Transtail Artery Hepatic Artery Catheterization In Rats Under Direct Vision: A Radiation-Free Method For Establishing Animal Models

Summary

This protocol describes a reproducible open-abdominal trans-caudal-artery chemoembolization technique in rats, enabling precise intra-arterial drug delivery, controlled liver embolization, and standardized assessment of therapeutic and biological responses in liver cancer models.

Abstract

Rat liver tumor models are indispensable for studying trans-arterial chemoembolization (TACE), drug delivery, and tumor biology. However, conventional techniques utilizing fluoroscopy-guided carotid or femoral access are often constrained by high equipment costs, technical complexity, and cumulative radiation risks to operators. This protocol presents a radiation-free alternative using open-laparotomy-guided transtail artery catheterization. We provide a comprehensive, step-by-step description of the procedure, beginning with standardized anesthesia and exposure of the ventral caudal artery (VCA). The core of the technique involves performing a midline laparotomy to enable direct visualization of the hepatoduodenal anatomy, allowing for the precise advancement of a 1.6 Fr microcatheter into the common hepatic artery (CHA) or proper hepatic artery (PHA) using a 0.014-inch microguidewire. Our validation study in 32 rats demonstrates that this method achieves a high technical success rate of 96.9% (31/32) with a mean procedure time of 22.5 ± 2.3 min. This technique provides an accessible, reproducible, and transparent platform for laboratories focusing on localized therapeutic evaluation and embolic biology. This method effectively lowers the barrier for establishing high-quality interventional models in preclinical research environments where advanced imaging is unavailable.

Introduction

Trans-arterial delivery techniques are widely used in preclinical liver cancer research, particularly for modeling trans-arterial chemoembolization (TACE), localized drug delivery, and intra-arterial immunotherapy. However, conventional vascular access routes in rats—including femoral or carotid artery cannulation—are limited by anatomical constraints, vessel fragility, and great technical difficulty, resulting in variability in success rate and reproducibility^1,2,3,4.

The transtail artery approach has....

Protocol

Perform all animal procedures in accordance with the institutional guidelines for the care and use of laboratory animals. Ensure that all surgical and interventional steps comply with approved animal protocols.

1. Anesthesia and preoperative preparation

1. Induce and maintain anesthesia.
   1. Induce anesthesia with 3–5% inhaled isoflurane in an induction chamber.
   2. Administer a maintenance dose of intraperitoneal 1% pentobarbital sodium at 40 mg/kg.
   3. Apply a thin layer of ophthalmic ointment to both eyes to prevent corneal desiccation throughout the surgical procedure.
   <....

Results

The technical efficacy and safety of the radiation-free transtail artery catheterization protocol were evaluated in a validation cohort of 32 rats, with key performance metrics summarized in Table 1. Technical success, defined as stable microcatheter placement in the common hepatic artery (CHA) followed by the unobstructed delivery of embolic materials, was achieved in 31 out of 32 animals (96.9%). The mean procedure time, measured from the initial exposure of the ventral caudal artery (VCA) to final cat.......

Discussion

The rat open-abdomen, trans-tail-artery catheterization method presented here provides a practical and reproducible alternative to traditional TACE models that require fluoroscopic guidance. Several prior studies have established small-animal TACE via the tail artery approaches, typically using DSA to guide catheterization and confirm vascular access^1,2,3,4,5........

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Blunt-tip microforceps (0.4 mm)	Suzhou Shiqiang	11001-12
Curved forceps	Shanghai Medical Instruments (Jinzhong)	S110-3
Heparinized saline injection	Jiangsu Wanbang Biochemical Pharmaceutical Group Co., Ltd.	H32020612
Iodixanol injection	Jiangsu Hengrui Pharmaceuticals Co., Ltd.	H20103675
Isoflurane	RWD Life Science	R510-22
Lidocaine gel	Shandong Fangming Pharmaceutical Group	20180322
Micro-scissors	Shanghai Medical Instruments (Jinzhong)	S320-1
Microcatheter (1.6 Fr)	Cardiolink Science	SS-40-1.6F
Microguidewire (0.014 inch)	Cardiolink Science	PGW14-150A
Needle holder	Shanghai Medical Instruments (Jinzhong)	S201-1
PVA microspheres	Cardiolink Science	VM-20110
Scalpel blade	Shanghai Medical Instruments (Jinzhong)	B102-11
Sodium pentobarbital solution (1%)	Shanghai Pharmaceuticals Holding Co., Ltd.	https://www.sphchina.com/
Straight forceps	Shanghai Medical Instruments (Jinzhong)	S110-1
Straight scissors	Shanghai Medical Instruments (Jinzhong)	S310-1
Suture (4-0) with 3/8-circle needle	Shanghai Jinhuan Medical	J-40-45
Disposable Sterile Syringe (1 mL, 2 mL, 5 mL)	Jiangsu Zhiyu Medical Instrument Co., Ltd.	Z-1022
Toothed forceps	Shanghai Medical Instruments (Jinzhong)	S112-2
Vascular clips	Roboz Surgical Instrument	RS-5420