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1.
Am J Physiol Heart Circ Physiol ; 322(4): H523-H536, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35119333

RESUMO

Prolonged high-fat diet (HFD) accelerates the cardiovascular, renal, and metabolic dysfunction in hypertensive rats with altered renal development (ARDev). Soluble guanylate cyclase (sGC) stimulation or sodium-glucose cotransporter 2 (SGLT2) inhibition may improve cardiovascular, renal, and metabolic function in settings of hypertension and obesity. This study examined whether 6 wk treatment with an SGLT2 inhibitor (empagliflozin, 7 mg/kg/day) enhances the cardiovascular, renal, and metabolic effects of a sGC stimulator (praliciguat, 10 mg/kg/day) in hypertensive rats with ARDev and prolonged exposure to HFD. Arterial pressure (AP), renal vascular resistance (RVR), fat abdominal volume (FAV), insulin resistance, leptin and triglycerides levels, and intrarenal infiltration of inflammatory cells were higher, but cardiac output and creatinine clearance were lower in hypertensive rats (n = 15) than in normotensive rats (n = 7). Praliciguat administration (n = 10) to hypertensive rats reduced (P < 0.05) AP, FAV, plasma concentrations of leptin and triglycerides, and increased (P < 0.05) cardiac output and creatinine clearance. Empagliflozin administration (n = 8) only increased (P < 0.05) glucosuria and creatinine clearance and decreased (P < 0.05) plasma leptin and triglycerides concentrations in hypertensive rats. Simultaneous administration of praliciguat and empagliflozin (n = 10) accelerated the decrease in AP, improved glucose tolerance, reduced (P < 0.05) incremental body weight gain, and decreased (P < 0.05) insulin resistance index, RVR, and the infiltration of T-CD3 lymphocytes in renal cortex and renal medulla. In summary, the combined administration of praliciguat and empagliflozin leads to a greater improvement of the cardiovascular, renal, and metabolic dysfunction secondary to prolonged exposure to HFD in hypertensive rats with ARDev than the treatment with either praliciguat or empagliflozin alone.NEW & NOTEWORTHY This is the first study, to our knowledge, showing that SGLT2 inhibition potentiates the beneficial cardiovascular, renal, and metabolic effects elicited by sGC stimulation in hypertensive rats with prolonged high-fat diet. The effects of the simultaneous administration of praliciguat and empagliflozin are greater than those elicited by either one alone. The effects of the simultaneous treatment may be related to a greater reduction in the inflammatory status.


Assuntos
Hipertensão , Resistência à Insulina , Animais , Compostos Benzidrílicos/farmacologia , Creatinina , Dieta Hiperlipídica/efeitos adversos , Glucose , Leptina , Ratos , Transportador 2 de Glucose-Sódio , Guanilil Ciclase Solúvel , Triglicerídeos
2.
J Physiol Biochem ; 77(3): 431-441, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33851366

RESUMO

The mechanisms involved in renal dysfunction induced by high-fat diet (HFD) in subjects with altered renal development (ARDev) are understudied. The objective of this study is to examine whether there are sex-dependent differences in the mechanisms involved in the hypertension and deterioration of renal function in SD rats with prolonged HFD and ARDev. The role of angiotensin II (Ang II) in the arterial pressure (AP) increments, the renal hemodynamic sensitivity to Ang II, glomerular damage and changes in fat abdominal volume, plasma adipokine levels, renal NADPHp67phox expression, and renal infiltration of immune cells were examined. Hypertension and deterioration of renal function were enhanced (P < 0.05) in both sexes of rats with HFD and ARDev. The decrease (P < 0.05) of AP elicited by candesartan in hypertensive rats was similar to that induced by the simultaneous administration of candesartan and apocynin. The greater (P < 0.05) renal vasoconstriction induced by Ang II in both sexes of rats with HFD and ARDev was accompanied by an enhanced (P < 0.05) infiltration of CD-3 cells and macrophages in the renal cortex and renal medulla. The increments (P < 0.05) in the renal expression of NADPHp67phox and glomeruloesclerosis were greater (P < 0.05) in males than in females with HFD and ARDev. Our results suggest that the hypertension and deterioration of renal function induced by HFD in rats with ARDev are Ang II-dependent and mediated by increments in oxidative stress and immune system activation. Sex-dependent increments in oxidative stress and glomerular damage may contribute to the deterioration of renal function in these rats.


