The role of estrogens in pathogenesis of age-related arterial hypertension

Several factors are contributing to menopausal hypertensión; the role of estrogens in patogénesis of hypertensión in menopausal women have not completely established. The aim of the present investigation was to study some aspects of the role of estrogens in the pathogenesis of hypertension during menopause. 93 women with hypertension, who are referred to the Central Clinic of Tbilisi State Medical University (Georgia) during 2009-2011 were investigated. Women were divided into 2 groups: 1 - reproducvtive age group (43 patients); 2 - menopause age group (50 patients). In each group we investigated estradiole, oxygen (O2-), lipid (LOO.) reactive species, NO and endotheline content and antioxidant enzymes (SOD, catalase, GR) activity. The results of study reveal increased of superoxide - and lipoperoxide - radicals, as well as of endothelin сontent in blood of menopausal women, while concentration of free nitric oxide decreased; at the same time activity of catalase increased (by 50%), GR reduced significantly (by 38%) and SOD's activity didn't change in comparision to reproductive aged group. Negative correlation between the HbNO and estradiole content in blood of reproductive aged women was established (r=-0,60, p=0.03); no dependence between these two parameters in menopausal aged women was revealed (r=-0, 29, p=0,12). It was concluded, that in women of reproductive age probability and risk of hypertension grows in the presence of additional risk factors, such as oxidative stress and/or fluctuations in estrogen's level towards insufficiency, which leads to reduction of nitric oxide content due to its oxidative transformation in peroxinitrite, or enhanced inclusion in HbNO complexes, whereas development of hypertension in postmenopausal women may develop by different mechanisms, might including inflammation.