OBJECTIVE: Our purpose was to clarify the mechanisms by which postmenopausal estrogen replacement therapy exerts its protective effect on cardiovascular risk. STUDY DESIGN: By means of a bidirectional Doppler ultrasonographic system we measured pulsatility index variations the internal carotid artery and middle cerebral artery in 25 early postmenopausal women during a 6-month period of hormone replacement therapy. Transdermal estradiol (50 micrograms/day) was continuously administered. A 12-day course of medroxyprogesterone acetate (10 mg/day) was added every second month. RESULTS: The pulsatility index showed a significant (p = 0.0001) reduction in both arteries after 6 weeks. At 22 weeks a 25% reduction was measured. No variation of the estrogen-induced pulsatility index reduction was observed at the end of every cyclic progestogen supplementation. CONCLUSIONS: In early postmenopausal women hormone replacement therapy causes a rapid reduction of pulsatility index in brain arteries. Cyclical progestational supplementation does not modify this positive effect on reactivity of the blood vessels.
OBJECTIVE: Our purpose was to clarify the mechanisms by which postmenopausal estrogen replacement therapy exerts its protective effect on cardiovascular risk. STUDY DESIGN: By means of a bidirectional Doppler ultrasonographic system we measured pulsatility index variations the internal carotid artery and middle cerebral artery in 25 early postmenopausal women during a 6-month period of hormone replacement therapy. Transdermal estradiol (50 micrograms/day) was continuously administered. A 12-day course of medroxyprogesterone acetate (10 mg/day) was added every second month. RESULTS: The pulsatility index showed a significant (p = 0.0001) reduction in both arteries after 6 weeks. At 22 weeks a 25% reduction was measured. No variation of the estrogen-induced pulsatility index reduction was observed at the end of every cyclic progestogen supplementation. CONCLUSIONS: In early postmenopausal women hormone replacement therapy causes a rapid reduction of pulsatility index in brain arteries. Cyclical progestational supplementation does not modify this positive effect on reactivity of the blood vessels.
Authors: Brian M Deegan; Farzaneh A Sorond; Andrew Galica; Lewis A Lipsitz; Gearoid O'Laighin; Jorge M Serrador Journal: Stroke Date: 2011-05-12 Impact factor: 7.914
Authors: Whitney Wharton; Carey E Gleason; Katelin R Lorenze; Tamara S Markgraf; Michele L Ries; Cynthia M Carlsson; Sanjay Asthana Journal: Am J Transl Res Date: 2009-01-20 Impact factor: 4.060
Authors: J N Barnes; R E Harvey; N A Eisenmann; K B Miller; M C Johnson; S M Kruse; B D Lahr; M J Joyner; V M Miller Journal: Climacteric Date: 2019-01-21 Impact factor: 3.005