Effects of dietary salt load and salt depletion on the course of hypertension and angiotensin II levels in male and female heterozygous Ren-2 transgenic rats.
BACKGROUND
In the present study we evaluated plasma and kidney angiotensin II (ANG II) levels in female and male Ren-2 transgenic rats (TGR) in comparison to age-matched female and male normotensive Hannover Sprague-Dawley rats.


METHODS
The rats were maintained on a normal sodium (NS) diet (0.6% NaCl) or fed a high sodium (HS) diet (2% NaCl) for 4 days or were sodium depleted by administration of 40 mg furosemide per liter drinking water overnight followed by 3 days of low sodium diet (0.01% NaCl) (LS + F). ANG II levels were determined by radioimmunoassay.


RESULTS
Female TGR at the age of 38 days were already hypertensive and had developed cardiac hypertrophy, whereas male TGR at this age still exhibited a normotensive phenotype. HS diet increased the blood pressure (BP) but did not alter the ANG II levels in TGR at any age. LS + F decreased the BP without significant change in ANG II concentrations in TGR. Female TGR responded to salt loading and salt depletion by more pronounced changes in BP than male TGR.


CONCLUSIONS
Female TGR develop hypertension more rapidly and the salt-sensitive component of hypertension is more pronounced in female than in male TGR.
Husková
Zuzana
Z
Department of Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
Kramer
Herbert
H
Vanourková
Zdenka
Z
Thumová
Monika
M
Malý
Jan
J
Opocenský
Martin
M
Skaroupková
Petra
P
Kolský
Alexander
A
Vernerová
Zdena
Z
Cervenka
Ludek
L
D000804:Angiotensin II / Q000097:blood* / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D030801:Animals, Genetically Modified; D001794:Blood Pressure; D006332:Cardiomegaly / Q000097:blood / Q000178:diet therapy; D005260:Female; D006579:Heterozygote; D006977:Hypertension, Renal / Q000097:blood / Q000178:diet therapy*; D007668:Kidney / Q000098:blood supply / Q000503:physiopathology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012083:Renin / Q000235:genetics* / Q000378:metabolism; D012084:Renin-Angiotensin System / Q000502:physiology; D012727:Sex Characteristics; D017673:Sodium Chloride, Dietary / Q000627:therapeutic use*
D017673:Sodium Chloride, Dietary; D000804:Angiotensin II; D012083:Renin