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Updated: Jun 16, 2026
An In Vivo Estrogen Deficiency Mouse Model for Screening Exogenous Estrogen Treatments of Cardiovascular Dysfunction After Menopause
Published on: August 13, 2019
Plasma orexin-A levels in postmenopausal women: possible interaction with estrogen and correlation with
M Sh E A El-Sedeek1, A A Korish, M M Deef
1Department of Obstetrics and Gynaecology, Faculty of Medicine, Alexandria University, Alexandria, Egypt. mervatsheikhelarab@yahoo.com
Objective:
To assess plasma orexin-A levels in a group of postmenopausal women not receiving estrogen-replacement therapy (ERT), and to compare the values with a group on ERT and a group of reproductive-age women, and to correlate the findings with some cardiovascular risk factors.
Design:
Observational cohort study.
Setting:
Alexandria University Hospital.
Population:
Ninety women, in three groups: a control group of 30 healthy, reproductive-age women, 30 healthy postmenopausal women not receiving ERT, and 30 healthy postmenopausal women on ERT for 6 months.
Methods:
Quantitative clinical assessment as well as laboratory investigations.
Main Outcome Measures:
Orexin-A levels, serum estradiol, cholesterol, triglycerides, and fasting glucose are the main laboratory outcome measures, whereas blood pressure and weight are the main clinical outcome measures.
Results:
Postmenopausal women not receiving ERT had the highest levels of plasma orexin A (705.61 +/- 165.62 microg/dl). Postmenopausal women on ERT had orexin-A levels that were comparable with the control group (233.90 +/- 54.26 versus 243.81 +/- 68.88 microg/dl). Plasma orexin-A levels were directly correlated with blood glucose lipid profile, arterial blood pressure, and body mass index.
Conclusions:
Higher orexin-A levels are associated with hypoestrogenism, and are partially reversed by ERT. A possible inhibitory effect of estrogen on orexin might partially account for its cardioprotective effect.
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