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Borgo MV, Claudio ERG, Silva FB, Romero WG, Gouvea SA, Moysés MR, Santos RL, Almeida SA, Podratz PL, Graceli JB, Abreu GR. Hormonal therapy with estradiol and drospirenone improves endothelium-dependent vasodilation in the coronary bed of ovariectomized spontaneously hypertensive rats. ACTA ACUST UNITED AC 2016; 49:e4655. [PMID: 26577845 PMCID: PMC4678653 DOI: 10.1590/1414-431x20154655] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 06/29/2015] [Indexed: 02/07/2023]
Abstract
Drospirenone (DRSP) is a progestin with anti-aldosterone properties and it reduces
blood pressure in hypertensive women. However, the effects of DRSP on
endothelium-dependent coronary vasodilation have not been evaluated. This study
investigated the effects of combined therapy with estrogen (E2) and DRSP on
endothelium-dependent vasodilation of the coronary bed of ovariectomized (OVX)
spontaneously hypertensive rats. Female spontaneously hypertensive rats (n=87) at 12
weeks of age were randomly divided into sham operated (Sham), OVX, OVX treated with
E2 (E2), and OVX treated with E2 and DRSP (E2+DRSP) groups. Hemodynamic parameters
were directly evaluated by catheter insertion into the femoral artery.
Endothelium-dependent vasodilation in response to bradykinin in the coronary arterial
bed was assessed using isolated hearts according to a modified Langendorff method.
Coronary protein expression of endothelial nitric oxide synthase and estrogen
receptor alpha (ER-α) was assessed by Western blotting. Histological slices of
coronary arteries were stained with hematoxylin and eosin, and morphometric
parameters were analyzed. Oxidative stress was assessed in situ by
dihydroethidium fluorescence. Ovariectomy increased systolic blood pressure, which
was only prevented by E2+DRSP treatment. Estrogen deficiency caused endothelial
dysfunction, which was prevented by both treatments. However, the vasodilator
response in the E2+DRSP group was significantly higher at the three highest
concentrations compared with the OVX group. Reduced ER-α expression in OVX rats was
restored by both treatments. Morphometric parameters and oxidative stress were
augmented by OVX and reduced by E2 and E2+DRSP treatments. Hormonal therapy with E2
and DRSP may be an important therapeutic option in the prevention of coronary heart
disease in hypertensive post-menopausal women.
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Affiliation(s)
- M V Borgo
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
| | - E R G Claudio
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
| | - F B Silva
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
| | - W G Romero
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
| | - S A Gouvea
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
| | - M R Moysés
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
| | - R L Santos
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
| | - S A Almeida
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
| | - P L Podratz
- Departamento de Morfologia, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
| | - J B Graceli
- Departamento de Morfologia, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
| | - G R Abreu
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES, Brasil
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Santos RL, Lima JT, Rouver WN, Moysés MR. Deficiency of sex hormones does not affect 17-ß-estradiol-induced coronary vasodilation in the isolated rat heart. ACTA ACUST UNITED AC 2016; 49:e5058. [PMID: 27074167 PMCID: PMC4833220 DOI: 10.1590/1414-431x20165058] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 02/04/2016] [Indexed: 11/22/2022]
Abstract
The relaxation of coronary arteries by estrogens in the coronary vascular beds of
naive and hypertensive rats has been well described. However, little is known about
this action in gonadectomized rats. We investigated the effect of 17-ß-estradiol (E2)
in coronary arteries from gonadectomized rats, as well as the contributions of
endothelium-derived factors and potassium channels. Eight-week-old female and male
Wistar rats weighing 220-300 g were divided into sham-operated and gonadectomized
groups (n=9−12 animals per group). The baseline coronary perfusion pressure (CPP) was
determined, and the vasoactive effects of 10 μM E2 were assessed by bolus
administration before and after endothelium denudation or by perfusion with
NG-nitro-L-arginine methyl ester (L-NAME), indomethacin, clotrimazole,
L-NAME plus indomethacin, L-NAME plus clotrimazole or tetraethylammonium (TEA). The
CPP differed significantly between the female and sham-operated male animals.