Assuntos
Dieta Hiperlipídica , Hipertensão/fisiopatologia , Nefropatias/fisiopatologia , Rim , Fatores Sexuais , Animais , Feminino , Rim/fisiopatologia , Masculino , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley
4.
PLoS One ; 15(6): e0234861, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32603330

RESUMO

OBJECTIVE: To examine whether the cardiac, renal and uterine physiological hemodynamic changes during gestation are altered in rats with an early and prolonged exposure to a high fat diet (HFD). METHODS: Arterial pressure and cardiac, renal, uterine and radial arteries hemodynamic changes during gestation were examined in adult SD rats exposed to normal (13%) (n = 8) or high (60%) (n = 8) fat diets from weaning. Plethysmography, high-resolution high-frequency ultrasonography and clearance of an inulin analog were used to evaluate the arterial pressure and hemodynamic changes before and at days 7, 14 and 19 of gestation. RESULTS: Arterial pressure was higher (P<0.05) in rats with high than in those with normal (NFD) fat diet before pregnancy (123 ±3 and 110 ±3 mmHg, respectively) and only decreased at day 14 of gestation in rats with NFD (98±4 mmHg, P<0.05). A significant increment in stroke volume (42 ±10%) and cardiac output (51 ±12%) was found at day 19 of pregnancy in rats with NFD. The changes in stroke volume and cardiac output were similar in rats with NFD and HFD. When compared to the values obtained before pregnancy, a transitory elevation in renal blood flow was found at day 14 of pregnancy in both groups. However, glomerular filtration rate only increased (P<0.05) in rats with NFD at days 14 (20 ±7%) and 19 (27 ±8%) of gestation. The significant elevations of mean velocity, and velocity time integral throughout gestation in radial (127 ±26% and 111 ±23%, respectively) and uterine (91 ±16% and 111 ±25%, respectively) arteries of rats with NFD were not found in rats with an early and prolonged HFD. SUMMARY: This study reports novel findings showing that the early and prolonged exposure to a HFD leads to a significant impairment in the renal, uterine and radial arteries hemodynamic changes associated to gestation.


Assuntos
Artérias/fisiopatologia , Vasos Coronários/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Artérias/diagnóstico por imagem , Pressão Sanguínea/fisiologia , Vasos Coronários/diagnóstico por imagem , Feminino , Taxa de Filtração Glomerular/fisiologia , Rim/irrigação sanguínea , Modelos Animais , Gravidez , Ratos , Fluxo Sanguíneo Regional/fisiologia , Volume Sistólico/fisiologia , Ultrassonografia , Útero/irrigação sanguínea , Útero/diagnóstico por imagem
5.
Am J Physiol Renal Physiol ; 316(2): F332-F340, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30516421

