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1.
Neuroscience ; 401: 117-129, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30654003

RESUMO

Hepatic encephalopathy (HE) represents a brain dysfunction caused by both acute and chronic liver failures, and its severity deeply affects the prognosis of patients with impaired liver function. In its pathophysiology, ammonia levels and glutamatergic system hyperactivity seem to play a pivotal role in the disruption of brain homeostasis. Here, we investigate important outcomes involved in behavioral performance, electroencephalographic patterns, and neurochemical parameters to better characterize the well-accepted animal model of acute liver failure (ALF) induced by subtotal hepatectomy (92% removal of tissue) that produces ALF. This study was divided into three cohorts: (1) rats clinically monitored after hepatectomy every 6 h for 96 h or until death; (2) rats tested in an open-field task (OFT) before and after surgery and had blood, cerebrospinal fluid, and brain tissue collected after the last OFT; and (3) rats that had continuous EEGs recorded before and after surgery for 3 days. The hepatectomized rats presented significant motor behavioral changes accompanied by important abnormalities in classical blood laboratory parameters of ALF, and EEG features suggestive of HE and deep disturbances in the brain glutamatergic system. Using an animal model of ALF induced via subtotal hepatectomy, this work provides a comprehensive and reliable experimental model that increases the opportunity for studying the effects of new treatment strategies to be explored in an unprecedented way. It also presents insights into the pathophysiology of HE in a reproducible model of ALF, which correlates important neurochemical and EEG aspects of the syndrome.


Assuntos
Encéfalo/fisiopatologia , Comportamento Exploratório , Encefalopatia Hepática/fisiopatologia , Falência Hepática Aguda/fisiopatologia , Animais , Modelos Animais de Doenças , Eletroencefalografia , Hepatectomia , Encefalopatia Hepática/sangue , Falência Hepática Aguda/sangue , Masculino , Atividade Motora/fisiologia , Malformações do Sistema Nervoso , Ratos , Ratos Wistar
2.
Genet Mol Res ; 16(3)2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28973756

RESUMO

Geraniol is an acyclic monoterpene alcohol present in the essential oil of many aromatic plants and is one of the most frequently used molecules by the flavor and fragrance industries. The literature also reports its therapeutic potential, highlighting itself especially as a likely molecule for the development of drugs against cancer. In view of these considerations, this study was designed to evaluate the cytotoxic and genotoxic potential of geraniol, in an in vitro protocol, using two types of human cells: one without the ability to metabolize (peripheral blood mononuclear cells - PBMC), and the other with this capability (human hepatoma cell line - HepG2) through the comet assay and the micronucleus test. Four concentrations (10, 25, 50, and 100 µg/mL) were selected for the genotoxic assessment for PBMC and three (1.25, 2.5, and 5 µg/mL) for HepG2 cells based on cytotoxicity tests (MTT assay). Results showed that geraniol did not present genotoxic or clastogenic/aneugenic effects on both cell types under the conditions studied. However, caution is advised in the use of this substance by humans, since a significant reduction in viability of HepG2 and a marked decrease in cell viability on normal PBMC were verified.


Assuntos
Dano ao DNA , Monócitos/efeitos dos fármacos , Terpenos/toxicidade , Monoterpenos Acíclicos , Células Hep G2 , Humanos
3.
Mol Neurobiol ; 54(5): 3137-3148, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27052954

RESUMO

The nucleoside guanosine (GUO) increases glutamate uptake by astrocytes and acts as antioxidant, thereby providing neuroprotection against glutamatergic excitotoxicity, as we have recently demonstrated in an animal model of chronic hepatic encephalopathy. Here, we investigated the neuroprotective effect of GUO in an acute ammonia intoxication model. Adult male Wistar rats received an intraperitoneal (i.p.) injection of vehicle or GUO 60 mg/kg, followed 20 min later by an i.p. injection of vehicle or 550 mg/kg of ammonium acetate. Afterwards, animals were observed for 45 min, being evaluated as normal, coma (i.e., absence of corneal reflex), or death status. In a second cohort of rats, video-electroencephalogram (EEG) recordings were performed. In a third cohort of rats, the following were measured: (i) plasma levels of glucose, transaminases, and urea; (ii) cerebrospinal fluid (CSF) levels of ammonia, glutamine, glutamate, and alanine; (iii) glutamate uptake in brain slices; and (iv) brain redox status and glutamine synthetase activity in cerebral cortex. GUO drastically reduced the lethality rate and the duration of coma. Animals treated with GUO had improved EEG traces, decreased CSF levels of glutamate and alanine, lowered oxidative stress in the cerebral cortex, and increased glutamate uptake by astrocytes in brain slices compared with animals that received vehicle prior to ammonium acetate administration. This study provides new evidence on mechanisms of guanine-derived purines in their potential modulation of glutamatergic system, contributing to GUO neuroprotective effects in a rodent model of by acute ammonia intoxication.