Gonadectomy reduced the CPP only in female rats. Differences in E2-induced relaxation
were observed between the female and male animals, but male castration did not alter
this response. For both sexes, the relaxation response to E2 was, at least partly,
endothelium-dependent. The response to E2 was reduced only in the sham-operated
female rats treated with L-NAME. However, in the presence of indomethacin,
clotrimazole, L-NAME plus indomethacin or L-NAME plus clotrimazole, or TEA, the E2
response was significantly reduced in all groups. These results highlight the
importance of prostacyclin, endothelium-derived hyperpolarizing factor, and potassium
channels in the relaxation response of coronary arteries to E2 in all groups, whereas
nitric oxide may have had an important role only in the sham-operated female
group.
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Affiliation(s)
- R L Santos
- Departamento de Ciências Fisiológicas Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
| | - J T Lima
- Departamento de Ciências Fisiológicas Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
| | - W N Rouver
- Departamento de Ciências Fisiológicas Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
| | - M R Moysés
- Departamento de Ciências Fisiológicas Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
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3
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Lino JR, Ramos-Jorge J, Coelho VS, Ramos-Jorge ML, Moysés MR, Ribeiro JCR. Association and comparison between visual inspection and bitewing radiography for the detection of recurrent dental caries under restorations. Int Dent J 2015; 65:178-81. [PMID: 26032493 DOI: 10.1111/idj.12172] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
PURPOSE The aim of the present study was to investigate, in posterior teeth, the association between the characteristics of the margins of a restoration visually inspected and the presence, under restorations, of recurrent or residual dental caries detected by radiographic examination. Furthermore, the agreement between visual inspection and radiographs to detect dental caries was assessed. METHODS Eighty-five permanent molars and premolars with resin restorations on the interproximal and/or occlusal faces, from 18 patients, were submitted for visual inspection and radiographic examination. The visual inspection involved the criteria of the International Caries Detection and Assessment System (ICDAS). Bitewing radiographs were used for the radiographic examination. Logistic regression was used to analyse the association between the characteristics of the margins of a restoration assessed by visual inspection (absence of dental caries, or early, established, inactive and active lesions) and the presence of recurrent caries detected by radiographs. Kappa coefficients were calculated for determining agreement between the two methods. RESULTS The Kappa coefficient for agreement between visual inspection and radiographic examination was 0.19. Established lesions [odds ratio (OR) = 9.89; 95% confidence interval (95% CI): 2.94-33.25; P < 0.05] and lesion activity (OR = 2.57; 95% CI: 0.91-7.27; P < 0.05) detected by visual inspection, were associated with recurrent or residual dental caries detected by radiographs. Restorations with established and active lesions at the margins had a greater chance of exhibiting recurrent or residual lesions in the radiographic examination. CLINICAL SIGNIFICANCE The present findings demonstrate that restorations with established and active lesions at the margins when visually inspected often require removal and retreatment.
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Affiliation(s)
- José R Lino
- Universidade Vale do Rio Verde, Três Corações, Brazil
| | - Joana Ramos-Jorge
- Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Brazil
| | | | - Maria L Ramos-Jorge
- Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Brazil
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Graceli JB, Cicilini MA, Bissoli NS, Abreu GR, Moysés MR. Roles of estrogen and progesterone in modulating renal nerve function in the rat kidney. Braz J Med Biol Res 2013; 46:521-7. [PMID: 23828583 PMCID: PMC3854445 DOI: 10.1590/1414-431x20132666] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 03/20/2013] [Indexed: 11/21/2022] Open
Abstract
The maintenance of extracellular Na+ and Cl- concentrations
in mammals depends, at least in part, on renal function. It has been shown that
neural and endocrine mechanisms regulate extracellular fluid volume and
transport of electrolytes along nephrons. Studies of sex hormones and renal
nerves suggested that sex hormones modulate renal function, although this
relationship is not well understood in the kidney. To better understand the role
of these hormones on the effects that renal nerves have on Na+ and
Cl- reabsorption, we studied the effects of renal denervation and
oophorectomy in female rats. Oophorectomized (OVX) rats received 17β-estradiol
benzoate (OVE, 2.0 mg·kg-1·day-1, sc) and
progesterone (OVP, 1.7 mg·kg-1·day-1,
sc). We assessed Na+ and Cl- fractional
excretion (FENa+ and FECl-, respectively) and renal and plasma catecholamine release concentrations.