RESUMO

This study examines whether the intake of a high-fat diet very early in life leads to changes in arterial pressure and renal function and evaluates whether the mechanisms involved in these changes are sex-dependent. Experiments were performed in male and female Sprague-Dawley rats fed a normal or high-fat diet from weaning to 4 mo of age. This exposure to a high-fat diet lead to an angiotensin II-dependent elevation in arterial pressure and to significant increments in fat abdominal volume and plasma leptin that were similar in both sexes. In addition, the angiotensin II-induced increment in renal vascular resistance was greater ( P < 0.05) in male (106 ± 14%) and female (97 ± 15%) rats fed a high-fat diet than in rats fed a normal-fat diet (51 ± 8%). However, the high-fat intake during early life induced increments in albuminuria, interleukin-6, and infiltration of CD3 lymphocytes in the renal parenchyma that were greater ( P < 0.05) in male than in female rats. Other sex-dependent differences in response to high-fat intake were that adiponectin levels only decreased in females (21%, P < 0.05), and renal NF-κB expression only increased in males (31%, P < 0.05). In summary, the early exposure to a high-fat diet leads to angiotensin II-dependent arterial pressure elevations and to increments in abdominal fat and in the renal sensitivity to angiotensin II that are similar in both sexes. However, the mechanisms involved in the renal changes associated with early exposure to a high-fat diet are different in males and females.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Hipertensão/etiologia , Nefropatias/etiologia , Rim/fisiopatologia , Obesidade/etiologia , Gordura Abdominal/fisiopatologia , Adipocinas/sangue , Adiposidade , Fatores Etários , Albuminúria/etiologia , Albuminúria/fisiopatologia , Angiotensina II/toxicidade , Animais , Pressão Arterial , Progressão da Doença , Feminino , Hipertensão/sangue , Hipertensão/fisiopatologia , Mediadores da Inflamação/sangue , Rim/metabolismo , Nefropatias/sangue , Nefropatias/fisiopatologia , Masculino , Obesidade/sangue , Obesidade/fisiopatologia , Ratos Sprague-Dawley , Fatores Sexuais , Fatores de Tempo
6.
J. physiol. biochem ; 72(1): 1-8, mar. 2016. tab, graf
Artigo em Inglês | IBECS | ID: ibc-168202

RESUMO

Regulation of medullary blood flow (MBF) is essential in maintaining renal function and blood pressure. However, it is unknown whether outer MBF (OMBF) and papillary blood flow (PBF) are regulated independently when extracellular volume (ECV) is enhanced. The aim of this study was to determine whether OMBF and PBF are differently regulated and whether there is an interaction between nitric oxide (NO), prostaglandins (PGs) and angiotensin II (Ang II) in regulating OMBF and PBF when ECV is enhanced. To achieve these goals, OMBF and PBF were measured by laser-Doppler in volume-expanded rats treated with a cyclooxygenase inhibitor (meclofenamate, 3 mg/kg) and/or a NO synthesis inhibitor (L-nitro-arginine methyl ester (L-NAME), 3 μg/kg/min) and/or Ang II (10 ng/kg/min). OMBF was unchanged by NO or PGs synthesis inhibition but decreased by 36 % (P < 0.05) when L-NAME and meclofenamate were infused simultaneously. PBF was similarly reduced by L-NAME (12 %), meclofenamate (17 %) or L-NAME + meclofenamate (19 %). Ang II did not modify OMBF, but it led to a similar decrease (P < 0.05) in OMBF when it was administered to rats with reduced NO (32 %), PGs (36 %) or NO and PGs (37 %) synthesis. In contrast, the fall in PBF induced by Ang II (12 %) was enhanced (P < 0.05) by the simultaneous PGs (30 %) or PGs and NO (31 %) synthesis inhibition but not in L-NAME-treated rats (20 %). This study presents novel findings suggesting that blood flows to the outer medulla and renal papilla are differently regulated and showing that there is a complex interaction between NO, PGs and Ang II in regulating OMBF and PBF when ECV is enhanced (AU)


Assuntos
Animais , Masculino , Ratos , Óxido Nítrico/fisiologia , Prostaglandinas/fisiologia , Angiotensina II/fisiologia , Medula Renal/irrigação sanguínea , Fluxo Sanguíneo Regional/fisiologia , Ratos Wistar , Taxa de Filtração Glomerular
7.
J Physiol Biochem ; 72(1): 1-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26611113

