Research

Hormonal

Conjugated equine estrogens (CEE) are less effective than endogenous estradiol at inhibiting smooth muscle cell growth and preventing neointima formation due to lower binding affinity and potency at estrogen receptors.

Not all estrogens are equal. CEE, commonly used in HRT, contains weaker estrogens (estrone, estriol) that are less potent at blocking vascular remodeling than pure estradiol. This pharmacological difference may explain why CEE trials failed to show heart benefits while estradiol trials showed some vascular improvement.

GoodRefutesHIGH confidence
In in vitro studies using human aortic SMCs, we demonstrated that in contrast to estradiol, estrone, estriol, estrone sulfate (major components of CEEs) were less potent in inhibiting mitogen-induced SMC growth and mitogen-activated protein kinase activity.
Raghvendra K. Dubey et al. · Cardiovascular Research · 2005

Why this rating

Supported by in vitro studies and non-human primate models cited in the review.

Source

Vascular consequences of menopause and hormone therapy: Importance of timing of treatment and type of estrogen

Raghvendra K. Dubey et al. · Cardiovascular Research · 2005

DOI 10.1016/j.cardiores.2004.12.012

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DOI resolved against Crossref · corpus check 2026-06-10

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