FENa+, FECl-, water intake, urinary flow, and renal and plasma catecholamine release
levels increased in OVX vs control rats. These effects were
reversed by 17β-estradiol benzoate but not by progesterone. Renal denervation
did not alter FENa+, FECl-, water intake, or urinary flow values vs controls.
However, the renal catecholamine release level was decreased in the OVP
(236.6±36.1 ng/g) and denervated rat groups (D: 102.1±15.7; ODE: 108.7±23.2;
ODP: 101.1±22.1 ng/g). Furthermore, combining OVX + D (OD: 111.9±25.4) decreased
renal catecholamine release levels compared to either treatment alone. OVE
normalized and OVP reduced renal catecholamine release levels, and the effects
on plasma catecholamine release levels were reversed by ODE and ODP replacement
in OD. These data suggest that progesterone may influence catecholamine release
levels by renal innervation and that there are complex interactions among renal
nerves, estrogen, and progesterone in the modulation of renal function.
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Affiliation(s)
- J B Graceli
- Departamento de Morfologia, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
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Dalpiaz PLM, Lamas AZ, Caliman IF, Medeiros ARS, Abreu GR, Moysés MR, Andrade TU, Alves MF, Carmona AK, Bissoli NS. The chronic blockade of angiotensin I-converting enzyme eliminates the sex differences of serum cytokine levels of spontaneously hypertensive rats. Braz J Med Biol Res 2013; 46:171-7. [PMID: 23369979 PMCID: PMC3854361 DOI: 10.1590/1414-431x20122472] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Accepted: 10/18/2012] [Indexed: 11/22/2022] Open
Abstract
Sex hormones modulate the action of both cytokines and the renin-angiotensin system. However, the effects of angiotensin I-converting enzyme (ACE) on the proinflammatory and anti-inflammatory cytokine levels in male and female spontaneously hypertensive rats (SHR) are unclear. We determined the relationship between ACE activity, cytokine levels and sex differences in SHR. Female (F) and male (M) SHR were divided into 4 experimental groups each (n = 7): sham + vehicle (SV), sham + enalapril (10 mg/kg body weight by gavage), castrated + vehicle, and castrated + enalapril. Treatment began 21 days after castration and continued for 30 days. Serum cytokine levels (ELISA) and ACE activity (fluorimetry) were measured. Male rats exhibited a higher serum ACE activity than female rats. Castration reduced serum ACE in males but did not affect it in females. Enalapril reduced serum ACE in all groups. IL-10 (FSV = 16.4 ± 1.1 pg/mL; MSV = 12.8 ± 1.2 pg/mL), TNF-α (FSV = 16.6 ± 1.2 pg/mL; MSV = 12.8 ± 1 pg/mL) and IL-6 (FSV = 10.3 ± 0.2 pg/mL; MSV = 7.2 ± 0.2 pg/mL) levels were higher in females than in males. Ovariectomy reduced all cytokine levels and orchiectomy reduced IL-6 but increased IL-10 concentrations in males. Castration eliminated the differences in all inflammatory cytokine levels (IL-6 and TNF-α) between males and females. Enalapril increased IL-10 in all groups and reduced IL-6 in SV rats. In conclusion, serum ACE inhibition by enalapril eliminated the sexual dimorphisms of cytokine levels in SV animals, which suggests that enalapril exerts systemic anti-inflammatory and anti-hypertensive effects.
