Aldosterone Contributes to Sympathoexcitation in Renovascular Hypertension

Author(s)

Lincevicius, Gisele S. ^[1] ; Shimoura, Caroline G. ^[1] ; Nishi, Erika E. ^[1] ; Perry, Juliana C. ^[2] ; Casarini, Dulce E. ^[3] ; Gomes, Guiomar N. ^[1] ; Bergamaschi, Cassia T. ^[1] ; Campos, Ruy R. ^[1]

Affiliation

^[1] Univ Fed Sao Paulo, Escola Paulista Med, Dept Physiol, Sao Paulo - Brazil

^[2] Univ Fed Sao Paulo, Dept Psychobiol, Escola Paulista Med, Sao Paulo - Brazil

^[3] Univ Fed Sao Paulo, Escola Paulista Med, Dept Med, Div Nephrol, Sao Paulo - Brazil

• Document type: Journal article
• Source: AMERICAN JOURNAL OF HYPERTENSION; v. 28, n. 9, p. 1083-1090, SEP 2015.
• Web of Science Citations: 15

Abstract

BACKGROUND Although angiotensin II (Ang II) is essential to the development of renovascular hypertension, aldosterone plays a role as well. Recent studies have demonstrated a cross-talk between Ang II type 1 and mineralocorticoid receptors in the brain and kidneys. However, the role of aldosterone in the autonomic and renal dysfunction of renovascular hypertension is not well understood. AIM The current study evaluated whether aldosterone contributes to cardiovascular and renal dysfunction in the 2 kidney-1 clip (2K1C) model. METHODS Mean arterial pressure (MAP) and baroreceptor reflex for control of the heart rate were evaluated in 2K1C treated or not treated with spironolactone (200 mg/kg/day, 7 days). Tonic and reflex control of renal sympathetic nerve activity (rSNA) were assessed in urethane-anaesthetized rats. Plasma renin activity (PRA), kidney renin protein expression, renal injury, and central AT(1) receptor protein expression were assessed. RESULTS Spiro reduced MAP (198 +/- 4 vs. 170 +/- 9 mm Hg; P < 0.05), normalized rSNA (147 +/- 9 vs. 96 +/- 10 pps; P < 0.05), and increased renal baroreceptor reflex sensitivity in the 2K1C rats. Spiro reduced alpha-smooth muscle actin expression in the nonclipped kidney in the 2K1C group (5 +/- 0.6 vs. 1.1 +/- 0.2%; P < 0.05). There was no change in PRA; however, a decrease in renin protein expression in the nonclipped kidney was found in the 2K1C treated group (217 +/- 30 vs. 160 +/- 19%; P < 0.05). Spiro treatment decreased AT1 receptor in the central nervous system (CNS) only in 2K1C rats (138 +/- 10 vs. 84 +/- 12%; P < 0.05). CONCLUSION Aldosterone contributes to autonomic dysfunction and intrarenal injury in 2K1C, these effects are mediated by the CNS. (AU)

• FAPESP's process: 10/04333-6 - Role of the aldosterone in oxidative stress and sympathetic activity in renovascular hypertension in Wistar rats
• Grantee: Gisele Silvério Lincevicius
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 13/22522-9 - Role of renal sympathetic nerves on cardiovascular and renal alterations in renovascular hypertension
• Grantee: Ruy Ribeiro de Campos Junior
• Support Opportunities: Regular Research Grants