplored. We probe this hypothesis using a model of essential hypertension (BPH mice; blood pressure high) and its normotensive control (BPN mice; blood pressure normal). First, non‐selective cationic currents through homo‐ and heterotetramers recorded from transfected Chinese hamster ovary cells indicated that TRPC currents were sensitive to the selective antagonist Pyr10 only when TRPC6 was present, whereas intracellular anti‐TRPC3 antibody selectively blocked TRPC3‐mediated currents. In mesenteric VSMCs, basal and agonist‐induced currents were more sensitive to Pyr3 and Pyr10 in BPN cells. Consistently, myography studies showed a larger Pyr3/10‐induced vasodilatation in BPN mesenteric arteries. mRNA and protein expression data supported changes in TRPC3 and TRPC6 proportions and assembly, with a higher TRPC3 channel contribution in BPH VSMCs that could favour cell depolarization. These differences in functional and pharmacological properties of TRPC3 and TRPC6 channels, depending on their assembly, could represent novel therapeutical opportunities., Instituto de Salud Carlos III (project RD12/0042/0006), Programa Estatal de Investigación (project BFU2013-45867-R )

Introduction Diabetes‐induced erectile dysfunction involves elevated arginase (Arg) activity and expression. Because nitric oxide (NO) synthase and Arg share and compete for their substrate L‐arginine, NO production is likely linked to regulation of Arg. Arg is highly expressed and implicated in erectile dysfunction. Aim It was hypothesized that Arg‐II isoform deletion enhances relaxation function of corpora cavernosal (CC) smooth muscle in a streptozotocin (STZ) diabetic model. Methods Eight weeks after STZ‐induced diabetes, vascular functional studies, Arg activity assay, and protein expression levels of Arg and constitutive NOS (using Western blots) were assessed in CC tissues from nondiabetic wild type (WT), diabetic (D) WT (WT + D), Arg‐II knockout (KO), and Arg‐II KO+D mice (N = 8–10 per group). Main Outcome Measures Inhibition or lack of arginase results in facilitation of CC relaxation in diabetic CC. Results Strips of CC from Arg‐II KO mice exhibited an enhanced maximum endothelium‐dependent relaxation (from 70 + 3% to 84 + 4%) and increased nitrergic relaxation (by 55%, 71%, 42%, 42%, and 24% for 1, 2, 4, 8 and 16 Hz, respectively) compared with WT mice. WT + D mice showed a significant reduction of endothelium‐dependent maximum relaxation (44 + 8%), but this impairment of relaxation was significantly prevented in Arg‐II KO+D mice (69 + 4%). Sympathetic‐mediated and alpha‐adrenergic agent‐induced contractile responses also were increased in CC strips from D compared with non‐D controls. Contractile responses were significantly lower in Arg‐II KO control and D versus the WT groups. WT + D mice increased Arg activity (1.5‐fold) and Arg‐II protein expression and decreased total and phospho‐eNOS at Ser‐1177, and nNOS levels. These alterations were not seen in Arg‐II KO mice. Additionally, the Arg inhibitor BEC (50 µM) enhanced nitrergic and endothelium‐dependent relaxation in CC of WT + D mice. Conclusion These studies show for the first time that Arg‐II deletion improves CC relaxation in type 1 diabetes. Toque HA, Tostes RC, Yao L, Xu Z‐M, Webb RC, Caldwell RB, and Caldwell RW. Arginase II deletion increases corpora cavernosa relaxation in diabetic mice.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:43:28Z No. of bitstreams: 1 S1677-54492010000200007.pdf: 388797 bytes, checksum: 0ece62463b50f3d0e9e4823d2bf333c3 (MD5) Made available in DSpace on 2013-08-22T18:43:28Z (GMT). No. of bitstreams: 1 S1677-54492010000200007.pdf: 388797 bytes, checksum: 0ece62463b50f3d0e9e4823d2bf333c3 (MD5) Previous issue date: 2010-06-01 Made available in DSpace on 2013-09-30T19:31:08Z (GMT). No. of bitstreams: 2 S1677-54492010000200007.pdf: 388797 bytes, checksum: 0ece62463b50f3d0e9e4823d2bf333c3 (MD5) S1677-54492010000200007.pdf.txt: 51530 bytes, checksum: 972322a62fec5c4e2995206553d62bd6 (MD5) Previous issue date: 2010-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:08:32Z No. of bitstreams: 2 S1677-54492010000200007.pdf: 388797 bytes, checksum: 0ece62463b50f3d0e9e4823d2bf333c3 (MD5) S1677-54492010000200007.pdf.txt: 51530 bytes, checksum: 972322a62fec5c4e2995206553d62bd6 (MD5) Made available in DSpace on 2014-05-20T15:08:32Z (GMT). No. of bitstreams: 2 S1677-54492010000200007.pdf: 388797 bytes, checksum: 0ece62463b50f3d0e9e4823d2bf333c3 (MD5) S1677-54492010000200007.pdf.txt: 51530 bytes, checksum: 972322a62fec5c4e2995206553d62bd6 (MD5) Previous issue date: 2010-06-01 O exercício aeróbio promove efeitos benéficos na prevenção e tratamento de doenças como hipertensão arterial, aterosclerose, insuficiência venosa e doença arterial periférica. Os receptores β-adrenérgicos estão presentes em várias células. No sistema cardiovascular, promovem inotropismo e cronotropismo positivo cardíaco e relaxamento vascular. Embora os efeitos do exercício tenham sido investigados em receptores cardíacos, estudos focados nos vasos são escassos e controversos. Esta revisão abordará os efeitos do exercício físico sobre os receptores β-adrenérgicos vasculares em modelos animais e humanos e os mecanismos celulares envolvidos na resposta relaxante. em geral, os estudos mostram resultantes conflitantes, onde observam diminuição, aumento ou nenhum efeito do exercício físico sobre a resposta relaxante. Assim, os efeitos do exercício na sensibilidade β-adrenérgica vascular merecem maior atenção, e os resultados mostram que a área de fisiopatologia vascular é um campo aberto para a descoberta de novos compostos e avanços na prática clínica. Aerobic exercise promotes beneficial effects on the prevention and treatment of diseases such as arterial hypertension, atherosclerosis, venous insufficiency, and peripheral arterial disease. β-adrenergic receptors are present in a variety of cells. In the cardiovascular system, β-adrenergic receptors promote positive inotropic and chronotropic response and vasorelaxation. Although the effect of exercise training has been largely studied in the cardiac tissue, studies focused on the vascular tissue are rare and controversial. This review examines the data from studies using animal and human models to determine the effect of physical exercise on the relaxing response mediated by β-adrenergic receptors as well as the cellular mechanisms involved in this response. Studies have shown reduction, increase, or no effect of physical exercise on the relaxing response mediated by β-adrenergic receptors. Thus, the effects of exercise on the vascular β-adrenergic sensitivity should be more deeply investigated. Furthermore, the physiopathology of the vascular system is an open field for the discovery of new compounds and advances in the clinical practice. Universidade Estadual Paulista Instituto de Biociências Departamento de Educação Física Universidade Estadual Paulista Instituto de Biociências Departamento de Educação Física

