Renovascular remodeling and renal injury after extended angiotensin II infusion

Autor(es)

Malavazzi Casare, Fernando Augusto ^[1] ; Thieme, Karina ^[2] ; Costa-Pessoa, Juliana Martins ^[1] ; Rossoni, Luciana Venturini ^[1] ; Couto, Gisele Kruger ^[1] ; Fernandes, Fernanda Barrinha ^[3] ; Casarini, Dulce Elena ^[3] ; Oliveira-Souza, Maria ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, BR-05508900 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Sch Med, Lab Cellular & Mol Endocrinol, BR-05508900 Sao Paulo - Brazil

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

• Tipo de documento: Artigo Científico
• Fonte: AMERICAN JOURNAL OF PHYSIOLOGY-RENAL PHYSIOLOGY; v. 310, n. 11, p. F1295-F1307, JUN 1 2016.
• Citações Web of Science: 11

Resumo

Chronic angiotensin II (ANG II) infusion for 1 or 2 wk leads to progressive hypertension and induces inward hypertrophic remodeling in preglomerular vessels, which is associated with increased renal vascular resistance (RVR) and decreased glomerular perfusion. Considering the ability of preglomerular vessels to exhibit adaptive responses, the present study was performed to evaluate glomerular perfusion and renal function after 6 wk of ANG II infusion. To address this study, male Wistar rats were submitted to sham surgery (control) or osmotic minipump insertion (ANG II 200 ng.kg(-1).min(-1), 42 days). A group of animals was treated or cotreated with losartan (10 mg.kg(-1).day(-1)), an AT(1) receptor antagonist, between days 28 and 42. Chronic ANG II infusion increased systolic blood pressure to 185 +/- 4 compared with 108 +/- 2 mmHg in control rats. Concomitantly, ANG II-induced hypertension increased intrarenal ANG II level and consequently, preglomerular and glomerular injury. Under this condition, ANG II enhanced the total renal plasma flow (RPF), glomerular filtration rate (GFR), urine flow and induced pressure natriuresis. These changes were accompanied by lower RVR and enlargement of the lumen of interlobular arteries and afferent arterioles, consistent with impairment of renal autoregulatory capability and outward preglomerular remodeling. The glomerular injury culminated with podocyte effacement, albuminuria, tubulointerstitial macrophage infiltration and intrarenal extracellular matrix accumulation. Losartan attenuated most of the effects of ANG II. Our findings provide new information regarding the contribution of ANG II infusion over 2 wk to renal hemodynamics and function via the AT(1) receptor. (AU)

• Processo FAPESP: 11/14022-0 - Efeitos da interação do sistema-renina-angiotensina-aldosterona e endotelinas-1 e 3 sobre a função renal
• Beneficiário: Fernando Augusto Malavazzi Casare
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 13/19569-3 - Efeitos da endotelina 3 e da leptina na morfologia e função renal in vivo: participação do sistema renina-angiotensina intrarrenal
• Beneficiário: Maria Oliveira de Souza
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/23087-4 - Estudo molecular e funcional de transportadores de membrana
• Beneficiário: Gerhard Malnic
• Modalidade de apoio: Auxílio à Pesquisa - Temático