Basic Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Methodol. Jun 26, 2016; 6(2): 154-162
Published online Jun 26, 2016. doi: 10.5662/wjm.v6.i2.154
Rat model of cholelithiasis with human gallstones implanted in cholestasis-induced virtual gallbladder
Marlein Miranda Cona, Yewei Liu, Ting Yin, Yuanbo Feng, Feng Chen, Stefaan Mulier, Yue Li, Jian Zhang, Raymond Oyen, Yicheng Ni
Marlein Miranda Cona, Yewei Liu, Ting Yin, Yuanbo Feng, Feng Chen, Stefaan Mulier, Raymond Oyen, Yicheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, KU Leuven, 3000 Leuven, Belgium
Stefaan Mulier, Department of Surgery, Leopold Park Clinic, CHIREC Cancer Institute, 1040 Brussels, Belgium
Yue Li, Jian Zhang, Laboratory of Translational Medicine, Jiangsu Province Academy of Traditional Chinese Medicine, Nanjing 210028, Jiangsu Province, China
Author contributions: Miranda Cona M, Liu Y, Yin T, Feng Y, Chen F, Li Y, Zhang J and Ni Y carried out all the experiments, did data analysis and manuscript writing; Mulier S contributed to collecting gallstones from patients, concept designing and manuscript writing; Oyen R contributed to concept designing, technical and financial support, and final approval for submission.
Supported by Flanders Research Foundation (FWO-42865); the KU Leuven Molecular Small Animal Imaging Center MoSAIC (KUL EF/05/08); the center of excellence in vivo molecular imaging research (IMIR); KU Leuven projects IOF-HB/08/009 and IOF-HB/12/018; the European Union (Asia-Link CfP 2006-EuropeAid/123738/C/ACT/Multi-Proposal No. 128-498/111); the National Natural Science Foundation of China No. 81071828; and Jiangsu Province Natural Science Foundation No. BK2010594. The corresponding author is currently a Bayer Lecture Chair holder.
Institutional review board statement: This experimental research was approved by the Ethical Committee of Medical School, KU Leuven, Belgium.
Conflict-of-interest statement: None of the authors have any conflict of interest.
Data sharing statement: No additional data available for this manuscript.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Yicheng Ni, MD, PhD, Professor, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, KU Leuven, Herestraat 49, 3000 Leuven, Belgium. yicheng.ni@med.kuleuven.be
Telephone: +32-16-322752 Fax: +32-16-343765
Received: March 22, 2016
Peer-review started: March 22, 2016
First decision: April 15, 2016
Revised: April 20, 2016
Accepted: May 31, 2016
Article in press: June 2, 2016
Published online: June 26, 2016
Abstract

AIM: To facilitate translational research on cholelithiasis, we have developed a rat model of human gallstones by exploiting the unique biliopancreatic features of this species.

METHODS: Under anesthesia, 16 adult rats of equal genders underwent two times of abdominal surgery. First, their common bile duct (CBD) was ligated to cause cholestasis by total biliary obstruction (TBO). On day 0, 1, 3, 7, 14, 21 and 28 after TBO, magnetic resonance imaging (MRI) was conducted to monitor the dilatation of the CBD, and blood was sampled to analyze total serum bilirubin (TSB). Secondly, on day 30, the abdomen was re-opened and gallstone(s) collected from human patients were implanted in the dilated CBD as a virtual gallbladder (VGB), which was closed by suture ligation. This rat cholelithiasis model was examined by MRI, clinical observation, microcholangiography and histology.

RESULTS: All rats survived two laparotomies. After ligation, the CBD was dilated to a stable size of 4 to 30 mm in diameter on day 21-28, which became a VGB. The rats initially showed signs of jaundice that diminished over time, which paralleled with the evolving TSB levels from 0.6 ± 0.3 mg/dL before ligation, through a peak of 10.9 ± 1.9 mg/dL on day 14, until a nearly normalized value after day 28. The dilated CBD with thickened wall allowed an incision for implantation of human gallstones of 1-10 mm in diameter. The rat cholelithiasis was proven by in vivo MRI and postmortem microcholangiography and histomorphology.

CONCLUSION: A rat model cholelithiasis with human gallstones has been established, which proves feasible, safe, reliable, nontoxic and cost-effective. Given the gallstones of human origin, applications of this model may be of help in translational research such as optical detection and lysis of gallstones by systemic drug administration.

Keywords: Cholelithiasis, Rat, Gallbladder, Common bile duct, Cholestasis, Bilirubin, Gallstones

Core tip: The mouse and rat are common experimental animals. Unlike the mouse that has a gallbladder but difficulty in imaging studies, the rat does not have a gallbladder, which has hampered studies on imaging gallstones. To tackle this problem, we first induced a virtual gallbladder (VGB) in rats by ligation of the common bile duct (CBD) accompanying with gradual increase and normalization of serum bilirubin. Then we implanted gallstone(s) collected from human patients into the dilated CBD or VGB to create a cholelithiatic model in rats, which has been validated by in vivo magnetic resonance imaging, microcholangiography and histology. This rat model is deemed useful for translational research such as fluorescent visualization of gallstones for laparoscopic detection and differential diagnosis of cholelithiasis.