Previous findings enable us to hypothesize that (−)-α-bisabolol acts as inhibitor of voltage-dependent Ca2+ channels in smooth muscle. The current studywas aimed at consolidating such hypothesis through the recording of isometric tension, measurement of intracellular Ca2+ as well as discovery of channel target using in silico analysis. In rat aortic rings, (−)-α-bisabolol (1–1000 μM) relaxed KCl- and phenylephrine-elicited contractions, but the IC50 differed significantly (22.8 [17.6–27.7] and 200.7 [120.4–334.6] μM, respectively). The relaxation of phenylephrine contractions remained unaffected by L-NAME, indomethacin, 1H-[1,2,4]oxadiazolo[4,3-a] quinoxalin-1-one, tetraethylammonium, glibenclamide or KT-5720. Under Ca2+-free conditions, (−)-α- bisabolol did not alter the contractions evoked by phenylephrine or caffeine whereas it reduced those evoked by CaCl2 in KCl-, but not in PHE-stimulated preparations. Furthermore, it did not significantly alter the contractions evoked by phorbol 12,13-dibutyrate or induced by the extracellular Ca2+ restoration in cyclopiazonic acidtreated preparations. In mesenteric rings loaded with Fluo-4 AM, (−)-α-bisabolol blunted the tension and the cytosolic levels of Ca2+ in response to K+ but not to norepinephrine. Silico docking analysis of the Cavβ2a subunit of voltage-dependent Ca2+ channel indicated putative docking sites for (−)-α-bisabolol. These findings reinforce the ability of (−)-α-bisabolol to inhibit preferentially contractile responses evoked by Ca2+ influx through voltage-dependent Ca2+ channels.

