system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Angiotensin I, Angiotensin II, Blood Flow Velocity, Double-Blind Method, Estradiol, Estrogen Replacement Therapy, Female, Forearm, Humans, Middle Aged, Postmenopause, Vasoconstrictor Agents.
user
Does 17ss oestradiol attenuate the response to angiotensin I and II during long term therapy in postmenopausal women? Context: It is thought that oestrogen replacement therapy may reduce the conversion of angiotensin I to angiotensin II in postmenopausal women by inhibiting angiotensin converting enzyme. We sought to determine the effects of 3 months oestrogen replacement therapy (ERT) on the response to angiotensin I and II in postmenopausal women. Eighteen postmenopausal women were randomised to either three months of 2 mg oral oestradiol or placebo in a double blind, placebo controlled, protocol. Change in forearm blood flow (FBF), in response to brachial arterial infusion of increasing concentrations of angiotensin I and angiotensin II was measured, pre-randomisation, after 1 months randomised therapy and after 3 months therapy, using venous occlusion plethysmography. Oestrogen treatment had no effect on baseline FBF. The mean (SD) peak reductions in FBF with 64 pmol/min angiotensin I pre-randomisation, after 1 month and after 3 months treatment with placebo were 62(11), 65(15) and 57(8)%. The corresponding reductions with the peak dose of angiotensin II (16 pmol/min) were 53(8), 48(12) and 47(11)%. In the oestradiol group, the peak responses to angiotensin I were 56(8), 53(11) and 44(29)% pre-randomisation, after 1 months treatment and after 3 months treatment. The corresponding reductions in response to angiotensin II were 37(15), 47(15) and 45(19)%. Oestradiol did not affect the response to either angiotensin I or angiotensin II.
assistant
This study does not support the idea that ERT might exert a cardioprotective effect through inhibition of the renin-angiotensin system. Final Decision: no