IQUIMEFA   05518
INSTITUTO QUIMICA Y METABOLISMO DEL FARMACO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Hypertension and menopause: Vascular effects of the angiotensin converting enzyme in spontaneously hypertensive rats.
Autor/es:
ZILBERMAN JUDITH; GONZALO PINEDA; PEREYRA S; ELESGARAY ROSANA; COSTA MARIA DE LOS ANGELES; ARRANZ CRISTINA
Lugar:
Milan
Reunión:
Congreso; XXIII European Meeting on Hypertension; 2013
Institución organizadora:
European Society of Hypertension
Resumen:
Cardiovascular disease risks in women increase after menopause. The responsible mechanisms for the blood pressure increase in menopausal women are not known. There are multiple factors related to the development of hypertension: an increase in the activity of the angiotensin I and II (Ang II) converting enzymes (ACE), changes in expression and activity of Ang II receptors type 1 (AT1) receptors. The activation of such receptor leads to vasoconstriction and increases the concentration of free radicals at vascular level, increasing oxidative stress and vascular lesions. All these changes promote BP increase. The estrogen vascular protection effect is attributed to different mechanisms, such as renin-angiotensin system (RAS) components control, oxidative stress decrease and nitric oxide (NO) system activation. Aims: To evaluate the effects of enalapril, an ACE inhibitor (ACEI), on vascular morphology and nitric oxide synthase (NOS) activity in spontaneous hypertensive menopausal rats (SHR). Methods: The 14-month old SHR female rats were divided in two groups: 1) a group treated with enalapril for 30 days (15 mg /kg/day) and 2) control group using ad libitum water. We measured systolic blood pressure (SBP) (indirect method, tail-cuff). In thoracic aorta, NOS activity (pmol 14C Lcitrulline/ g.tissue. min) and media thickness (ìm/mm) hematoxiline eosin) were measured. Perivascular collagen area (collagen area/lumen area) in renal and coronary arteries was determined in heart and kidney slices stained with Sirius Red. Results: Enalapril treatment decreased SBP, increased vascular NOS activity and decreased perivascular collagen area in coronary and renal arteries, as well as, diminished media thickness in the thoracic aorta. Conclusions: RAS inhibition in menopausal SHR rats increases the aorta NO system activity and it may be related to the beneficial effects observed in its structure. On the other hand, the decrease in coronary and renal perivascular fibrosis may reveal an improvement of the cardiac and renal vascular function.