Assuntos
Amônia/toxicidade , Guanosina/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Encéfalo/metabolismo , Coma/sangue , Coma/líquido cefalorraquidiano , Coma/induzido quimicamente , Coma/tratamento farmacológico , Modelos Animais de Doenças , Eletroencefalografia , Guanosina/uso terapêutico , Masculino , Fármacos Neuroprotetores/uso terapêutico , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar
4.
Food Chem Toxicol ; 53: 119-25, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23220610

RESUMO

The antioxidant effects of the hydro-alcoholic guaraná extract (Paullinia cupana var. sorbilis Mart.) on nitric oxide (NO) and other compounds generated from the degradation of sodium nitroprusside (SNP) in an embryonic fibroblast culture (NIH-3T3 cells) were evaluated. The guaraná bioactive compounds were initially determined by high-performance liquid chromatography: caffeine=12.240 mg/g, theobromine=6.733 mg/g and total catechins=4.336 mg/g. Cells were exposed to 10 µM SNP during a 6 h period because the cells exhibited >90% mortality at this concentration. Guaraná was added to the cultures in five concentrations (0.5, 1, 5, 10 and 20 mg/mL). The guaraná antioxidant effect was evaluated by viability assays, biochemical oxidation [lipid peroxidation, catalase and superoxide dismutase (SOD) activity] and genotoxicity (DNA Comet assay) analysis. Additionally, oxidative stress was evaluated by a 2,7-dihydrodichlorofluorescein diacetate fluorescence assay. Guaraná reverted the SNP toxicity mainly at lower concentrations (<5 mg), which decreased cell mortality, lipid peroxidation, DNA damage and cell oxidative stress as well as increased the SOD levels. These results demonstrate that guaraná has an antioxidant effect on NO metabolism in situations with higher cellular NO levels.


Assuntos
Fibroblastos/efeitos dos fármacos , Nitroprussiato/efeitos adversos , Paullinia/química , Extratos Vegetais/farmacologia , Animais , Antioxidantes/farmacologia , Cafeína/análise , Cafeína/farmacologia , Catequina/análise , Catequina/farmacologia , Cromatografia Líquida de Alta Pressão , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Fibroblastos/citologia , Fluoresceínas/análise , Camundongos , Células NIH 3T3 , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Teobromina/análise , Teobromina/farmacologia
5.
Braz J Biol ; 70(3): 677-84, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20730357

RESUMO

Among the phytophagous insects which attack crops, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera, Noctuidae) is particularly harmful in the initial growth phase of rice plants. As a potential means of controlling this pest, and considering that the entomopathogen Bacillus thuringiensis Berliner demonstrates toxicity due to synthesis of the Cry protein, the present study was undertaken to evaluate this toxic effect of B. thuringiensis thuringiensis 407 (pH 408) and B. thuringiensis kurstaki HD-73 on S. frugiperda. The following method was used. Both bacterial strains were evaluated in vitro in 1st instar S. frugiperda caterpillars, by means of histopathological assays. The Cry1Ab and Cry1Ac proteins, codified by the respective strains of B. thuringiensis, were evaluated in vivo by bioassays of 1st instar S. frugiperda caterpillars in order to determine the Mean Lethal Concentration (LC50). The results of the histopathological analysis of the midget of S. frugiperda caterpillars demonstrate that treatment with the B. thuringiensis thuringiensis strain was more efficient, because the degradations of the microvilosities started 9 hours after treatment application (HAT), while in the B. thuringiensis kurstaki the same effect was noticed only after 12 HAT. Toxicity data of the Cry1Ab and Cry1Ac proteins presented for the target-species LC50 levels of 9.29 and 1.79 microgxcm-2 respectively. The strains and proteins synthesised by B. thuringiensis thuringiensis and B. thuringiensis kurstaki are effective in controlling S. frugiperda, and may be used to produce new biopesticides or the genes may be utilised in the genetic transformation of Oryza sativa L.