La endotelina es un péptido vasoconstrictor aislado inicialmente del cerdo de donde procede su denominación. Es considerado como el más potente vasoconstrictor conocido por el hombre, es incluso 10 veces más potente que la angiotensina II. Existen tres isoformas y están distribuidas en diversas células y tejidos interviniendo en la modulación del tono vascular, proliferación celular, producción hormonal, balance del sodio y como neurotransmisor. Para la regulación del tono vascular debe de haber un equilibrio de fuerzas vasoconstrictoras y vasodilatadoras generados por el endotelio o que ejercen influencia sobre el mismo, existen varios candidatos en la categoría de los vasoconstrictores, pero el más importante es la endotelina-1 por su potencia y su localización, ya que su acción es ejercida sobre el músculo liso vascular. Endothelin is a vasoconstrictor peptide originally isolated pig whence its name. It is considered the most potent vasoconstrictor known to man, is even 10 times more potent than angiotensin II. There are three isoforms and are distributed invarious cells and tissues interveningin the modulation of vascular tone, cell proliferation, hormone production, sodium balanceandas a neurotransmitter. For the regulation of vascular tone must have a balance of vasoconstrictor and vasodilator forces generated by the endothelium or that influence it, there are several candidates in the category of vasoconstrictors, but the most important is theendothelin-1for its power and its location to beexertedits action on vascular smooth muscle. A endotelina é um peptídeo vasoconstritor, originalmente isolada de porco deu origem ao seu nome. Ele é considerado como o vasoconstritor mais potente conhecido do homem, é até 10 vezes mais potente que a angiotensina II. Existem três isoformas e são distribuídas em várias células e tecidos que intervêm na modulação do tónus vascular, proliferação celular, a produção da hormona, o balanço de sódio como um neurotransmissor. Para a regulação do tônus vascular vários candidatos devem ter um saldo de vasoconstrição e vasodilatação forças geradas pelo endotélio ou que a influência dele, existe na categoria de vasoconstritores, mas o mais importante é a endotelina-1 em seu poder e localização, como sua ação é exercida sobre o músculo liso vascular.

Cardiovascular effects of the linalool-rich essential oil of Aniba rosaeodora (here named as EOAR) in normotensive rats were investigated. In anesthetized rats, intravenous (i.v.) injection of EOAR induced dosedependent biphasic hypotension and bradycardia. Emphasis was given to the first phase (phase 1) of the cardiovascular effects, which is rapid (onset time of 1–3 s) and not observed in animals submitted to bilateral vagotomy or selective blockade of neural conduction of vagal C-fibre afferents by perineural treatment with capsaicin. Phase 1 was also absent when EOAR was directly injected into the left ventricle injection, but it was unaltered by i.v. pretreatment with capsazepine, ondansetron or HC030031. In conscious rats, EOAR induced rapid and monophasic hypotensive and bradycardiac (phase 1) effects that were abolished by i.v. methylatropine. In endothelium- intact aortic rings, EOAR fully relaxed phenylephrine-induced contractions in a concentrationdependent manner. The present findings reveal that phase 1 of the bradycardiac and depressor responses induced by EOAR has a vago-vagal reflex origin resulting from the vagal pulmonary afferents stimulation. Such phenomenon appears not to involve the recruitment of C-fibre afferents expressing 5HT3 receptors or the two chemosensory ion channels TRPV1 and TRPA1. Phase 2 hypotensive response appears resulting from a direct vasodilatory action. Copyright © 2013 John Wiley & Sons, Ltd.

Producción Científica, Objective: Phenotypic modulation of vascular smooth muscle cells has been associated with a decreased expression of all voltage-dependent potassium channel (Kv)1 channel encoding genes but Kcna3 (which encodes Kv1.3 channels). In fact, upregulation of Kv1.3 currents seems to be important to modulate proliferation of mice femoral vascular smooth muscle cells in culture. This study was designed to explore if these changes in Kv1 expression pattern constituted a landmark of phenotypic modulation across vascular beds and to investigate the mechanisms involved in the proproliferative function of Kv1.3 channels. Methods and Results: Changes in Kv1.3 and Kv1.5 channel expression were reproduced in mesenteric and aortic vascular smooth muscle cells, and their correlate with protein expression was electrophysiologicaly confirmed using selective blockers. Heterologous expression of Kv1.3 and Kv1.5 channels in HEK cells has opposite effects on the proliferation rate. The proproliferative effect of Kv1.3 channels was reproduced by “poreless” mutants but disappeared when voltagedependence of gating was suppressed. Conclusion: These findings suggest that the signaling cascade linking Kv1.3 functional expression to cell proliferation is activated by the voltage-dependent conformational change of the channels without needing ion conduction. Additionally, the conserved upregulation of Kv1.3 on phenotypic modulation in several vascular beds makes this channel a good target to control unwanted vascular remodeling., Instituto de Salud Carlos III (grant R006/009), Ministerio de Ciencia, Innovación y Universidades (grant BFU2010-15898), Junta de Castilla y León (grant VA094A11-2)

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