ABSTRACT
Both exercise and postmenopausal estrogen therapy augment endothelial function through increasing bioavailability of nitricoxide [NO]. The aim of this study was to: 1- determine the effects of acute bouts of exercise on brachial artery endothelium dependent flow mediated vasodilatation FMD in postmenopausal women. 2- Whether these responses were augmented by the concurrent use of oral estrogen. 3- Whether these two interventions independently or together achieve FMD values observed in pre menopausal women. This study was conducted on 30 apparently healthy post menopausal women their mean of age was [54 +/- 4 years old]. FMD was quantified during supine rest and again 60 minutes after treadmill exercise for 45 minute at 60% v[02] max - subjects were studied twice, before and after 4 weeks of oral estradiol. The normal reference values was obtained from concurrent determinant of FMD in 30 pre menopausal women their mean of age was [28 +/- 2] years old under identical basal conditions. flow mediated vasodilatation in post menopausal women markedly impaired when compared with pre menopausal women. The mean of absolute diameter change in brachial artery for flow mediated dilatation in post menopausal women was significantly less than premenopausal women [2.01 +/- 0.2mm [6.1%] Vs 4.1 +/- 0.4mm [12%] P<0.05]. After exercise the absolute change in the brachial artery diameter for FMD in postmenopausal women significantly approximate normal values [3.8 +/- 0.3mm [11.4%] P<0.05]. In contrast after estrogen therapy the mean of absolute brachial artery diameter change for FMD was augmented at rest [P < 0.01] but was not further enhanced after exercise. [3.7 +/- 1.32 mm [11.5%] VS 3.5 +/- 1.4mm [10.5%] P > 0.05]. Both interventions increased FMD to values in pre menopausal women. in post menopausal women both acute exercise and oral estrogen normalize FMD. However there effects weren't additive so these results reinforce that exercise is an alternative non pharmacological intervention to estrogen in post menopausal women with endothelial dysfunction