Mestrado em Ciências Fisiológicas

URI Permanente para esta coleção

http://repositorio.ufes.br/handle/10/17572

Nível: Mestrado Acadêmico
Ano de início:
Conceito atual na CAPES:
Ato normativo:
Periodicidade de seleção:
Área(s) de concentração:
Url do curso:

Navegar

Agora exibindo 1 - 7 de 7

A exposição única ao contaminante ambiental tributilestanho induz disfunção endotelial e estresse oxidativo em aorta
(Universidade Federal do Espírito Santo, 2018-09-27) Santos, Gersica de Almeida Correia; Ribeiro Júnior, Rogério Faustino; Stefanon, Ivanita; Andrade, Tadeu Uggere de; Rodrigues, Lívia Carla de Melo
INTRODUCTION: Organotins such as tributyltin (TBT) are environmental contaminants with a cytotoxic effect. Animals chronically exposed to TBT have vascular reactivity dysfunction associated with increased production of reactive oxygen species (ROS). The aim of this study was to investigate the effect of a single exposure to TBT. Vascular reactivity of isolated female rat aorta rings was evaluated 24 hours after exposure to a single dose of TBT (500 ng / kg) per gavage. METHOD: Wistar rats (240-260 g) were divided into control (CT) groups, and exposed to a single dose of TBT. The aorta was isolated and cut into rings, which were immersed in Krebs solution submitted to the concentration response curve of phenylephrine, LNG-nitroarginine methyl ester (L-NAME), Apocynine, Tiron and Losartan. The vasodilatory response was assessed by relaxing the increasing doses of Acetylcholine (ACh). In addition, the presence of ROS was measured by the intensity of the fluorescence produced by the oxidation of the dihydroetide (DHE). Data were expressed as mean ± SEM and analyzed by 2-way ANOVA or unpaired t-test with significance of p <0.05. The protocols were approved by the Ethics Committee on Animal Experimentation UFES (Protocols 27/2016). RESULTS: The aortic rings from the TBT group showed reduction of sensitivity (pD2) and the maximum response (Rmax) to ACh (pD2 TBT: 6.37 ± 0.27 * vs CT: 7.3 ± 0.25; Rmax TBT: 77 ± 5,18 * vs. CT: 92.9 ± 1.88 *, * p <0.05 vs CT), and increased maximal response and phenilefrine sensitivity (Rmax: TBT: 142 ± 7.2 ** vs CT : 110 ± 4% KCl, ** p <0.01; pD2: TBT: 7.68 ± 0.08 * vs. CT: 7.19 ± 0.13% KCl, * p <0.05 vs. CT). A incubation of the aortic rings with L-NAME increased the reactivity to phenilefrine in both groups (Rmax TBT: 142.2 ± 7.2 vs TBT L-NAME: 175 ± 7.8 # and CT: 110 ± 4 vs. CT LNAME: 165 , 7 ± 8.6 **% KCl, # p <0.05 vs TBT, ** p <0.01 vs CT). However, the area under the curve (dAUC %) was lower in the TBT vs CT group (CT: 52.4 ± 4.61 vs TBT: 35.8 ± 4.31 * p <0.05). The maximum response to phenilefrine was reduced in the TBT group after incubation with Apocinin, Tiron, Catalase and Losartan (TBT: 142 ± 7.2 vs TBT APO: 102.9 ± 5.42 # # TBT TIRON: 104.3 ± 9, TBT: 101.8 ± 7.38 % KCl; # # p <0.01 vs TBT). ROS was increased in the aorta of the animals exposed to TBT. CONCLUSION: We conclude that 24 hours after exposure to a single dose of 20 500 ng / kg TBT causes endothelial dysfunction, increase in the vasoconstrictor response to phenylephrine and a reduction in the vasodilatory response to acetylcholine that appears to be mediated by vascular oxidative stress.
Avaliação dos efeitos tóxicos da exposição ao inseticida, fosforoamidotioato de O,S-Dimetila (Metamidofós) sobre o reflexo Bezold-Jarisch e sobre o quimiorreflexo em animais experimentais
(Universidade Federal do Espírito Santo, 2012-06-29) Pinheiro, Gabriella Xavier Maretto; Sampaio, Karla Nívea; Figueiredo, Suely Gomes de; Vasquez, Elisardo Corral; Andrade, Tadeu Uggere de
