RESUMO
Envenomation by the South American opisthoglyphous snake Philodryas olfersii causes local pain, edema, erythema and ecchymosis; systemic envenomation is rare. In this work, we examined the inflammatory activity of P. olfersii venom (10, 30 and 60 µg) in mouse gastrocnemius muscle 6 h after venom injection. Intramuscular injection of venom did not affect hematological parameters such as red cell count, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. The venom caused thrombocytopenia (at all three doses), leukopenia and lymphopenia (both at the two highest doses), as well as neutrophilia (30 µg), monocytosis (30 µg) and basophilia (10 µg). Of the cytokines that were screened [IL-1ß, IL-6, IL-10, IL-13, IL-17, TNF-α, IFN-γ, MIP-2 and KC] and IGF-1, only IGF-1 showed a significant increase in its circulating concentration, seen with 60 µg of venom; there were no significant changes in the cytokines compared to control mice. Histological analysis revealed the presence of edema, an inflammatory infiltrate and progressive myonecrosis. Edema and myonecrosis were greatest with 60 µg of venom, while the inflammatory infiltrate was greatest with 10 µg of venom. All venom doses caused the migration of polymorphonuclear and mononuclear leukocytes into muscle, but with no significant dose-dependence in the response. These findings show that, at the doses tested, P. olfersii venom does not cause hematological alterations and has limited effect on circulating cytokine concentrations. These data also confirm that the principal effects of the venom in mice are local edema, inflammatory cell infiltration and myonecrosis.
Assuntos
Colubridae , Venenos de Serpentes/toxicidade , Animais , Citocinas/sangue , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Doenças Hematológicas/induzido quimicamente , Inflamação/induzido quimicamente , Inflamação/patologia , Fator de Crescimento Insulin-Like I/análise , Masculino , Camundongos Endogâmicos C57BL , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , NecroseRESUMO
BACKGROUND: Sympathetic hyperactivity may be related to left ventricular (LV) dysfunction and baro- and chemoreflex impairment in hypertension. However, cardiac function, regarding the association of hypertension and baroreflex dysfunction, has not been previously evaluated by transesophageal echocardiography (TEE) using intracardiac echocardiographic catheter. METHODS AND RESULTS: We evaluated exercise tests, baroreflex sensitivity and cardiovascular autonomic control, cardiac function, and biventricular invasive pressures in rats 10 weeks after sinoaortic denervation (SAD). The rats (n = 32) were divided into 4 groups: 16 Wistar (W) with (n = 8) or without SAD (n = 8) and 16 spontaneously hypertensive rats (SHR) with (n = 8) or without SAD (SHRSAD) (n = 8). Blood pressure (BP) and heart rate (HR) did not change between the groups with or without SAD; however, compared to W, SHR groups had higher BP levels and BP variability was increased. Exercise testing showed that SHR had better functional capacity compared to SAD and SHRSAD. Echocardiography showed left ventricular (LV) concentric hypertrophy; segmental systolic and diastolic biventricular dysfunction; indirect signals of pulmonary arterial hypertension, mostly evident in SHRSAD. The end-diastolic right ventricular (RV) pressure increased in all groups compared to W, and the end-diastolic LV pressure increased in SHR and SHRSAD groups compared to W, and in SHRSAD compared to SAD. CONCLUSIONS: Our results suggest that baroreflex dysfunction impairs cardiac function, and increases pulmonary artery pressure, supporting a role for baroreflex dysfunction in the pathogenesis of hypertensive cardiac disease. Moreover, TEE is a useful and feasible noninvasive technique that allows the assessment of cardiac function, particularly RV indices in this model of cardiac disease.