Assuntos
Bacillus thuringiensis/química , Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade , Spodoptera/efeitos dos fármacos , Animais , Bacillus thuringiensis/classificação , Toxinas de Bacillus thuringiensis , Dose Letal Mediana , Controle Biológico de Vetores
6.
Braz. j. biol ; Braz. j. biol;70(3): 677-684, Aug. 2010. tab
Artigo em Inglês | LILACS | ID: lil-555282

RESUMO

Among the phytophagous insects which attack crops, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera, Noctuidae) is particularly harmful in the initial growth phase of rice plants. As a potential means of controlling this pest, and considering that the entomopathogen Bacillus thuringiensis Berliner demonstrates toxicity due to synthesis of the Cry protein, the present study was undertaken to evaluate this toxic effect of B. thuringiensis thuringiensis 407 (pH 408) and B. thuringiensis kurstaki HD-73 on S. frugiperda. The following method was used. Both bacterial strains were evaluated in vitro in 1st instar S. frugiperda caterpillars, by means of histopathological assays. The Cry1Ab and Cry1Ac proteins, codified by the respective strains of B. thuringiensis, were evaluated in vivo by bioassays of 1st instar S. frugiperda caterpillars in order to determine the Mean Lethal Concentration (LC50). The results of the histopathological analysis of the midget of S. frugiperda caterpillars demonstrate that treatment with the B. thuringiensis thuringiensis strain was more efficient, because the degradations of the microvilosities started 9 hours after treatment application (HAT), while in the B. thuringiensis kurstaki the same effect was noticed only after 12 HAT. Toxicity data of the Cry1Ab and Cry1Ac proteins presented for the target-species LC50 levels of 9.29 and 1.79 μg.cm-2 respectively. The strains and proteins synthesised by B. thuringiensis thuringiensis and B. thuringiensis kurstaki are effective in controlling S. frugiperda, and may be used to produce new biopesticides or the genes may be utilised in the genetic transformation of Oryza sativa L.


Entre os insetos fitófagos que atacam as culturas, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera, Noctuidae) destaca-se como uma praga polífaga que causa prejuízos na fase inicial da cultura do arroz. No seu controle, o entomopatógeno Bacillus thuringiensis Berliner revela-se tóxico devido à síntese de proteínas Cry. Nesse contexto, o objetivo deste trabalho foi avaliar a toxicidade das cepas e proteínas Cry de B. thuringiensis thuringiensis 407 (pH 408) e B. thuringiensis kurstaki HD-73 sobre S. frugiperda. As duas cepas bacterianas foram avaliadas, in vitro, em lagartas de 1º instar de S. frugiperda, através de ensaios de histopatologia. As proteínas Cry1Ab e Cry1Ac, codificadas pelas respectivas cepas de B. thuringiensis, foram avaliadas in vivo, através de bioensaios com lagartas de 1º instar de S. frugiperda para determinação da Concentração Letal Média (CL50). Os resultados da análise histopatológica do intestino médio das lagartas S. frugiperda mostram que o tratamento com a cepa B. thuringiensis thuringiensis foi mais eficiente e a degradação das microvilosidade iniciou-se 9 horas após a aplicação dos tratamentos (HAT). Para B. thuringiensis kurstaki, o mesmo efeito foi observado, 12 HAT. Os dados de toxicidade das proteínas de Cry1Ab e Cry1Ac revelaram para a espécie-alvo uma CL50 de 9,29 e 1,79 μg.cm-2, respectivamente. As cepas e proteínas sintetizadas por B. thuringiensis thuringiensis e B. thuringiensis kurstaki são eficientes no controle de S. frugiperda, e poderão ser usadas na produção de novos biopesticidas ou a utilização dos genes na transformação genética de Oryza sativa L.