Poisoning by organophosphate pesticides is often accompanied by cardiac complications which may be serious and even fatal. However, the effects of these compounds on the cardiovascular mechanisms involved in blood pressure regulation remain unknown. The aim of this study was to evaluate the effects of the administration of a single sublethal dose (8 mg/kg, i.p.) of the organophosphorus insecticide methamidophos on the Bezold-Jarisch reflex (BJR) and on the chemoreflex, as well as the effects of this administration on the activity of the plasma cholinesterase (ChE), creatin kinase-MB (CK-MB) and lactate dehydrogenase (LDH). For the protocols involving the cardiovascular reflexes, male Wistar rats were treated with single intraperitoneal injections of methamidophos (8 mg/kg; n=23; MTF group) or saline (0.9%, n=20; control group, CON). Twenty four hours after the injection procedure the animals underwent catheterization of the femoral artery and vein to allow pressure recordings and drugs administration, respectively. Cardiovascular recordings were performed 24 hours after the catheterization procedures. The chemoreflex and BJR were activated by intravenous (i.v.) injections randomly assigned of KCN (10, 20, 40 and 80 µg/rat) and phenylbiguanide (PBG, 1.5, 3, 6, 12 and 24 µg/kg), respectively. The bradycardic responses of the BJR were expressed as % of fall compared to baseline levels, while the chemoreflex responses were expressed as delta mean arterial pressure and heart rate. Separated groups of rats were treated similarly for the protocols involving measurement of the ChE (n=10/group), CK-MB (n=10/group) and LDH (n=9/group) and blood samples collected 24 h after the treatment. The statistical analysis used for the cardiovascular reflexes was one-way ANOVA for repeated measures followed by the Fisher's post hoc test and for the enzymatic protocols was the Student's t-test. The bradycardic component of the chemoreflex and of the BJR was significantly attenuated in animals treated with methamidophos. Similarly, the cholinesterase activity was significantly reduced in animals treated with this compound. However, no statistical differences were observed in the CK-MB and LDH activities between the studied groups (CON and MTF). Our data show that the acute treatment with methamidophos impairs the function of two cardiovascular reflexes, which could contribute to the cardiovascular complications observed in the acute poisoning by these compounds.
Efeito do tratamento com moduladores seletivos de receptores de estrogênio (SERMs) sobre a reatividade vascular e sobre os níveis séricos de citocinas pró-inflamatórias em ratas ovarectomizadas
(Universidade Federal do Espírito Santo, 2009-12-23) Lamas, Aline Zandonadi; Bissoli, Nazaré Souza; Graceli, Jones Bernardes; Andrade, Tadeu Uggere de
abstract
Efeitos cardiovasculares do tratamento crônico com testosterona em ratos wistar
(Universidade Federal do Espírito Santo, 2015-01-02) Rouver, Wender do Nascimento; Santos, Roger Lyrio dos; Moyses, Margareth Ribeiro; Andrade, Tadeu Uggere de; Graceli, Jones Bernardes
Cardiovascular diseases are the leading cause of death in world and the fact that men are more affected meant that the testosterone was thought of as a harmful substance to the cardiovascular system. However, more recent studies have challenged this hypothesis and suggest a beneficial role of this hormone on the cardiovascular system. Nevertheless, the effects of chronic testosterone treatment on vascular endothelium-dependent function, have not been fully clarified. Thus, the present study was designed to determine the effects of chronic treatment with different doses of testosterone on coronary vascular reactivity induced by bradykinin. Males Wistar rats were used with 10 weeks of age, who were separated in Sham and castrated groups. Castrated rats were immediately treated with physiological (Physio, 0.5 mg / kg / day, sc) and supraphysiological (Supra, 2.5 mg / kg / day, sc) doses of testosterone for 15 days. Systolic blood pressure (SBP) was measured by tail plethysmography at the end of treatment. After euthanasia, the hearts were removed and coronary vascular reactivity was assessed by retrograde perfusion technique Langendorff. Dose response curve of bradykinin (BK) was then constructed by inhibition with 100 mM L-NAME, 2.8 uM indomethacin (INDO), L-NAME + INDO or L-NAME + INDO + 0.75 uM clotrimazole (CLOT). Data were expressed as mean ± SEM and the comparison between groups was performed by one or two-way ANOVA followed by the post-hoc Tukey test (p <0.05). We observed significant