title: Magnetic resonance imaging characteristics of hepatocyte apoptosis (induced by right portal vein ligation) and necrosis (induced by combined right portal vein and right hepatic artery ligation) in rats.
abstract: OBJECTIVE
  Using magnetic resonance imaging (MRI), this study aimed to demonstrate the appearance of hepatocytes following ligation of the right portal vein or combined ligation of the right portal vein and right hepatic artery, in a rat model.
  
  
  METHODS
  Ninety adult Sprague-Dawley rats (body weight 250-300 g) were divided into three groups (n = 30 per group): ligation of the right portal vein (Group A); combined ligation of the right portal vein and right hepatic artery (Group B); no intervention to obstruct blood supply (control group). Rats were then randomly subdivided into five groups that underwent examination at 3 h and 1, 3, 7 and 14 days postprocedure (n = 6 per group). Livers were examined by routine MRI, diffusion-weighted imaging (DWI) and magnetic resonance spectroscopy (MRS). After examination, each group of rats was sacrificed. Right hepatic lobes were removed and examined by pathology in six rats per timepoint; transmission electron microscopy (TEM) was undertaken in up to three rats per timepoint.
  
  
  RESULTS
  Hepatocyte apoptosis and necrosis, by right portal vein ligation and combined right portal vein and right hepatic artery ligation respectively, were confirmed by pathology and TEM. In Group A, there were slight increases in intensity of T1- and T2-weighted images and in the apparent diffusion coefficient (ADC). In addition there were larger areas under the lactic acid and lipid peaks on MRS. In Group B, there were increased T1 and T2 signals, a decrease in the ADC and an increase of the area under the lactic acid peaks on MRS.
  
  
  CONCLUSIONS
  Hepatocyte apoptosis and necrosis induced by ligation procedures exhibited specific changes that were evident on MRI, DWI and MRS, and could be detected in vivo by MRI, in a rat model.
authors.affiliation: Department of Radiology, Shanghai Pudong New Area Gongli Hospital, Shanghai, China.
authors.forename: Bingcang
authors.initials: B
authors.lastname: Huang
authors.affiliation: Department of Radiology, Huashan Hospital, Fudan University, Shanghai, China.
authors.forename: Daoying
authors.initials: D
authors.lastname: Geng
authors.affiliation: Department of Radiology, Shanghai Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China hbc9209@163.com.
authors.forename: Songhua
authors.initials: S
authors.lastname: Zhan
authors.affiliation: Department of Radiology, Shanghai Pudong New Area Gongli Hospital, Shanghai, China.
authors.forename: Huanhuan
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Radiology, Shanghai Pudong New Area Gongli Hospital, Shanghai, China.
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Radiology, Shanghai Pudong New Area Gongli Hospital, Shanghai, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Yi
mesh_terms: D000818:Animals; D017209:Apoptosis; D004058:Diffusion; D006499:Hepatic Artery / Q000601:surgery*; D022781:Hepatocytes / Q000473:pathology*; D008026:Ligation; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009336:Necrosis; D011169:Portal Vein / Q000601:surgery*; D017207:Rats, Sprague-Dawley; D012815:Signal Processing, Computer-Assisted
keywords: Magnetic resonance imaging; apoptosis; hepatocyte; ligation; necrosis; rat