Assuntos
Animais , Bacillus thuringiensis/química , Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade , Spodoptera/efeitos dos fármacos , Bacillus thuringiensis/classificação , Controle Biológico de Vetores
7.
Braz. J. Biol. ; 70(3): 677-684, Aug. 2010. tab
Artigo em Inglês | VETINDEX | ID: vti-2587

RESUMO

Among the phytophagous insects which attack crops, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera, Noctuidae) is particularly harmful in the initial growth phase of rice plants. As a potential means of controlling this pest, and considering that the entomopathogen Bacillus thuringiensis Berliner demonstrates toxicity due to synthesis of the Cry protein, the present study was undertaken to evaluate this toxic effect of B. thuringiensis thuringiensis 407 (pH 408) and B. thuringiensis kurstaki HD-73 on S. frugiperda. The following method was used. Both bacterial strains were evaluated in vitro in 1st instar S. frugiperda caterpillars, by means of histopathological assays. The Cry1Ab and Cry1Ac proteins, codified by the respective strains of B. thuringiensis, were evaluated in vivo by bioassays of 1st instar S. frugiperda caterpillars in order to determine the Mean Lethal Concentration (LC50). The results of the histopathological analysis of the midget of S. frugiperda caterpillars demonstrate that treatment with the B. thuringiensis thuringiensis strain was more efficient, because the degradations of the microvilosities started 9 hours after treatment application (HAT), while in the B. thuringiensis kurstaki the same effect was noticed only after 12 HAT. Toxicity data of the Cry1Ab and Cry1Ac proteins presented for the target-species LC50 levels of 9.29 and 1.79 μg.cm-2 respectively. The strains and proteins synthesised by B. thuringiensis thuringiensis and B. thuringiensis kurstaki are effective in controlling S. frugiperda, and may be used to produce new biopesticides or the genes may be utilised in the genetic transformation of Oryza sativa L.(AU)


Entre os insetos fitófagos que atacam as culturas, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera, Noctuidae) destaca-se como uma praga polífaga que causa prejuízos na fase inicial da cultura do arroz. No seu controle, o entomopatógeno Bacillus thuringiensis Berliner revela-se tóxico devido à síntese de proteínas Cry. Nesse contexto, o objetivo deste trabalho foi avaliar a toxicidade das cepas e proteínas Cry de B. thuringiensis thuringiensis 407 (pH 408) e B. thuringiensis kurstaki HD-73 sobre S. frugiperda. As duas cepas bacterianas foram avaliadas, in vitro, em lagartas de 1º instar de S. frugiperda, através de ensaios de histopatologia. As proteínas Cry1Ab e Cry1Ac, codificadas pelas respectivas cepas de B. thuringiensis, foram avaliadas in vivo, através de bioensaios com lagartas de 1º instar de S. frugiperda para determinação da Concentração Letal Média (CL50). Os resultados da análise histopatológica do intestino médio das lagartas S. frugiperda mostram que o tratamento com a cepa B. thuringiensis thuringiensis foi mais eficiente e a degradação das microvilosidade iniciou-se 9 horas após a aplicação dos tratamentos (HAT). Para B. thuringiensis kurstaki, o mesmo efeito foi observado, 12 HAT. Os dados de toxicidade das proteínas de Cry1Ab e Cry1Ac revelaram para a espécie-alvo uma CL50 de 9,29 e 1,79 μg.cm-2, respectivamente. As cepas e proteínas sintetizadas por B. thuringiensis thuringiensis e B. thuringiensis kurstaki são eficientes no controle de S. frugiperda, e poderão ser usadas na produção de novos biopesticidas ou a utilização dos genes na transformação genética de Oryza sativa L.(AU)


Assuntos
Animais , Lepidópteros/imunologia , Bacillus thuringiensis/patogenicidade , Spodoptera , Bioensaio , Praguicidas/efeitos adversos , Uso de Praguicidas
8.
Mol Cell Endocrinol ; 314(1): 84-9, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19666082

RESUMO

It now appears that obesity is associated with a low-grade inflammation of white adipose tissue resulting from chronic activation of the innate immune system as interleukin-1 beta (IL-1). Previous investigations have described a positive association between IL-1 beta +3953 (C>T) gene polymorphism (rs 1143634) and obesity, suggesting functional effects on fat mass, fat metabolism and body mass. However, it is necessary to determine if these results occur in other populations and if they are influenced by sex and age. Therefore, we performed a case-control study using 880 Caucasian subjects (59.7+/-11.9 years old) from the Brazilian Aging Research Program (non-overweight=283, overweight=334, obese=263) previously investigated in genetic studies, in whom we analyzed the IL-1 beta +3953C/T polymorphism. We observed higher T allele (CT/TT) frequency in non-overweight than overweight and obese groups. The odds ratio showed 1.340 (95% CI: 1.119-1.605) times more chance of the obese group being CC carriers compared to non-overweight group independent of sex and age. This study corroborates the idea that the IL-1 system is linked to the development of obesity.


