Implantation of Human-Sized Coronary Stents into Rat Abdominal Aorta Using a Trans-Femoral Access

Summary

This protocol describes the implantation of human coronary stents into the abdominal aorta of rats with an apoE^-/- background using a trans-femoral access. Compared with other animal models, murine models carry the advantages of high throughput, reproducibility, ease of handling and housing, and a broad availability of molecular markers.

Abstract

Percutaneous coronary intervention (PCI), combined with the deployment of a coronary stent, represents the gold standard in interventional treatment of coronary artery disease. In-stent restenosis (ISR) is determined by an excessive proliferation of neointimal tissue within the stent and limits the long-term success of stents. A variety of animal models have been used to elucidate pathophysiological processes underlying in-stent restenosis (ISR), with the porcine coronary and the rabbit iliac artery models being the most frequently used. Murine models provide the advantages of high throughput, ease of handling and housing, reproducibility, and a broad availability of molecular markers. The apolipoprotein E deficient (apoE^-/- ) mouse model has been widely used to study cardiovascular diseases. However, stents must be miniaturized to be implanted into mice, involving important changes of their mechanical and (potentially) biological properties. The use of apoE^-/- rats can overcome these shortcomings as apoE^-/- rats allow for the evaluation of human-sized coronary stents while at the same time providing an atherogenic phenotype. This makes them an excellent and reliable model to investigate ISR after stent implantation. Here, we describe, in detail, the implantation of commercially available human coronary stents into the abdominal aorta of rats with an apoE^-/- background using a trans-femoral access.

Introduction

Percutaneous coronary intervention (PCI), combined with the deployment of a coronary stent, represents the gold standard in interventional treatment of coronary artery disease¹. The long-term success of stents, however, can be limited by the occurrence of in-stent restenosis (ISR) that is determined by an excessive proliferation of neointimal tissue within the stent^2,3. ISR may require a re-intervention either with coronary artery bypass or re-PCI. A variety of animal models have been suggested for the study of ISR, each of them featuring advantages and shortcomings. The major drawbacks....

Protocol

The experiments were performed in accordance with the German animal welfare law (TSchG) and Directive 2010/63/EU pertaining to the protection of animals used for scientific purposes. The official approval for this study was granted by the Governmental Animal Care and Use Committee (Protocol No.: AZ 87-51.04.2010.A065; Landesamt für Natur, Umwelt und Verbraucherschutz Nordrhein-Westfalen, Recklinghausen, Germany). The study protocol complied with the Guide for the Care and Use of Laboratory Animals. Postoperative pai.......

Discussion

This protocol describes the implantation of human-sized coronary stents into the abdominal aorta of apoE^-/- rats. Several technical points are worth emphasizing. First, a mismatch between the stent size and the size of the aorta should be avoided. Placing too small a stent can lead to stent malapposition, whereas implantation of a stent that is too large for the aorta can cause overstretch, tearing, and injury of the vessel. Therefore, we recommend using stents between 2.0 and 2.5 mm in diameter, and to keep i.......

Materials

Name	Company	Catalog Number	Comments
Diet
SNIFF High Fat diet + Clopidogrel (15 mg/kg)	SNIFF Spezialdiäten GmbH, Soest	custom prepared	Western Diet
Drugs and Anesthetics
Buprenorphine	Essex Pharma	997.00.00
ISOFLO (Isoflurane Vapor) vaporiser	Eickemeyer	4802885
Isoflurane	Forene Abbott	B 506
Isotonic (0.9%) NaCl solution	DeltaSelect GmbH	PZN 00765145
Ringer's lactate solution	Baxter Deutschland GmbH	3775380
(S)-ketamine	CEVA Germany
Xylazine	Medistar Germany
Consumable supplies
10 mL syringes	BD Plastipak	4606108V
2 mL syringes	BD Plastipak	4606027V
6-0 prolene suture	ETHICON	N-2719K
4-0 silk suture	Seraflex	IC 158000
Bepanthen Eye and Nose Ointment	Bayer Vital GmbH	6029009.00.00
Cotton Gauze swabs	Fuhrmann GmbH	32014
Durapore silk tape	3M	1538-1
Poly-Alcohol Skin Desinfection Solution	Antiseptica GmbH	72PAH200
Sterican needle 18 G	B. Braun	304622
Sterican needle 27 3/4 G	B.Braun	4657705
Tissue Paper	commercially available
Surgical instruments
Graefe forceps curved x1	Fine Science Tools Inc.	11151-10
Graefe forceps straight	Fine Science Tools Inc.	11050-10
Needle holder Mathieu	Fine Science Tools Inc.	12010-14
Scissors	Fine Science Tools Inc.	14074-11
Semken forceps	Fine Science Tools Inc.	11008-13
Small surgical scissors curved	Fine Science Tools Inc.	14029-10
Small surgical scissors straight	Fine Science Tools Inc.	14028-10
Standard pattern forceps	Fine Science Tools Inc.	11000-12
Vannas spring scissors	Fine Science Tools Inc.	15000-08
Equipment
Dissecting microscope	Leica MZ9
Temperature controlled heating pad	Sygonix	26857617
Equipment for stent implantation
Drug-eluting stent Xience 2,25mm x 8mm	Abbott Vascular USA	1009544-18
Guide wire Fielder XT PTCA guide wire: 0.014" x 300cm	ASAHI INTECC CO., LTD Japan	AGP140302
Inflation syringe system	Abbott 20/30 Priority Pack	1000186
Tissue processing and analysis
30% H2O2	Roth	9681	Histology
Ethanol	Roth	K928.1	Histology
Giemsas Azur-Eosin-Methylenblau	Merck	109204	Histology
Graphic Drawing Tablet	WACOM Europe GmbH	CTL-6100WLK-S
Roti Histofix, Formaldehyd 4% buffered	Roth	P087	Histology
Technovit 9100	Morphisto	12225.K1000	Histology