title: Estrogen replacement attenuates exaggerated neointimal hyperplasia following carotid endarterectomy in rats.
abstract: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Surgery, Division of Vascular Surgery, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
authors.forename: John O
authors.initials: JO
authors.lastname: Nyalala
authors.forename: Aliza T
authors.initials: AT
authors.lastname: Brown
authors.forename: Shaoke
authors.initials: S
authors.lastname: Luo
authors.forename: Hongju
authors.initials: H
authors.lastname: Deng
authors.forename: Mohammed M
authors.initials: MM
authors.lastname: Moursi
mesh_terms: D017130:Angioplasty / Q000009:adverse effects; D000818:Animals; D015415:Biomarkers / Q000097:blood; D020212:Carotid Artery Injuries / Q000097:blood / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D017536:Carotid Artery, Common / Q000187:drug effects* / Q000473:pathology / Q000601:surgery; D016893:Carotid Stenosis / Q000097:blood / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D004195:Disease Models, Animal; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D004958:Estradiol / Q000008:administration & dosage* / Q000097:blood; D015914:Estrogen Replacement Therapy; D005260:Female; D006710:Homocysteine / Q000097:blood; D020138:Hyperhomocysteinemia / Q000097:blood / Q000150:complications; D006965:Hyperplasia; D015918:Infusion Pumps, Implantable; D007601:Jugular Veins / Q000637:transplantation; D010052:Ovariectomy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D017539:Tunica Intima / Q000187:drug effects* / Q000473:pathology / Q000601:surgery
chemical_list: D015415:Biomarkers; D006710:Homocysteine; D004958:Estradiol