RESUMO

Regulation of medullary blood flow (MBF) is essential in maintaining renal function and blood pressure. However, it is unknown whether outer MBF (OMBF) and papillary blood flow (PBF) are regulated independently when extracellular volume (ECV) is enhanced. The aim of this study was to determine whether OMBF and PBF are differently regulated and whether there is an interaction between nitric oxide (NO), prostaglandins (PGs) and angiotensin II (Ang II) in regulating OMBF and PBF when ECV is enhanced. To achieve these goals, OMBF and PBF were measured by laser-Doppler in volume-expanded rats treated with a cyclooxygenase inhibitor (meclofenamate, 3 mg/kg) and/or a NO synthesis inhibitor (L-nitro-arginine methyl ester (L-NAME), 3 µg/kg/min) and/or Ang II (10 ng/kg/min). OMBF was unchanged by NO or PGs synthesis inhibition but decreased by 36 % (P < 0.05) when L-NAME and meclofenamate were infused simultaneously. PBF was similarly reduced by L-NAME (12 %), meclofenamate (17 %) or L-NAME + meclofenamate (19 %). Ang II did not modify OMBF, but it led to a similar decrease (P < 0.05) in OMBF when it was administered to rats with reduced NO (32 %), PGs (36 %) or NO and PGs (37 %) synthesis. In contrast, the fall in PBF induced by Ang II (12 %) was enhanced (P < 0.05) by the simultaneous PGs (30 %) or PGs and NO (31 %) synthesis inhibition but not in L-NAME-treated rats (20 %). This study presents novel findings suggesting that blood flows to the outer medulla and renal papilla are differently regulated and showing that there is a complex interaction between NO, PGs and Ang II in regulating OMBF and PBF when ECV is enhanced.


Assuntos
Angiotensina II/fisiologia , Medula Renal/irrigação sanguínea , Óxido Nítrico/fisiologia , Prostaglandinas/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Animais , Taxa de Filtração Glomerular , Masculino , Ratos , Ratos Wistar
8.
Psicol. conduct ; 19(3): 557-576, sept.-dic. 2011. tab
Artigo em Espanhol | IBECS | ID: ibc-113079

RESUMO

Este estudio tiene como objetivo analizar el síndrome del quemado, los modos de afrontamiento del estrés, la salud mental y, específicamente, detectar predictores de salud mental. Participaron 152 profesores no universitarios, de edades comprendidas entre los 24 y 58 años, a quienes se evaluó con el "Inventario de burnout de Maslach" (Maslach Burnout Inventory; Maslach y Jackson 1981), el "Cuestionario de modos de afrontamiento" (Ways of Coping of Questionnaire; Folkman y Lazarus, 1988) y el "Cuestionario de salud general (General Health Questionaire; Goldberg y William, 1996). Los resultados indican que el síndrome del quemado se presenta en grado medio, los modos de afrontamiento que más se utilizan son la búsqueda de apoyo social, planificación y reevaluación positiva y el 40,8% presenta problemas de salud mental. Además, se halló un alto nivel de estrés asociado con la estrategia de afrontamiento huida-evitación y que los profesores menos satisfechos profesionalmente son los más "quemados". Las variables puesto de trabajo, nivel de estrés, grado de compromiso, cansancio emocional, los modos de huida-evitación y reevaluación positiva contribuyen significativamente a predecir la salud mental del profesorado (AU)


The main objective of the present study was to analyze burnout syndrome, ways of coping with stress, mental health and, specifically, to detect mental health predictors. The sample consisted of 152 non-university teachers between 24 and 58 years of age. We performed a descriptive exploratory study using the Maslach Burnout Inventory (Maslach & Jackson, 1981), the Ways of Coping Questionnaire (Folkman & Lazarus, 1988), and the General Health Questionnaire (Goldberg y William, 1972). The results indicate that the sample of teachers presented a medium degree of burnout. The most frequent strategies of coping with stress are: seeking social support, planning, and positive reappraisal. 40.8% of the sample had mental health problems. It was also found that a high level of stress was significantly associated with the escape-avoidance coping strategy, and that those teachers who were the least satisfied professionally were the most "burnt-out". The variables of job, assessment of stress level, degree of commitment, emotional exhaustion, ways of coping escape-avoidance, and positive reappraisal contribute significantly to predict the teachers' mental health


Assuntos
Humanos , Esgotamento Profissional/epidemiologia , Estresse Psicológico/epidemiologia , Transtornos de Adaptação/epidemiologia , Docentes , 16359/análise , Satisfação no Emprego , Distribuição por Idade e Sexo , Fatores de Risco
9.
Am J Hypertens ; 23(8): 882-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20431527

