title: Inhibition of PDE5 Restores Depressed Baroreflex Sensitivity in Renovascular Hypertensive Rats.
abstract: Renal artery stenosis is frequently associated with resistant hypertension, which is defined as failure to normalize blood pressure (BP) even when combined drugs are used. Inhibition of PDE5 by sildenafil has been shown to increase endothelial function and decrease blood pressure in experimental models. However, no available study evaluated the baroreflex sensitivity nor autonomic balance in renovascular hypertensive rats treated with sildenafil. In a translational medicine perspective, our hypothesis is that sildenafil could improve autonomic imbalance and baroreflex sensitivity, contributing to lower blood pressure. Renovascular hypertensive 2-kidney-1-clip (2K1C) and sham rats were treated with sildenafil (45 mg/Kg/day) during 7 days. At the end of treatment, BP and heart rate (HR) were recorded in conscious rats after a 24-h-recovery period. Spontaneous and drug-induced baroreflex sensitivity and autonomic tone were evaluated; in addition, lipid peroxidation was measured in plasma samples. Treatment was efficient in increasing both spontaneous and induced baroreflex sensitivity in treated hypertensive animals. Inhibition of PDE5 was also capable of ameliorating autonomic imbalance in 2K1C rats and decreasing systemic oxidative stress. Taken together, these beneficial effects resulted in significant reductions in BP without affecting HR. We suggest that sildenafil could be considered as a promising alternative to treat resistant hypertension.
authors: Centro de Biotecnologia, Universidade Federal da Paraíba Joao Pessoa, Brazil.
authors: Clênia de Oliveira
authors: CO
authors: Cavalcanti
authors: Centro de Ciências Médicas, Universidade Federal da ParaíbaJoao Pessoa, Brazil; Centro de Ciências da Saúde, Universidade Federal da ParaíbaJoao Pessoa, Brazil.
authors: Rafael R
authors: RR
authors: Alves
authors: Centro de Ciências Médicas, Universidade Federal da ParaíbaJoao Pessoa, Brazil; Centro de Ciências da Saúde, Universidade Federal da ParaíbaJoao Pessoa, Brazil.
authors: Alessandro L
authors: AL
authors: de Oliveira
authors: Centro de Biotecnologia, Universidade Federal da Paraíba Joao Pessoa, Brazil.
authors: Josiane de Campos
authors: JC
authors: Cruz
authors: Centro de Biotecnologia, Universidade Federal da Paraíba Joao Pessoa, Brazil.
authors: Maria do Socorro
authors: MS
authors: de França-Silva
authors: Centro de Biotecnologia, Universidade Federal da Paraíba Joao Pessoa, Brazil.
authors: Valdir de Andrade
authors: VA
authors: Braga
authors: Centro de Biotecnologia, Universidade Federal da ParaíbaJoao Pessoa, Brazil; Centro de Ciências da Saúde, Universidade Federal da ParaíbaJoao Pessoa, Brazil.
authors: Camille de Moura
authors: CM
authors: Balarini
keywords: angiotensin-II; baroreflex; nitric oxide; resistant hypertension; sildenafil