Related Experiment Video
Updated: May 25, 2026
A Rat Carotid Artery Pressure-Controlled Segmental Balloon Injury with Periadventitial Therapeutic Application
Published on: July 9, 2020
Estrogen replacement attenuates exaggerated neointimal hyperplasia following carotid endarterectomy in rats
John O Nyalala1, Aliza T Brown, Shaoke Luo
1Department of Surgery, Division of Vascular Surgery, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Background:
To investigate whether estrogen may attenuate neointima formation in hyperhomocysteinemic rat carotid endarterectomy.
Methods:
Rats were divided into 6 groups: ovariectomized estradiol-treated homocysteine or chow; ovariectomized placebo-treated homocysteine or chow; intact placebo-treated homocysteine or chow. Chow served as controls while homocysteine served as exaggerated intimal hyperplasia. Prior to endarterectomy, rats were implanted with estradiol mini-pump or placebo, diets given 2 weeks before and after surgery. Homocysteine, estrogen, and neointimal hyperplasia were determined.
Results:
Homocysteine was elevated in homocysteine groups versus controls except in estradiol-treated group. Intimal hyperplasia increased in placebo-treated ovariectomized homocysteine versus intact group. Exaggerated intimal hyperplasia in placebo-treated ovariectomized homocysteine was reduced by estrogen and so was homocysteine. Estrogen replacement in ovariectomized homocysteine group reduced intimal hyperplasia to that of intact or ovariectomized controls.
Conclusion:
Estradiol treatment in this ovariectomized hyperhomocysteinemia carotid endarterectomy and resultant attenuation of homocysteine and neointima may have relevance to the beneficial effects of estrogen on hyperplastic response.