RESUMO

BACKGROUND: We investigated the contribution of the sympathetic tone to the hypertension induced by chronic administration of buthionine sulfoximine (BSO) and characterized this model in mice. METHODS: Three experiments were performed. In experiment I, four groups of CBA-C57 male mice were used: controls and three groups that received oral BSO at 5, 10, or 20 mmol/l. In experiment II, the alpha(1)-adrenergic blocker prazosin was orally administered (10 mg/100 ml) to control and BSO-treated mice. All treatments were maintained for 5 weeks. Body weight (BW), tail blood pressure (BP), and heart rate (HR) were measured weekly. Direct mean arterial pressure (MAP) and morphological, metabolic, plasma, and renal variables were measured at the end of the experiments. In experiment III, the acute response of MAP and HR to the ganglionic blocker pentolinium (10 mg/kg intravenous) was used to further evaluate the sympathetic contribution to BP and HR in control and BSO-treated mice. RESULTS: BSO produced dose-related increases in BP (control, 115 +/- 0.5; BSO-5, 141 +/- 0.5; BSO-10, 151 +/- 0.9; BSO-20, 163 +/- 1.1 mm Hg) and HR and augmented plasma noradrenaline, brainstem isoprostane levels, and total urinary isoprostane excretion. BSO did not produce cardiac hypertrophy and did not modify metabolic or plasma variables, or creatinine clearance, proteinuria, or renal morphology. Chronic prazosin markedly reduced MAP (control, 101 +/- 4.7; prazosin, 95 +/- 1.29; BSO-10, 130 +/- 2.9; BSO-10 +/- prazosin, 98 +/- 0.9) and HR. Acute pentolinium produced a greater percentage MAP (control, 43 +/- 4.2; BSO-10, 66 +/- 4.5) and HR decrease in BSO-treated mice vs. controls. CONCLUSION: Sympathetic tone plays a major role in the increased BP and HR of BSO hypertensive mice.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hipertensão/fisiopatologia , Sistema Nervoso Simpático/fisiologia , Antagonistas de Receptores Adrenérgicos alfa 1 , Animais , Butionina Sulfoximina , Bloqueadores Ganglionares/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Hipertensão/induzido quimicamente , Isoprostanos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos CBA , Estresse Oxidativo/fisiologia , Tartarato de Pentolínio/farmacologia , Prazosina/farmacologia
10.
Anim Reprod Sci ; 112(3-4): 347-61, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18585877

RESUMO

This work presents a Biological Resource Bank generated as a complementary supporting tool for the reproduction and the in situ and ex situ conservation of the Iberian lynx. In its design we prioritized the preservation of a maximum of the current genetic and biological diversity of the population, and the harmless collection of the samples. To provide future reproductive opportunities through any possible technique, we processed and cryopreserved germinal cells and tissues from dead animals, 7 males and 6 females, as well as somatic cells and tissues from 69 different individuals. This somatic cell reserve reflects a very important fraction of the population biodiversity which, furthermore, will allow the development of a wide variety of studies that can be easily extrapolated to the majority of the population. We have developed a new non-destructive method to isolate cells with stem-cell-like properties. If considered convenient in the future, and after proper research, such cells could permit therapeutic applications and perhaps be a good source to be used in somatic cell nuclear transfer. Samples of whole blood and its derivatives, hairs, urine and feces from many different individuals were also preserved. Proper storage of such samples is required to allow epidemiological studies to be performed for the testing of different etiological hypotheses or, in general, to develop any bio-sanitary study to improve conservation strategies within the natural habitat. This work describes the main aspects involved in the practical implementation of the Iberian lynx Biological Resource Bank, as a model that could be useful for the development of similar banks for other endangered species.


Assuntos
Animais Selvagens , Bancos de Espécimes Biológicos , Conservação dos Recursos Naturais/métodos , Extinção Biológica , Lynx/fisiologia , Técnicas de Reprodução Assistida , Animais , Animais Selvagens/fisiologia , Bancos de Espécimes Biológicos/provisão & distribuição , Feminino , Células Germinativas/citologia , Células Germinativas/fisiologia , Masculino , Técnicas de Transferência Nuclear/veterinária , Reprodução/fisiologia , Coleta de Tecidos e Órgãos/métodos , Coleta de Tecidos e Órgãos/veterinária
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