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06:51
Ovariectomy and 17β-estradiol Replacement in Rats and Mice: A Visual Demonstration
Published on: June 7, 2012
Transdermal estrogen replacement therapy and vasomotor response.
M Kashiwagi1, Y Seino, H Tsukamoto
1First Department of Internal Medicine, Nippon Medical School, Tokyo, Japan.
Japanese Heart Journal
|October 19, 2001
Summary
Transdermal estrogen therapy did not improve brachial artery endothelial function in postmenopausal women. However, it did reduce cutaneous blood flow, possibly by alleviating hot flashes.
Area of Science:
- Endocrinology
- Cardiovascular Physiology
Background:
- Acute estrogen administration benefits endothelial function in postmenopausal women.
- Chronic effects of transdermal estrogen replacement therapy (ERT) on vascular function are less understood.
Purpose of the Study:
- To investigate the chronic effects of a standard dose of transdermal ERT on endothelial function and cutaneous blood flow in postmenopausal women.
- To assess changes in plasma hormone and lipid levels following transdermal ERT.
Main Methods:
- 12 normolipidemic postmenopausal women received transdermal ERT (0.025 mg/day for 4 weeks).
- Flow-mediated vasodilation of the brachial artery was assessed using B-mode ultrasound.
- Forearm cutaneous blood flow and reactive hyperemia were measured using laser Doppler flowmetry.
Main Results:
- No significant changes were observed in resting vascular diameter, flow-mediated vasodilation, or time to peak vasodilation.
- Resting forearm cutaneous blood flow significantly decreased post-ERT.
- Reactive hyperemia showed a slight decrease in peak time and overall change, potentially linked to reduced hot flush symptoms.
Conclusions:
- Low-dose transdermal ERT did not enhance brachial artery endothelial function in this cohort.
- The observed decrease in cutaneous blood flow may relate to the suppression of vasomotor symptoms like hot flashes.
- Results suggest a potential estrogen threshold for achieving vascular benefits, as indicated by low plasma estradiol levels.
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