Assuntos
Interleucina-1beta/genética , Obesidade/fisiopatologia , Polimorfismo de Nucleotídeo Único , Tecido Adiposo/metabolismo , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Brasil , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Interleucina-1beta/metabolismo , Masculino , Pessoa de Meia-Idade , Razão de Chances , Adulto Jovem
9.
J Hypertens ; 16(12 Pt 1): 1797-804, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9869014

RESUMO

OBJECTIVE: Previous studies have shown that angiotensin-(1-7) potentiates the vascular actions of bradykinin. In the present study, we evaluated the interaction of bradykinin and angiotensin-(1-7) in the central modulation of baroreflex control of the heart rate. MATERIALS AND METHODS: Blood pressure and reflex bradycardia, elicited by intravenous injection of phenylephrine, were evaluated in conscious male Wistar rats before and at the end of 1 h of an intracerebroventricular infusion of angiotensin-(1-7) at 0.5 or 1.0 microg/h combined with bradykinin at 2.5 microg/h; or angiotensin-(1-7) at 2.0 microg/h combined with bradykinin at 4.0 microg/h; or angiotensin-(1-7) alone at 2.0 or 4.0 microg/h; or bradykinin alone at 4.0 or 8.0 microg/h; or saline at 8 microl/h. In addition, baroreflex bradycardia was evaluated before and at the end of 1 and 2 h of intracerebroventricular infusion of angiotensin-(1-7) at 4 microg/h for 2 h; or saline at 8 microl/h in the first hour followed by HOE 140 at 90 ng/h in the second hour; or angiotensin-(1-7) at 4 microg/h in the first hour followed by angiotensin-(1-7) at 4 microg combined with HOE 140 at 90 ng/h in the second hour; or HOE 140 at 90 ng/h in the first hour followed by HOE 140 at 90th ng/h combined with angiotensin-(1-7) at 4 microg/h in the second hour; or saline at 8 microl/h for 2 h. RESULTS: The intracerebroventricular infusion of angiotensin-(1-7) or bradykinin alone required a dose of 4.0 and 8.0 microg/h, respectively, to facilitate baroreflex control of the heart. However, a simultaneous infusion of these peptides at subeffective rates was able to produce a significant increase in baroreflex sensitivity. In addition, the facilitation of the baroreflex control of the heart rate induced by angiotensin-(1-7) at 4.0 microg/h was inhibited by HOE 140. CONCLUSIONS: These results suggest that centrally, bradykinin and angiotensin-(1-7) can interact in order to modulate baroreflex control of the heart rate. In addition, our data indicate that the central modulatory effect of angiotensin-(1-7) on the baroreflex is mediated, at least in part, by the release of kinins.


Assuntos
Angiotensina II/farmacologia , Barorreflexo/efeitos dos fármacos , Bradicinina/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Antagonistas Adrenérgicos beta , Angiotensina I , Angiotensina II/administração & dosagem , Angiotensina II/antagonistas & inibidores , Animais , Barorreflexo/fisiologia , Bradicinina/administração & dosagem , Bradicinina/análogos & derivados , Bradicinina/metabolismo , Antagonistas dos Receptores da Bradicinina , Sinergismo Farmacológico , Frequência Cardíaca/fisiologia , Injeções Intraventriculares , Masculino , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/antagonistas & inibidores , Ratos , Ratos Wistar
10.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);50(6): 685-90, dez. 1998. ilus, tab, graf
Artigo em Português | LILACS | ID: lil-265544

RESUMO

Quatro grupos de eqüinos da raça Brasileiro de Hipismo foram submetidos a jejuns de 24 e 48 horas com a finalidade de se estudar a capacidade de absorçäo do intestino delgado. Dois grupos foram alimentados unicamente com capim coast cross (Cynodon dactylon). Os outros dois grupos, além de pasto de coast cross, receberam suplementaçäo com gräos. Ao final dos períodos de jejum, os animais receberam 1g de glucose/kg de peso corporal, em soluçäo a 20 por cento, por sonda nasogástrica. Amostras de sangue foram colhidas imediatamente antes, 30, 60, 120, 180, 240, 300 e 360 minutos após a administraçäo de glicose, para determinaçäo da glicemia pelo método da ortotoluidina e da insulina, pelo uso do radioimunoensaio. Os animais que receberam alimento concentrado apresentaram maiores aumentos na glicemia e na insulinemia que aqueles mantidos apenas em regime de pasto. O período de jejum de 48 horas induziu concentraçöes mais elevadas de glicemia e de insulinemia que o jejum de 24 horas