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Affiliation(s)
- P L M Dalpiaz
- Universidade Federal do Espírito Santo, Departamento de Ciências Fisiológicas, Vitória, ES, Brasil
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6
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Santos RL, Marin EB, Gonçalves WLS, Bissoli NS, Abreu GR, Moysés MR. Sex differences in the coronary vasodilation induced by 17 β-oestradiol in the isolated perfused heart from spontaneously hypertensive rats. Acta Physiol (Oxf) 2010; 200:203-10. [PMID: 20426771 DOI: 10.1111/j.1748-1716.2010.02140.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
AIM The relaxation induced by oestrogen in the coronary vascular bed from normotensive rats has been well described. However, almost nothing is known about this action in spontaneously hypertensive rats (SHR). We investigated the effect of 17 β-oestradiol (E(2) ) in coronary arteries from SHR as well as the contribution of the endothelium and the vascular smooth muscle to this action. METHODS Coronary arteries from male and female rats were used. Mean arterial pressure (MAP) and baseline coronary perfusion pressure (CPP) were determined. The effects of 10 μm E(2) were assessed by in bolus administration before and after endothelium denudation (0.25 μm sodium deoxycholate) or perfusion with 100 μm N(ω)-nitro-L-arginine methyl ester (L-NAME), 2.8 μm indomethacin, 0.75 μm clotrimazole, 100 μm L-NAME after endothelium denudation (0.25 μm sodium deoxycholate), 100 μm L-NAME plus 2.8 μm indomethacin, 0.75 μm clotrimazole plus 2.8 μm indomethacin and 4 mm tetraethylammonium (TEA). RESULTS MAP was higher in the male group, while CPP was higher in the female group (P<0.05). There were no differences in E(2)-induced relaxation between females and males (-17±1.6 vs. -17±2% respectively). Only in the female group the E(2) response was significantly attenuated after endothelium removal or perfusion with clotrimazole. The response to E(2) was reduced in both groups with L-NAME, L-NAME plus indomethacin, L-NAME after endothelium removal or TEA. CONCLUSIONS Nitric oxide, endothelium-derived hyperpolarizing factor and potassium channels may have the most important role to E(2) response in the female group, whereas nitric oxide and potassium channels may have the most important role in the male group.
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MESH Headings
- Animals
- Biological Factors/metabolism
- Blood Pressure
- Coronary Vessels/drug effects
- Coronary Vessels/metabolism
- Coronary Vessels/physiopathology
- Cyclooxygenase Inhibitors/pharmacology
- Disease Models, Animal
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiopathology
- Enzyme Inhibitors/pharmacology
- Estradiol/metabolism
- Female
- Hypertension/metabolism
- Hypertension/physiopathology
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiopathology
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/antagonists & inhibitors
- Nitric Oxide Synthase/metabolism
- Perfusion
- Potassium Channel Blockers/pharmacology
- Potassium Channels/metabolism
- Rats
- Rats, Inbred SHR
- Sex Factors
- Vasodilation/drug effects
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Affiliation(s)
- R L Santos
- Department of Physiological Sciences, Biomedical Center, Federal University of Espírito Santo, Vitória, ES, Brazil
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Gonçalves WLS, Souza FM, Conti CL, Cirqueira JP, Rocha WA, Pires JGP, Barros LAP, Moysés MR. Influence of He-Ne laser therapy on the dynamics of wound healing in mice treated with anti-inflammatory drugs. Braz J Med Biol Res 2008; 40:877-84. [PMID: 17581688 DOI: 10.1590/s0100-879x2007000600018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Accepted: 03/07/2007] [Indexed: 12/13/2022] Open
Abstract
We determined the effects of helium-neon (He-Ne) laser irradiation on wound healing dynamics in mice treated with steroidal and non-steroidal anti-inflammatory agents. Male albino mice, 28-32 g, were randomized into 6 groups of 6 animals each: control (C), He-Ne laser (L), dexamethasone (D), D + L, celecoxib (X), and X + L. D and X were injected im at doses of 5 and 22 mg/kg, respectively, 24 h before the experiment. A 1-cm long surgical wound was made with a scalpel on the abdomens of the mice. Animals from groups L, D + L and X + L were exposed to 4 J (cm(2))-1 day-1 of He-Ne laser for 12 s and were sacrificed on days 1, 2, or 3 after the procedure, when skin samples were taken for histological examination. A significant increase of collagen synthesis was observed in group L compared with C (168 +/- 20 vs 63 +/- 8 mm(2)). The basal cellularity values on day 1 were: C = 763 +/- 47, L = 1116 +/- 85, D = 376 +/- 24, D + L = 698 +/- 31, X = 453 +/- 29, X + L = 639 +/- 32 U/mm(2). These data show that application of L increases while D and X decrease the inflammatory cellularity compared with C. They also show that L restores the diminished cellularity induced by the anti-inflammatory drugs. We suggest that He-Ne laser promotes collagen formation and restores the baseline cellularity after pharmacological inhibition, indicating new perspectives for laser therapy aiming to increase the healing process when anti-inflammatory drugs are used.
