ESTROGEN RELATED MECHANISMS OF HYPERTENSION IN MENOPAUSAL WOMEN.

The aim of our investigation was to establish the role of estrogens in the pathogenesis of hypertension during menopause. Menopausal women (40-55 years) with hypertension who had been admitted to "The N. Kipshidze Central University Clinic" (Tbilisi, Georgia) during 2011-2015 and without hypertension were investigated. Essential hypertension was defined as elevated blood pressure while in a sitting position, exceeding 160±10/90±10 mm Hg 60/95 mm Hg, for three consecutive measurements over a period of at least 4 weeks. Determination and verification of menopause was provided based on the criteria of at least 12 months of amenorrhea. All the patients had given their informed consent before any procedure. Study protocol was approved by Local Ethical Committee of Davit Agmashenebeli University. In each group blood content of estradiol, free nitric oxide (NO) and nitrosilated hemoglobin (HbNO), endothelin-1 and angiotensin II (ANG) were investigated. Decrease free nitric oxide (NO) (by 10%) and increase in endothelin-1 (by 14%) and Angiotensin II (ANG) (by 12%) content in the blood of menopausal women with hypertension were identified. In some patients with hypertension it was detected low intensity of NOHb EPR signal in blood (~1,5±0,07 mm/mg). In blood of hypertensive postmenopausal women there was revealed statistically significant correlation between estrogen level and NO content (r=-0,7935, p=0,0061), estrogen level and ANG II content (r=-0,7080, p=0,0328), statistically nonsignificant dependence between NOHb EPR signal intensity and estradiol content (r=-0,29, p=0,12). In normotensive postmenopausal women correlation between blood estrogen and NO level, blood estrogen and ANGII level was not statistically significant (r=-0,4342, p=0,2429; r=-0,2676, p=0,4547). These data indicate that in postmenopausal women in the regulation of arterial pressure in addition to the estrogens involve other factors, like as was shown in our previous investigation, oxidative stress. The results of our studies indicate on the complexity mechanisms of hypertension in postmenopausal women. Identification of these factors, including their cause-effect relations, is necessary for the timely prevention and effective correction of hypertension in postmenopausal women.