coronary endothelium-dependent vasodilation induced by BK, which was abolished in castrated group and restored in Physio and Supra group. After conjugated inhibition of endothelium-dependent relaxation factors (NO, PGI2 and EDHF), we found that vasodilation was abolished in all groups. Castration modulated lipid and hormonal profile, as well as reduced body weight and replacement with testosterone was able to restore all of these parameters. We also observed a significant increase in blood pressure in Supra group. Our data lead us to conclude that testosterone physiological concentrations may play a beneficial role in cardiovascular system to maintain a favorable environment for the action of an endothelium-dependent vasodilator, with no increase in SBP, which makes this steroid a possible tool in hormone therapies.
Efeitos do tratamento crônico com tamoxifeno sobre a reatividade vascular do leito coronariano de ratas espontaneamente hipertensas
(Universidade Federal do Espírito Santo, 2009-12-17) Borgo, Mariana Veronez; Abreu, Glaucia Rodrigues de; Moyses, Margareth Ribeiro; Andrade, Tadeu Uggere de
Epidemiologic studies have demonstrated a decreased incidence of cardiovascular disease and risk factors in pre-menopausal women when compared with postmenopausal women. These results may be related, at least in part, with a significant decrease in the release of estrogen in menopause. Hormone reposition therapy (HRT) benefits metabolic and vascular factors, reducing the incidence of cardiovascular diseases. However, clinical trials are controversial as to their effects augmenting clinical interest over different replacement therapy low dose estrogen. Tamoxifen is a non-steroidal agent classified as a selective estrogen receptor modulator (SERM) for its specific actions, acting as an agonist or antagonist of estrogen receptors in deferent tissues. It is used as adjuvant therapy in estrogen dependent breast cancer, mostly in post-menopausal patients; however the cardiovascular effects of this drug have not been totally elucidated. The goal of this study is to identify the chronic tamoxifen effects on the blood pressure, cardiac function and coronary vascular reactivity. SHR rats were divided in four groups: control (SC), tamoxifen treated (ST), ovariectomized control (SOC) and ovariectomized tamoxifen treated (SOT). The animals were treated during 90 days using the gavage method. BP, HR, dP/dTmax and coronarian vascular reactivity, in Langendorff method isolated hearts were evaluated. The results demonstrated that tamoxifen attenuates the elevated blood pressure present in ovariectomized animals (SOC), reduces heart rate (HR) and the cardiac contractility index (dP/dTmax). Coronary vascular reactivity was also affected with reduced vasoconstriction to acetilcoline and increased vasodilation to adenosine. These results show the importance of the potential benefic effects of tamoxifen over coronarian vascular reactivity through mechanisms that may contribute to the protection against cardiovascular diseases and their risk factors.
Enalapril previne alterações cardiovasculares promovidas pelo tratamento crônico com doses suprafisiológicas de decanoato de nandrolona em ratos sedentários
(Universidade Federal do Espírito Santo, 2011-11-11) Loiola, Leonardo Zanoteli; Bissoli, Nazaré Souza; Andrade, Tadeu Uggere de; Lunz, Wellington; Garcia, Ana Raquel Santos de Medeiros
Nandrolone decanoate (ND) induces cardiovascular abnormalities, such as attenuation of the Bezold-Jarisch Reflex (BJR), cardiac hypertrophy and elevation of mean arterial pressure (MAP), and a relationship between androgens and the reninangiotensin system (RAS) has been reported. Objective: The purpose of this study was to evaluate the influence of RAS on the alterations in BJR, cardiac and prostatic hypertrophy and MAP evoked by ND. Methods: Male Wistar rats were treated with nandrolone decanoate (DECA; 10 mg/kg body.eight.week), and nandrolone plus enalapril (10 mg/kg body weight.day; DECAE) or vehicle (control animals; CON and CONE). After 8 weeks of treatment, the BJR was evaluated by bradycardia