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Affiliation(s)
- W L S Gonçalves
- Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo
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8
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Gazolla CM, Ribeiro A, Moysés MR, Oliveira LAM, Pereira LJ, Sallum AW. Evaluation of the incidence of preterm low birth weight in patients undergoing periodontal therapy. J Periodontol 2007; 78:842-8. [PMID: 17470017 DOI: 10.1902/jop.2007.060295] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Preterm low birth weight was reported to be related to periodontal infections that might influence the fetus-placenta complex. The aim of this study was to provide periodontal treatment for pregnant women and to evaluate if this treatment can interfere with pregnancy duration and weight of the newborn. METHODS The sample consisted of 450 pregnant women who were under prenatal care at a polyclinic in Três Corações, Brazil. Women with risk factors, such as systemic alterations (ischemic cardiopathy, hypertension, tuberculosis, diabetes, cancer, anemia, seizure, psychopathology, urinary tract infection, sexually transmitted diseases, asthma, and human immunodeficiency virus), and/or users of alcohol, tobacco, and drugs were excluded from the study. Data related to age, socioeconomic level, race, marital status, number of previous pregnancies, and previous preterm delivery also were evaluated. Initially, the sample was divided into two groups: 122 healthy patients (group 1) and 328 patients with periodontal disease (group 2). In group 2, 266 patients underwent treatment and 62 patients dropped out. After mothers gave birth, pregnancy duration and the weight of all infants were analyzed and recorded. RESULTS There was no statistical difference between the healthy and treated groups. However, there was a difference in the non-treated group, with a 79% incidence of preterm low birth weight. Educational level, previous preterm birth, and periodontal disease were related significantly to preterm delivery (P <0.001). CONCLUSION Periodontal disease was related significantly to preterm low birth weight.
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Affiliation(s)
- Catia M Gazolla
- Clinical Dentistry Postgraduate Program, Vale do Rio Verde University, Três Corações, MG, Brazil.
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9
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Andrade TU, Pinto VD, Medeiros ARS, Abreu GR, Moysés MR, Sampaio KN, Bissoli NS. EFFECT OF ENALAPRIL TREATMENT ON THE SENSITIVITY OF CARDIOPULMONARY REFLEXES IN RATS WITH MYOCARDIAL INFARCTION. Clin Exp Pharmacol Physiol 2007; 34:606-11. [PMID: 17581216 DOI: 10.1111/j.1440-1681.2007.04613.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
1. The aim of the present study was to evaluate the effect of treatment with enalapril on the sensitivity of cardiopulmonary reflexes 30 days after myocardial infarction in Wistar rats. 2. Animals were divided into four groups: (i) sham operated, receiving vehicle (SHAM); (ii) infarcted, receiving vehicle (0.9% NaCl; INF); (iii) sham operated, receiving enalapril (SHAME); and (iv) infarcted, receiving enalapril (INFE). 3. Enalapril was administered at a dose of 10 mg/kg per day. Serotonin (4-32 microg/kg, i.v.) was administered in order to activate the Bezold-Jarisch reflex, which was estimated as the percentage of reduction in heart rate. 4. The volume-sensitive cardiopulmonary reflex was induced by saline overload and evaluated as the percentage increase in sodium and volume renal excretion. At the end of the experiments, rats were killed and hearts excised to estimate the size of the infarction. The weight of the kidneys, lungs, liver and cardiac chambers as ratios of bodyweight was used to estimate the extent of hypertrophy. 5. The results showed an impairment in the sensitivity of the cardiopulmonary reflexes in the INF group compared with the SHAM and SHAME groups. We observed right ventricle and pulmonary hypertrophy, a reduction in mean and systolic arterial pressure and an increase in heart rate in INF animals. In the INFE group, nearly all the parameters were normal compared with the INF group, except for systolic arterial pressure, which was only partially improved. 6. The main finding of the present study was that treatment with enalapril normalized the sensitivity of the cardiopulmonary reflexes, which could be due, in part, to the reduction of cardiac hypertrophy. The present study provides information about the beneficial effects of the angiotensin-converting enzyme inhibitors by normalizing the cardiopulmonary reflexes involved with the regulation of volume and sodium, as well as control of arterial pressure and heart rate in infarcted animals.
