title: Correlation between Echo-Tracking Parameters and In Vitro Measurements of Arterial Contraction and Relaxation in Rats Fed a High-Cholesterol Diet.
abstract: BACKGROUND
  Echo-tracking (ET) is a new technique that allows the assessment of arterial function and stiffness. This study aimed to ascertain the utility of the echo-tracking (ET) technique to assess vascular stiffness in rats with hypercholesterolemia and atherosclerosis.
  
  
  METHODS
  ET was used to measure the arterial stiffness of the aorta in cholesterol-fed Sprague-Dawley rats (group T1, n=10, for 4 weeks; group T2, n=10, for 12 weeks) and normal control rats (group C1, n=10; group C2, n=10). In vitro isometric tension experiments were used to measure the maximum contractile tension (MCT) and maximum relaxation percentage (MRR%) of aortic rings. Indicators of arterial stiffness and aortic MCT and MRR% were compared between groups using linear regression analysis. Light microscopic evaluation was used to demonstrate atherosclerotic changes in the aorta.
  
  
  RESULTS
  The rat models were successfully induced; pathological examination of the aortas showed significant atherosclerosis in group T2, but not in groups C1, C2, or T1. The arterial stiffness parameters obtained using ET and aortic rings in vitro showed significant impairments in T1 and T2 rats compared with C1 and C2 controls (all P<0.05 vs. controls). In addition, these impairments were greater in the T2 group than in the T1 group (all P<0.05). Finally, MRR% correlated with the distensibility coefficient (r=0.396, P=0.012), arterial compliance (r=0.317, P=0.047), stiffness parameter b (r=-0.406, P=0.009) and one-point pulse wave β (r=-0.434, P=0.005).
  
  
  CONCLUSIONS
  These results suggest that ET could be used to evaluate the changes in arterial wall elasticity associated with atherosclerosis and hypercholesterolemia.
authors.affiliation: Department of Ultrasound, Rui Jin Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Ultrasound, Rui Jin Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Zhan
authors.affiliation: Shanghai Institute of Hypertension, Ruijin Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Yong-Jie
authors.initials: YJ
authors.lastname: Wu
authors.affiliation: Department of Ultrasound, Rui Jin Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Bo
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Shanghai Institute of Hypertension, Ruijin Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Wu-Gang
authors.initials: WG
authors.lastname: Zhou
authors.affiliation: Shanghai Institute of Hypertension, Ruijin Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Dong-Rui
authors.initials: DR
authors.lastname: Chen
authors.affiliation: Department of Ultrasound, Ruijin Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Department of Ultrasound, Ruijin Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Zhen-Hua
authors.initials: ZH
authors.lastname: Liu
authors.affiliation: Department of Pathology, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Jiang
authors.affiliation: Department of Pathology, School of Medicine, Shanghai JiaoTong University, Shanghai, China (mainland).
authors.forename: Lin
authors.initials: L
authors.lastname: Zheng
mesh_terms: D000818:Animals; D001011:Aorta / Q000503:physiopathology; D001012:Aorta, Abdominal / Q000503:physiopathology; D001158:Arteries / Q000503:physiopathology*; D050197:Atherosclerosis / Q000503:physiopathology; D001794:Blood Pressure; D002784:Cholesterol / Q000008:administration & dosage*; D004032:Diet; D004548:Elasticity; D004730:Endothelium, Vascular / Q000000981:diagnostic imaging / Q000503:physiopathology; D006937:Hypercholesterolemia / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D016896:Treatment Outcome; D014463:Ultrasonography / Q000379:methods*; D059289:Vascular Stiffness
chemical_list: D002784:Cholesterol