Basic Study
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 14, 2024; 30(10): 1420-1430
Published online Mar 14, 2024. doi: 10.3748/wjg.v30.i10.1420
Preliminary exploration of animal models of congenital choledochal cysts
Shu-Hao Zhang, Yue-Bin Zhang, Duo-Te Cai, Tao Pan, Ken Chen, Yi Jin, Wen-Juan Luo, Zong-Wei Huang, Qing-Jiang Chen, Zhi-Gang Gao
Shu-Hao Zhang, Yue-Bin Zhang, Duo-Te Cai, Tao Pan, Ken Chen, Yi Jin, Wen-Juan Luo, Zong-Wei Huang, Qing-Jiang Chen, Zhi-Gang Gao, Department of General Surgery, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou 310000, Zhejiang Province, China
Author contributions: Zhang SH designed and performed the research and wrote the paper; Gao ZG, Zhang YB, and Cai DT designed the research and supervised the report; Chen K, Jin Y, Luo WJ, and Huang ZW designed the research and contributed to the analysis; Chen QJ and Pan T provided clinical advice and supervised the report.
Supported by the Key R&D Program of Zhejiang, No. 2023C03029; Health Science and Technology Plan of Zhejiang Province, No. 2022RC201; and Zhejiang Provincial Natural Science Foundation Project, No. LY20H030007.
Institutional review board statement: The study was reviewed and approved by the Ethics Committee of The Children’s Hospital, Zhejiang University School of Medicine (approval No. 2022-IRB-108). Prior to inclusion in this study, written informed consent was obtained from all subjects.
Institutional animal care and use committee statement: The protocol of the animal study was approved by the Institutional Animal Care and Use Committee of Laboratory Animal Center of Zhejiang University (approval No. ZJU20230273).
Conflict-of-interest statement: The authors declare that they have no conflict of interest.
Data sharing statement: No additional data are available.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Zhi-Gang Gao, PhD, Chief Doctor, Department of General Surgery, Children’s Hospital, Zhejiang University School of Medicine, No. 3333 Binsheng Road, Binjiang District, Hangzhou 310000, Zhejiang Province, China. ebwk@zju.edu.cn
Received: October 17, 2023
Peer-review started: October 17, 2023
First decision: January 15, 2024
Revised: January 17, 2024
Accepted: February 21, 2024
Article in press: February 21, 2024
Published online: March 14, 2024
Abstract
BACKGROUND

Various animal models have been used to explore the pathogenesis of choledochal cysts (CCs), but with little convincing results. Current surgical techniques can achieve satisfactory outcomes for treatment of CCs. Consequently, recent studies have focused more on clinical issues rather than basic research. Therefore, we need appropriate animal models to further basic research.

AIM

To establish an appropriate animal model that may contribute to the investigation of the pathogenesis of CCs.

METHODS

Eighty-four specific pathogen-free female Sprague-Dawley rats were randomly allocated to a surgical group, sham surgical group, or control group. A rat model of CC was established by partial ligation of the bile duct. The reliability of the model was confirmed by measurements of serum biochemical indices, morphology of common bile ducts of the rats as well as molecular biology experiments in rat and human tissues.

RESULTS

Dilation classified as mild (diameter, ≥ 1 mm to < 3 mm), moderate (≥ 3 mm to < 10 mm), and severe (≥ 10 mm) was observed in 17, 17, and 2 rats in the surgical group, respectively, while no dilation was observed in the control and sham surgical groups. Serum levels of alanine aminotransferase, aspartate aminotransferase, total bilirubin, direct bilirubin, and total bile acids were significantly elevated in the surgical group as compared to the control group 7 d after surgery, while direct bilirubin, total bilirubin, and gamma-glutamyltransferase were further increased 14 d after surgery. Most of the biochemical indices gradually decreased to normal ranges 28 d after surgery. The protein expression trend of signal transducer and activator of transcription 3 in rat model was consistent with the human CC tissues.

CONCLUSION

The model of partial ligation of the bile duct of juvenile rats could morphologically simulate the cystic or fusiform CC, which may contribute to investigating the pathogenesis of CC.

Keywords: Choledochal cyst, Animal model, Partial ligation, Cystic and fusiform dilation, Juvenile rats

Core Tip: Recent studies have focused more on clinical issues rather than etiology and pathogenesis of choledochal cyst (CC). In this study, our partial ligation of the bile duct of juvenile rats successfully simulated the pathological processes of recanalization after incomplete obstruction of the distal bile duct. The postoperative disease progression of this model was more consistent with the natural course of CC formation which may assist in further basic research on the pathogenesis of CC.