response elicited by serotonin administration (2–32 µg.kg-1 ). Mean arterial pressure (MAP) was assessed and cardiac hypertrophy was determined by the heart weight/body weight (HW/BW) ratio. Results: After eight weeks, Wistar rats treated with Nandrolone Decanoate showed increase on the mean arterial pressure, and enalapril was able to normalize it (CON = 98±1; CONE = 97±2; DECA = 109±2**; DECAE = 99±1 mmHg). This same behavior was verified on cardiac (CON = 2,52±0,05; CONE = 2,47±0,08; DECA = 2,78±0,06**; DECAE = 2,49±0,07) and prostatic (CON = 1,23±0,17; CONE = 1,23±0,09; DECA = 1,78±0,17**; DECAE = 1,36±0,14) hypertrophy. We also observed impairment in the BJR control of heart rate on the 8, 16 and 32 of 5-HT doses (S 8µg.Kg-1 : CON=-42±7%, CONE=-40±3%, DECA=-32±2%*, DECAE=- 41±2%; S 16µg.Kg-1 : CON=-54±4%, CONE=-55±6%, DECA=-44±2%, DECAE=- 53±2%; S 32µg.Kg-1 : CON=-71±3%, CONE=-68±2%, DECA=-59±2%, DECAE=- 68±2%, **p<0,01 *p<0,05 DECA animals related to CON, CONE and DECAE groups) and PAD on the 16 and 32 of 5-HT doses that also had been normalized in associated treatment with enalapril(S 16µg.Kg-1 : CON=-67±4%, CONE=-68±3%, DECA=-51±2%, DECAE=-63±3%; S 32µg.Kg-1 : CON=-81±2%, CONE=-75±3,2%, DECA=-62±3,1%, DECAE=-72±3,4%, **p<0,01 *p<0,05 DECA animals related to CON, CONE and DECAE groups). 13 Conclusions: Our results suggest that enalapril was able to normalize the MAP and the sensibility impairment of BJR, as well as prevent the development of cardiac and prostatic hypertrophy in rats whose alterations was resulted by nandrolone decanoate treatment.
Influência dos hormônios ovarianos na ação da Liraglutida no rim de ratas SHR
(Universidade Federal do Espírito Santo, 2023-09-26) Firmino, Felipe Tonon; Bissoli, Nazare Souza; http://lattes.cnpq.br/8865368585732583; http://lattes.cnpq.br/7614499614930821; Andrade, Tadeu Uggere de; Avila, Renata Andrade
GLP-1 receptor (glucagon-like peptide-1) agonists have beneficial cardiovascular effects through mechanisms other than glycemic control. However, the renal effects of the antidiabetic drug Liraglutide in a model of hypertension associated with ovarian hormone deficiency have not yet been investigated. SHR female rats (8 weeks old) were used. Ovariectomy or sham surgery were performed. The rats were separated into: saline SHAM (S); SHAM + Liraglutide (0.06 mg/kg/day - SLL); SHAM + Liraglutide (0.6 mg/kg/day - SLH); saline OVX (O); OVX + Liraglutide (0.06 mg/kg/day - OLL); OVX + Liraglutide (0.6 mg/kg/day - OLH) groups and treated for 30 days. Systolic blood pressure (SBP) was verified using the tail plethysmography method. Fasting blood glucose was measured using a glucometer. The parameters of urinary volume excreted in the 24-hour period were monitored with the aid of a metabolic cage. In renal tissue, nitrite (NO2 - ) and nitrate (NO3 - ) analyzes were performed using the Griess method and oxidative stress was assessed by analyzing the content of advanced protein oxidation products (AOPP). Renal collagen deposition was determined using Picrosirius red staining. Lipase, creatinine and plasma urea were analyzed by the enzymatic kinetic method and urinary sodium by selective electrode. Liraglutide reduced body weight gain in the S groups but was not able to prevent the increase in O. Liraglutide only at high dose increased urinary excretion in both S and O. Independent of dose, liraglutide increased nitrate and reduced nitrite in the presence of OH, in O these alterations were not observed. AOPP were reduced in SLL and OLH. Urea and sodium increased in SLL and OLL and creatinine and urea in OLH. Effects were independent of blood pressure and glycemic control in liraglutide-treated animals. Liraglutide appears to have a differentiated action on the kidney of hypertensive females, depending on dose and hormonal status. Therefore, the use of this drug in relation to the dose and the clinical situation of the individual involved in the treatment must be considered.

Navegar

Navegando Mestrado em Ciências Fisiológicas por Autor "Andrade, Tadeu Uggere de"

Resultados por página

Opções de Ordenação