title: Immunohistochemical expression of intrarenal renin angiotensin system components in response to tempol in rats fed a high salt diet.
abstract: OBJECTIVE
  To determine the effect of tempol in normal rats fed high salt on arterial pressure and the balance between antagonist components of the renal renin-angiotensin system.
  
  
  METHODS
  Sprague-Dawley rats were fed with 8% NaCl high-salt (HS) or 0.4% NaCl (normal-salt, NS) diet for 3 wk, with or without tempol (T) (1 mmol/L, administered in drinking water). Mean arterial pressure (MAP), glomerular filtration rate (GFR), and urinary sodium excretion (UVNa) were measured. We evaluated angiotensin II (Ang II), angiotensin 1-7 (Ang 1-7), angiotensin converting enzyme 2 (ACE2), mas receptor (MasR), angiotensin type 1 receptor (AT1R) and angiotensin type 2 receptor (AT2R) in renal tissues by immunohistochemistry.
  
  
  RESULTS
  The intake of high sodium produced a slight but significant increase in MAP and differentially regulated components of the renal renin-angiotensin system (RAS). This included an increase in Ang II and AT1R, and decrease in ACE-2 staining intensity using immunohistochemistry. Antioxidant supplementation with tempol increased natriuresis and GFR, prevented changes in blood pressure and reversed the imbalance of renal RAS components. This includes a decrease in Ang II and AT1R, as increase in AT2, ACE2, Ang (1-7) and MasR staining intensity using immunohistochemistry. In addition, the natriuretic effects of tempol were observed in NS-T group, which showed an increased staining intensity of AT2, ACE2, Ang (1-7) and MasR.
  
  
  CONCLUSIONS
  These findings suggest that a high salt diet leads to changes in the homeostasis and balance between opposing components of the renal RAS in hypertension to favour an increase in Ang II. Chronic antioxidant supplementation can modulate the balance between the natriuretic and antinatriuretic components of the renal RAS.
authors.affiliation: Gabriel Cao, Silvana Lorena Della Penna, Nicolás Martín Kouyoumdzian, Marcelo Roberto Choi, Belisario Enrique Fernández, Jorge Eduardo Toblli, María Inés Rosón, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1122AAJ, Argentina.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Cao
authors.affiliation: Gabriel Cao, Silvana Lorena Della Penna, Nicolás Martín Kouyoumdzian, Marcelo Roberto Choi, Belisario Enrique Fernández, Jorge Eduardo Toblli, María Inés Rosón, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1122AAJ, Argentina.
authors.forename: Silvana Lorena
authors.initials: SL
authors.lastname: Della Penna
authors.affiliation: Gabriel Cao, Silvana Lorena Della Penna, Nicolás Martín Kouyoumdzian, Marcelo Roberto Choi, Belisario Enrique Fernández, Jorge Eduardo Toblli, María Inés Rosón, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1122AAJ, Argentina.
authors.forename: Nicolás Martín
authors.initials: NM
authors.lastname: Kouyoumdzian
authors.affiliation: Gabriel Cao, Silvana Lorena Della Penna, Nicolás Martín Kouyoumdzian, Marcelo Roberto Choi, Belisario Enrique Fernández, Jorge Eduardo Toblli, María Inés Rosón, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1122AAJ, Argentina.
authors.forename: Marcelo Roberto
authors.initials: MR
authors.lastname: Choi
authors.affiliation: Gabriel Cao, Silvana Lorena Della Penna, Nicolás Martín Kouyoumdzian, Marcelo Roberto Choi, Belisario Enrique Fernández, Jorge Eduardo Toblli, María Inés Rosón, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1122AAJ, Argentina.
authors.forename: Susana
authors.initials: S
authors.lastname: Gorzalczany
authors.affiliation: Gabriel Cao, Silvana Lorena Della Penna, Nicolás Martín Kouyoumdzian, Marcelo Roberto Choi, Belisario Enrique Fernández, Jorge Eduardo Toblli, María Inés Rosón, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1122AAJ, Argentina.
authors.forename: Belisario Enrique
authors.initials: BE
authors.lastname: Fernández
authors.affiliation: Gabriel Cao, Silvana Lorena Della Penna, Nicolás Martín Kouyoumdzian, Marcelo Roberto Choi, Belisario Enrique Fernández, Jorge Eduardo Toblli, María Inés Rosón, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1122AAJ, Argentina.
authors.forename: Jorge Eduardo
authors.initials: JE
authors.lastname: Toblli
authors.affiliation: Gabriel Cao, Silvana Lorena Della Penna, Nicolás Martín Kouyoumdzian, Marcelo Roberto Choi, Belisario Enrique Fernández, Jorge Eduardo Toblli, María Inés Rosón, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1122AAJ, Argentina.
authors.forename: María Inés
authors.initials: MI
authors.lastname: Rosón
keywords: Angiotensin 1-7; Angiotensin II; High sodium diet; Kidney; Tempol