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Affiliation(s)
- T U Andrade
- Department of Pharmacy, University Centre of Vila Velha, Vila Velha, Brazil
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10
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Abstract
The present study was designed to determine relaxation in response to 17 beta-estradiol by isolated perfused hearts from intact normotensive male and female rats as well as the contribution of endothelium and its relaxing factors to this action. Baseline coronary perfusion pressure was determined and the vasoactive effects of 17 beta-estradiol (10 microM) were assessed by in bolus administration before and after endothelium denudation by infusion of 0.25 microM sodium deoxycholate or perfusion with 100 microM L-NAME, 2.8 microM indomethacin, 0.75 microM clotrimazole, 100 microM L-NAME plus 2.8 microM indomethacin, and 100 microM L-NAME plus 0.75 microM clotrimazole. Baseline coronary perfusion pressure differed significantly between males (84 +/- 2 mmHg, N = 61) and females (102 +/- 2 mmHg, N = 61). Bolus injection of 10 microM 17 beta-estradiol elicited a transient relaxing response in all groups, which was greater in coronary beds from females. For both sexes, the relaxing response to 17 beta-estradiol was at least in part endothelium-dependent. In the presence of the nitric oxide synthase inhibitor L-NAME, the relaxing response to 17 beta-estradiol was reduced only in females. Nevertheless, in the presence of indomethacin, a cyclooxygenase inhibitor, or clotrimazole, a cytochrome P450 inhibitor, the 17 beta-estradiol response was significantly reduced in both groups. In addition, combined treatment with L-NAME plus indomethacin or L-NAME plus clotrimazole also reduced the 17 beta-estradiol response in both groups. These results indicate the importance of prostacyclin and endothelium-derived hyperpolarizing factor in the relaxing response to 17 beta-estradiol. 17 beta-estradiol-induced relaxation may play an important role in the regulation of coronary tone and this may be one of the reasons why estrogen replacement therapy reduces the risk of coronary heart disease in postmenopausal women.
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Affiliation(s)
- R L Santos
- Departamento de Ciências Fisiológicas, Centro Biomédico, Universidade Federal do Espírito Santo, Victoria, ES, Brazil
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11
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Gouvêa SA, Moysés MR, Bissoli NS, Pires JGP, Cabral AM, Abreu GR. Oral administration of L-arginine decreases blood pressure and increases renal excretion of sodium and water in renovascular hypertensive rats. Braz J Med Biol Res 2003; 36:943-9. [PMID: 12845383 DOI: 10.1590/s0100-879x2003000700017] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The two-kidney, one-clip renovascular (2K1C) hypertension model is characterized by a reduction in renal flow on the clipped artery that activates the renin-angiotensin system. Endothelium dysfunction, including diminished nitric oxide production, is also believed to play a role in the pathophysiology of this model. Some studies have shown an effect of L-arginine (L-Arg, a nitric oxide precursor) on hypertension. In the present study we determined the ability of L-Arg (7 days of treatment) to reduce blood pressure and alter renal excretions of water, Na+ and K+ in a model of 2K1C-induced hypertension. Under ether anesthesia, male Wistar rats (150-170 g) had a silver clip (0.20 mm) placed around the left renal artery to produce the 2K1C renovascular hypertension model. In the experimental group, the drinking water was replaced with an L-Arg solution (10 mg/ml; average intake of 300 mg/day) from the 7th to the 14th day after surgery. Sham-operated rats were used as controls. At the end of the treatment period, mean blood pressure was measured in conscious animals. The animals were then killed and the kidneys were removed and weighed. There was a significant reduction of mean blood pressure in the L-Arg-treated group when compared to control (129 7 vs 168 6 mmHg, N = 8-10 per group; P<0.05). Concomitantly, a significant enhancement of water and Na+ excretion was observed in the 2K1C L-Arg-treated group when compared to control (water: 13.0 0.7 vs 9.2 0.5 ml/day, P<0.01; Na+: 1.1 0.05 vs 0.8 0.05 mEq/day, respectively, P<0.01). These results show that orally administered L-Arg acts on the kidney, possibly inducing changes in renal hemodynamics or tubular transport due to an increase in nitric oxide formation.
