title: Effect of isoflavone on balloon catheter-induced neointimal hyperplasia in ovariectomised rabbit carotid artery.
abstract: BACKGROUND
  This study was designed to investigate the effects of phytoestrogen isoflavone on balloon catheter-induced hyperplasia of carotid artery.
  
  
  METHODS
  Forty-eight female New Zealand rabbits were randomly divided into four groups: control (balloon-induced carotid artery injury only); ovariectomy control (ovariectomy and carotid artery injury), oestrogen (ovariectomy, carotid artery injury and nilestriol, 5mg/kg daily for 28 days), and isoflavone (ovariectomy, carotid artery injury and isoflavone 120 mg/kg daily for 28 days). The arterial wall thickness was assessed by coloured ultrasonography, and the oestrogen-α and oestrogen-β receptors in the abdominal aorta were measured by Western blotting.
  
  
  RESULTS
  The medial layer thickness in the isoflavone group was less than in the ovariectomy control group (0.28±0.03 vs. 0.35±0.04 mm, p<0.01), and the intimal/medial layer (I/M) ratio is the isoflavone group was also less than in the ovariectomy control group (16.85±3.79 vs. 48.94±8.92, p<0.01). There was no statistically significant difference in the medial layer thickness or I/M ratio between the isoflavone and the oestrogen groups. The optical density of the oestrogen-α receptors in the isoflavone group (0.317±0.002) was less than in the oestrogen (0.633±0.002) or ovariectomy control group (0.590±0.001, p<0.01). The optical density of the oestrogen-β receptors in the isoflavone group (1.350±0.002) and the ovariectomy control group (1.2033±0.002) was less than in the oestrogen group (1.7699±0.003, p<0.01).
  
  
  CONCLUSIONS
  Isoflavone therapy in the ovariectomised rabbit model attenuated balloon catheter-induced intimal and medial layer hyperplasia in the carotid arteries. Down-regulation of the oestrogen-α receptors may be involved in the hyperplasia-preventative effect.
authors.affiliation: Department of Ultrasound, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, China.
authors.forename: Gai-Ying
authors.initials: GY
authors.lastname: Zhang
authors.affiliation: Department of Ultrasound, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, China. Electronic address: epowerqiu@163.com.
authors.forename: Ren-Feng
authors.initials: RF
authors.lastname: Qiu
authors.affiliation: Department of Ultrasound, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, China.
authors.forename: Ying-Chun
authors.initials: YC
authors.lastname: Sun
authors.affiliation: School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia. Electronic address: lwang@csu.edu.au.
authors.forename: Le-Xin
authors.initials: LX
authors.lastname: Wang
mesh_terms: D000818:Animals; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology*; D002404:Catheterization / Q000009:adverse effects; D029721:Drosophila Proteins / Q000737:chemistry; D047628:Estrogen Receptor alpha / Q000032:analysis; D047629:Estrogen Receptor beta / Q000032:analysis; D005136:Eye Proteins / Q000737:chemistry; D005260:Female; D006965:Hyperplasia / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000209:etiology; D007529:Isoflavones / Q000627:therapeutic use*; D009419:Nerve Tissue Proteins / Q000737:chemistry; D010052:Ovariectomy; D048789:Phytoestrogens / Q000627:therapeutic use*; D011817:Rabbits; D013025:Glycine max; D017539:Tunica Intima / Q000000981:diagnostic imaging / Q000473:pathology*; D018615:Ultrasonography, Doppler, Color
chemical_list: D029721:Drosophila Proteins; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D005136:Eye Proteins; D007529:Isoflavones; D009419:Nerve Tissue Proteins; D048789:Phytoestrogens; C075638:aos protein, Drosophila