title: Interaction of central Angiotensin II and estrogen on systolic blood pressure in female DOCA-salt treated rats.
abstract: BACKGROUND
  There is a probable interaction of central angiotensin II (Ang II) and estrogen (Est) on blood pressure in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Therefore, in the present study, the interaction between Ang II and Est in ovariectomized (Ovx) and Sham rats that were treated with DOCA- salt was evaluated.
  
  
  METHODS
  The female rats were divided into 10 groups as follows: Sham, Ovx, Sham-DOCA, Ovx-DOCA, Sham-DOCA-estrogen (E), Ovx DOCA-E, Sham-DOCA-losartan (L), Ovx-DOCA-L, Sham-DOCA-L-E, and Ovx-DOCA-L-E. The Est groups received estradiol valerate (2 mg/kg; daily; subcutaneously (s.c)) for four weeks. Following that, several doses of Ang II (0.5, 5, 50, 500, 5000 ng/5 μl) were injected via the intracerebroventricular (i.c.v) route and the changes in systolic blood pressure (SBP) were evaluated. In the losartan groups, 200 μg losartan was injected (i.c.v) 15 minutes after the Ang II injection and the blood pressure was recorded. Treatment by DOCA was performed by removal of one kidney, injection of DOCA (45 mg/kg i.p), and adding of sodium chloride (NaCl) (1%) and potassium chloride (KCl) (0.1%) in the drinking water.
  
  
  RESULTS
  The SBP was increased by Ang II and this effect in DOCA-salt treated rat was higher than in the untreated groups. The effect of Ang II on SBP in groups that were treated with Est and L was lower than that in the DOCA-salt groups. Increase in SBP was strongly attenuated by Ang II in groups that were co-treated with both Est and L compared to the DOCA-treated rats. These results showed that Est significantly attenuated the effect of central Ang II on SBP in the DOCA-salt treated rats.
  
  
  CONCLUSIONS
  We suggest that there are interactions between E and Ang II in the control of blood pressure in DOCA-salt treated rats.
authors.affiliation: Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Marzieh
authors.initials: M
authors.lastname: Kafami
authors.affiliation: Neurocognetive Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Hosseini
authors.affiliation: Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Saeed
authors.initials: S
authors.lastname: Niazmand
authors.affiliation: Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Neurocognetive Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mousa Alreza
authors.initials: MA
authors.lastname: Hadjzadeh
authors.affiliation: Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Esmaeil
authors.initials: E
authors.lastname: Farrokhi
authors.affiliation: Neurocognetive Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Tahereh
authors.initials: T
authors.lastname: Mazloum
authors.affiliation: Neurogenic Inflammation Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mohammad Naser
authors.initials: MN
authors.lastname: Shafei
keywords: Ang II; DOCA-salt; Ovx; blood pressure; estrogen; losartan