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Affiliation(s)
- S A Gouvêa
- Departamento de Ciências Fisiológicas, Centro Biomédico, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
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Abstract
The present study was designed to evaluate the differences in the coronary vasodilator actions of serotonin (5-HT) in isolated heart obtained from naive or castrated male and female rats that were treated with either estrogen or testosterone. Hearts from 12 groups of rats were used: male and female naive animals, castrated, castrated and treated with 17beta-estradiol (0.5 microg kg(-1) day(-1)) for 7 or 30 days, and castrated and treated with testosterone (0.5 mg kg(-1) day(-1)) for 7 or 30 days. After treatment, the vascular reactivity of the coronary bed was evaluated. Baseline coronary perfusion pressure (CPP) was determined and dose-response curves to 5-HT were generated. Baseline CPP differed between male (70 +/- 6 mmHg, N = 10) and female (115 +/- 6 mmHg, N = 12) naive rats. Maximal 5-HT-induced coronary vasodilation was higher (P<0.05) in naive female than in naive male rats. In both sexes, 5-HT produced endothelium-dependent coronary vasodilation. After castration, there was no significant difference in baseline CPP between hearts obtained from male and female rats (75 +/- 7 mmHg, N = 8, and 83 +/- 5 mmHg, N = 8, respectively). Castration reduced the 5-HT-induced maximal vasodilation in female and male rats (P<0.05). Estrogen treatment of castrated female rats restored (P<0.05) the vascular reactivity. In castrated male rats, 30 days of estrogen treatment increased (P<0.05) the responsiveness to 5-HT. The endothelium-dependent coronary vasodilator actions of 5-HT are greater in female rats and are modulated by estrogen. A knowledge of the mechanism of action of estrogen on coronary arteries could aid in the development of new therapeutic strategies and potentially decrease the incidence of cardiovascular disease in both sexes.
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Affiliation(s)
- M R Moysés
- Departamento de Ciências Fisiológicas, Centro Biomédico, Universidade Federal do Espírito Santo, Vitória, ES, Brasil.
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Abstract
Alterations in vascular alpha-adrenoceptor responsiveness following sinoaortic denervation was studied in conscious rats. The arterial hypertension observed in baroreceptor denervated rats decreased progressively during the 30 days of observation. A pressor hyperresponsiveness to methoxamine (10-80 micrograms/kg, iv), was observed 3 to 7 days after baroreceptor denervation followed by a gradual normalization of the vascular reactivity. The results indicate a possible participation of an enhanced alpha 1-adrenoceptor-mediated vasoconstrictor component in the early phase of neurogenic hypertension.
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Affiliation(s)
- M R Moysés
- Departamento de Ciencias Fisiológicas, Universidade Federal do Esprito Santo, Vitória, ES, Brasil
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Abstract
The influence of sex hormones on the development of left ventricular hypertrophy was investigated in baroreceptor-denervated rats. A significant increase (p less than 0.01) in the left ventricular weight/body weight ratio was observed in male but not in female rats 15 days after operation, compared to age- and sex-matched sham-operated rats. This differential hypertrophy occurred despite the development of a significant elevation in arterial blood pressure in both sexes. Castration prior to sinoaortic denervation did not change the level of arterial hypertension but caused a significant reduction (p less than 0.01) in left ventricular weight in male rats and a significant increase (p less than 0.01) in female rats. The pretreatment of male and female sinoaortic denervated and castrated rats with testosterone resulted in ventricular hypertrophy similar to that observed in intact male sinoaortic denervated rats. Pretreatment with estradiol, however, suppressed the left ventricular hypertrophy in intact male rats but did not change the normal ventricular mass observed in intact female sinoaortic denervated rats. These results indicate that the development of left ventricular hypertrophy in sinoaortic denervated rats is modulated by sex hormones, and that testosterone exerts a facilitatory and estradiol an inhibitory action.
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Affiliation(s)
- A M Cabral
- Department of Physiological Sciences, Federal University of Espirito Santo, Vitória, Brazil
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Vasquez EC, Cabral AM, Moysés MR, Mill JG. [Experimental models of the use of calcium antagonists in arterial hypertension]. Arq Bras Cardiol 1986; 46:245-50. [PMID: 3827668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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16
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Vasques EC, Mill JG, Moysés MR, da Silva FD, da Costa MB, Caldas JG, Cabral ADM, Vassalo DV. [Effects of verapamil on arterial blood pressure and heart rate in awake animals with neurogenic and renal hypertension]. Arq Bras Cardiol 1982; 39:99-103. [PMID: 7171334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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