Vascular response to atrial natriuretic peptide chronic treatment in hypertension.

COSTA MA; ROMERO M; BOUCHET G; SAVIGNANO L; CANIFFI C; ELESGARAY R; MAC LAUGHLIN M; ARRANZ C

Milàn

Congreso; 21st European Meeting on Hypertension; 2011

European Society of Hypertension

Abundant evidence indicates that high blood pressure is assocaited to endothelial dysfunction and vascular damage. In previous studies we demonstrated that atrial natriuretic peptide (ANP) increased cardiac abd renal nitric oxide synthase (NOS) activity in spontaneously hypertensive rats (SHR). The aim was to investigate vascular effects of chronic infusion with ANP in SHR and to compare this response in male (M) and female (F) rats. Methods: 10 weeks-old M and F SHR were infuse (14 days, subcutaneous osmotic pump) with ANP (100 ng/hr/rat) or saline (S). Systolic blood pressure (SBP, mmHg) was recorded and nitrites and nitrates excretion (NOx, metabolic end poducts of NO, nmol/min.100g) was determined at the end of the experimental period. The animals were sacrificed to perform morphological studies in thoracic aorta sections stained with haematoxylin-eosine 8media thickness, um; media/lumen ration, um/mm) and to determine fibrosis signs with picrosirius rea and Masson´s Trirchromic (Score). Aortic NOS activity (14C L-arginine, pmol/gtissue.min) was determined. Cardiac ventricle and kidney sections were stained by picrosirius red to evaluate perivascular collagen in coronary and renal arteries. Results: ver Tabla en Full text o Texto In coronary and renal arteries , perivascular collagen area was higher in male than in female SHR and ANP treatment reduced this parameter in both gender. Conclusions: ANP treatment inceased vascular NO system activity, improving aortic wall properties and modifying coronary and renal arteries remodelling in SHR.