Assuntos
Animais , Feminino , Masculino , Glicosídeos , Cavalos , Insulina
11.
Rev Bras Enferm ; 51(3): 523-8, 1998.
Artigo em Português | MEDLINE | ID: mdl-10776292

RESUMO

The purpose of this work was to bring back some historical aspects of the Federal University of Minas Gerais Nursing School--EEUFMG, since its creation in 1933 until 1998.


Assuntos
Escolas de Enfermagem/história , Universidades/história , Brasil , Bacharelado em Enfermagem/história , Educação de Pós-Graduação em Enfermagem/história , História do Século XX , Humanos
12.
Hypertension ; 27(6): 1284-90, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8641737

RESUMO

We have recently shown that an angiotensin-(1-7) [Ang-(I-7)] analogue, D-Ala7-Ang-(1-7) (A-779), is a selective Ang-(1-7) antagonist with no significant action on angiotensin type 1 or type 2 receptors. The availability of selective angiotensin antagonists prompted us to evaluate the role of Ang-(1-7) and Ang II on central modulation of the baroreflex control of heart rate in normotensive Wistar rats and spontaneously hypertensive rats (SHR). Blood pressure recording and reflex changes in heart rate elicited by intravenous bolus injections of phenylephrine were made before and within 1 and 3 hours of intracerebroventricular (ICV, lateral ventricle) infusion of saline (8 microL/h), A-779 (4 microg/h), DuP 753 (100 microg/h), or CGP 42112A (50 mu g/h) in conscious rats. The slope of the relationship between changes in pulse interval versus changes in mean arterial pressure was used as an index of the baroreflex control of heart rate. ICV infusion of saline or any of the antagonists did not significantly change basal levels of mean arterial pressure and heart rate in SHR (170 +/- 6 mm Hg nd 360 +/- 9 beats per minute, respectively; n = 29) or Wistar rats (108 +/- 2 mm Hg and 377 +/- 6 beats per minute, respectively; n=29). Three hours of ICV infusion of A-779 markedly decreased baroreflex sensitivity in Wistar rats (from a basal slope of 1.09 +/- O.3). In contrast, A-779 did not significantly alter the depressed baroreflex sensitivity of SHR (0.61 +/- O.l). ICV infusion of DuP 753 produced a significant increase (60 percent) in baroreflex control of heart rate in both Wistar rats and SHR. Saline or CGP 42112A infusions did not significantly alter baroreflex control of heart rate. These results suggest that endogenous Ang II and Ang-(1-7) are differentially affecting central baroreflex modulation, acting probably through distinct receptor subtypes. Although the central Ang II inhibitory effect is mediated by the type 1 receptor subtype, the facilitatory effect of Ang-(1-7) might be mediated by a different, unidentified receptor.


Assuntos
Angiotensina II/antagonistas & inibidores , Anti-Hipertensivos/farmacologia , Barorreflexo/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Angiotensina II/análogos & derivados , Angiotensina II/farmacologia , Animais , Compostos de Bifenilo/farmacologia , Imidazóis/farmacologia , Losartan , Masculino , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Tetrazóis/farmacologia
13.
Rev Bras Enferm ; 48(1): 7-16, 1995.
Artigo em Português | MEDLINE | ID: mdl-8715677

RESUMO

This a phenomenologial study rites in the memory of elderly people, originated from the discomfort lived by the authors in their professional life dealing with death and dying. Verbal information from elderly people was collected with the objective of recovery and decoding mortuary rites. Nine themes originated from these informations: feelings and meanings in relation to death, the time of death, the annunciation death, the body's preparations, the watcher, the funeral procession, the grave, the return to home, the remembered death. The results gave the authors opportunity to understand better the attitudes of health professionals in caring for patients and their families in this existential experience of to-be-for-death. The death rationalized by scientific knowledge and nonpersonal technological care hides new rites, transmuted by new representations which the society built.


Assuntos
Idoso/psicologia , Atitude do Pessoal de Saúde , Atitude Frente a Morte , Rituais Fúnebres , Adaptação Psicológica , Existencialismo , Humanos , Pesquisa Metodológica em Enfermagem
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