Assuntos
Coração/fisiopatologia , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Artéria Pulmonar/fisiopatologia , Seio Aórtico/fisiopatologia , Disfunção Ventricular/fisiopatologia , Animais , Denervação Autônoma , Barorreflexo , Pressão Sanguínea , Ecocardiografia Transesofagiana , Teste de Esforço , Gânglios Parassimpáticos/fisiopatologia , Gânglios Parassimpáticos/cirurgia , Frequência Cardíaca , Hipertensão/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Masculino , Pressorreceptores/diagnóstico por imagem , Pressorreceptores/fisiopatologia , Artéria Pulmonar/diagnóstico por imagem , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Seio Aórtico/diagnóstico por imagem , Seio Aórtico/inervação , Disfunção Ventricular/diagnóstico por imagemRESUMO
BACKGROUND: Exercise training (ET) can reduce blood pressure (BP) and prevent functional disability. However, the effects of low volumes of training have been poorly studied, especially in elderly hypertensive patients. OBJECTIVES: To investigate the effects of a multi-component ET program (aerobic training, strength, flexibility, and balance) on BP, physical fitness, and functional ability of elderly hypertensive patients. METHODS: Thirty-six elderly hypertensive patients with optimal clinical treatment underwent a multi-component ET program: two 60-minute sessions a week for 12 weeks at a Basic Health Unit. RESULTS: Compared to pre-training values, systolic and diastolic BP were reduced by 3.6% and 1.2%, respectively (p<0.001), body mass index was reduced by 1.1% (p<0.001), and peripheral blood glucose was reduced by 2.5% (p=0.002). There were improvements in all physical fitness domains: muscle strength (chair-stand test and elbow flexor test; p<0.001), static balance test (unipedal stance test; p<0.029), aerobic capacity (stationary gait test; p<0.001), except for flexibility (sit and reach test). Moreover, there was a reduction in the time required to perform two functional ability tests: "put on sock" and "sit down, stand up, and move around the house" (p<0.001). CONCLUSIONS: Lower volumes of ET improved BP, metabolic parameters, and physical fitness and reflected in the functional ability of elderly hypertensive patients. Trial Registration RBR-2xgjh3.
Assuntos
Pressão Sanguínea , Terapia por Exercício , Hipertensão/fisiopatologia , Hipertensão/terapia , Aptidão Física , Idoso , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Fatores de TempoRESUMO
BACKGROUND: Exercise training (ET) can reduce blood pressure (BP) and prevent functional disability. However, the effects of low volumes of training have been poorly studied, especially in elderly hypertensive patients. OBJECTIVES: To investigate the effects of a multi-component ET program (aerobic training, strength, flexibility, and balance) on BP, physical fitness, and functional ability of elderly hypertensive patients. METHODS: Thirty-six elderly hypertensive patients with optimal clinical treatment underwent a multi-component ET program: two 60-minute sessions a week for 12 weeks at a Basic Health Unit. RESULTS: Compared to pre-training values, systolic and diastolic BP were reduced by 3.6% and 1.2%, respectively (p<0.001), body mass index was reduced by 1.1% (p<0.001), and peripheral blood glucose was reduced by 2.5% (p=0.002). There were improvements in all physical fitness domains: muscle strength (chair-stand test and elbow flexor test; p<0.001), static balance test (unipedal stance test; p<0.029), aerobic capacity (stationary gait test; p<0.001), except for flexibility (sit and reach test). Moreover, there was a reduction in the time required to perform two functional ability tests: "put on sock" and "sit down, stand up, and move around the house" (p<0.001). CONCLUSIONS: Lower volumes of ET improved BP, metabolic parameters, and physical fitness and reflected in the functional ability of elderly hypertensive patients. Trial Registration RBR-2xgjh3.
CONTEXTUALIZAÇÃO: O treinamento físico (TF) é capaz de reduzir a pressão arterial (PA) e prevenir o declínio da capacidade funcional. Entretanto, pouco tem sido estudado sobre os efeitos de menores volumes de treinamento em idosos com hipertensão arterial (HA). OBJETIVOS: Investigar os efeitos de um programa de TF multicomponente (treinamento aeróbico, força, flexibilidade e equilíbrio) na PA, aptidão física e capacidade funcional de idosos com HA. MÉTODOS: Trinta e seis idosos com HA e tratamento clínico otimizado foram submetidos a um programa de exercícios físicos multicomponente, com duas sessões semanais de 60 minutos cada, durante 12 semanas, em uma Unidade Básica de Saúde (UBS). RESULTADOS: Comparados aos valores antes do TF, observou-se redução de 3,6% da PA sistólica (p<0,001), de 1,2% da PA diastólica (p<0,001), de 1,1% do índice de massa corporal (IMC) (p<0,001) e de 2,5% da glicemia periférica em jejum (p=0,002). Observou-se melhora em todos os domínios da aptidão física, como força muscular (testes de levantar da cadeira e flexão de cotovelos, p<0,001); equilíbrio estático (teste de apoio unipodal, p=0,029), capacidade aeróbica (teste de marcha estacionária, p<0,001), com exceção da flexibilidade (teste de sentar e alcançar). Além disso, houve redução no tempo utilizado para realização de dois testes de avaliação da capacidade funcional, o de "calçar meias" e o de "sentar, levantar-se da cadeira e locomover-se pela casa" (p<0,001). CONCLUSÕES: O TF com duas sessões semanais em idosos hipertensos repercutiu na melhora dos indicadores metabólicos, da aptidão física e da capacidade funcional e atuou como auxiliar no controle da PA. Registro de Ensaios Clínicos RBR-2xgjh3.