Dynamic resistance training decreases sympathetic tone in hypertensive ovariectomized rats

Autor(es)

Shimojo, G. L. ^[1] ; Palma, R. K. ^[1] ; Brito, J. O. ^[1] ; Sanches, I. C. ^[1] ; Irigoyen, M. C. ^[2] ; De Angelis, K. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Nove Julho, Programa Ciencias Reabilitacao, Lab Fisiol Translacional, Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Fac Med, Inst Coracao, Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Medical and Biological Research; v. 48, n. 6, p. 523-527, JUN 2015.
• Citações Web of Science: 10

Resumo

The aim of this study was to investigate the effects of resistance exercise training on hemodynamics and cardiac autonomic control in ovariectomized spontaneously hypertensive rats. Female rats were divided into 4 groups: sedentary control (SC), sedentary hypertensive (SH), sedentary hypertensive ovariectomized (SHO), and resistance-trained hypertensive ovariectomized (RTHO). Resistance exercise training was performed on a vertical ladder (5 days/week, 8 weeks) at 40-60% maximal load. Direct arterial pressure was recorded. Vagal and sympathetic tones were measured by heart rate (HR) responses to methylatropine (3 mg/kg, iv) and propranolol (4 mg/kg, iv). Ovariectomy resulted in additional increases in blood pressure in hypertensive rats and was associated with decreased vagal tone. Resistance exercise trained rats had lower mean arterial pressure than untrained rats (RTHO: 159±2.2 vs SHO: 177±3.4 mmHg), as well as resting bradycardia (RTHO: 332±9.0 vs SHO: 356±5 bpm). Sympathetic tone was also lower in the trained group. Moreover, sympathetic tone was positively correlated with resting HR (r=0.7, P<0.05). The additional arterial pressure increase in hypertensive rats caused by ovarian hormone deprivation was attenuated by moderate-intensity dynamic resistance training. This benefit may be associated with resting bradycardia and reduced cardiac sympathetic tone after training, which suggests potential benefits of resistance exercise for the management of hypertension after ovarian hormone deprivation. (AU)

• Processo FAPESP: 12/20141-5 - Efeitos do treinamento físico aeróbio, resistido ou combinado em modelos experimentais de disfunções cardiometabólicas associadas à privação dos hormônios ovarianos
• Beneficiário: Kátia de Angelis Lobo D Avila
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/16441-0 - Efeitos do treinamento físico aeróbio ou resistido em parâmetros autonômicos e de estresse oxidativo em ratas hipertensas ooforectomizadas
• Beneficiário: Renata Kelly da Palma
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 12/02023-5 - Efeitos do treinamento físico resistido no perfil hemodinâmico e no controle autonômico cardiovascular de ratas hipertensas ooforectomizadas
• Beneficiário: Guilherme Lemos Shimojo Ferreira
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 13/07869-2 - Efeitos da Associação de treinamento físico aeróbio e resistido em parâmetros autonômicos e de estresse oxidativo em ratas hipertensas ooforectomizadas.
• Beneficiário: Guilherme Lemos Shimojo Ferreira
• Modalidade de apoio: Bolsas no Brasil - Mestrado