Effects of atrial natriuretic peptide chronic treatment on arterial blood pressure and renal nitric oxide system in spontaneously hypertensive rats

COSTA MARÍA DE LOS ÁNGELES; RODRIGUEZ IERASE DANIELA; ELESGARAY ROSANA; VISINTINI JAIME MARIA FLORENCIA; CANIFFI CAROLINA; BALASZCZUK ANA MARÍA; MAC LAUGHLIN MYRIAM; ARRANZ CRISTINA

Berlín

Congreso; Eighteenth European Meeting of Hypertension. 22nd Scientific Meeting of the International Society of Hypertension; 2008

European Society of Hypertension. International Society of Hypertension.

Objective: The aim was to study the effects of chronic atrial natriuretic peptide (ANP) treatment on systolic blood pressure(SBP) and renal nitric oxide(NO)system in spontaneously hypertensive rats (SHR). Methods: 8-weeks (8W) and 12-weeks (12W) old SHR and normotensive Wistar-Kyoto rats (WKY) were infused subcutaneously (osmotic pumps) with saline (NaCl 0.9%) or ANP (100 ng/hour.rat), during 7 days. SBP was recorded and nitrites and nitrates excretion (NOx, end products of NO) were determined during the experimental time. At the end of this period, the animals were sacrificed by decapitation and NO synthase (NOS) activity (using [14C] L-arginine as substrate) were determined in renal medulla and cortex. Results: Chronic infusion of ANP diminished SBP (8W: WKY= -8±2 vs SHR= -15±6 mmHg; 12W: WKY= -13±3 vs SHR= -25±10 mmHg, ns) and increased NOx (8W: WKY= 35±8 % vs SHR= 18±4 %*; 12W: WKY= 41±10 % vs SHR= 23±4 %, *p