title: The role of estrogen in the formation of experimental abdominal aortic aneurysm.
abstract: OBJECTIVE
  The current study sought to investigate the role of estrogen in the formation of experimental abdominal aortic aneurysm (AAA).
  
  
  METHODS
  Elastase perfusion of infrarenal AAA animal model was performed in 20 female and 20 male Wistar rats that were randomly divided into an ovariectomized/sham-operated group and an estradiol (E2) experimental/saline control group, respectively. At day 14, E2 was detected, while the mRNA and protein expressions of matrix metalloproteinases 2 and 9 (MMP-2 and -9) in AAA tissue were detected by immunohistochemistry and polymerase chain reaction (PCR).
  
  
  RESULTS
  The ovariectomized group showed lower estrogen levels and a higher aneurysm dilatation rate and significantly higher MMP-2 and -9 expression compared with the sham-operated group (P < .01), which was in accordance with MMP-2 and -9 mRNA expression. The E2 group showed higher estrogen levels and a lower aneurysm dilatation rate and significantly lower MMP-2 and -9 expression than did the saline control group (P < .01), which was in accordance with MMP-2 and -9 mRNA expression.
  
  
  CONCLUSIONS
  In the pathogenesis of AAA, estrogen may play an inhibitory role by decreasing expression of MMP-2 and MMP-9 synthesis.
authors.affiliation: Third General Surgery Department, Affiliated ZhongShan Hospital, DaLian University, DaLian 116001, China. wxf2004103@yahoo.com.cn
authors.forename: Xiao-Fei
authors.initials: XF
authors.lastname: Wu
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Saulius
authors.initials: S
authors.lastname: Paskauskas
authors.forename: Shi-Jie
authors.initials: SJ
authors.lastname: Xin
authors.forename: Zhi-Quan
authors.initials: ZQ
authors.lastname: Duan
mesh_terms: D000818:Animals; D017544:Aortic Aneurysm, Abdominal / Q000209:etiology*; D004195:Disease Models, Animal; D004967:Estrogens / Q000502:physiology*; D005260:Female; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004967:Estrogens