Isolation and Excision of Murine Aorta; A Versatile Technique in the Study of Cardiovascular Disease

Summary

Pathology of the aorta can lead to severe morbidity and mortality, therefore research of disease progression and potential therapies is warranted. Here, we present a protocol to isolate and excise the murine aorta to aid researchers in their investigation of cardiovascular disease.

Abstract

Cardiovascular disease is a broad term describing disease of the heart and/or blood vessels. The main blood vessel supplying the body with oxygenated blood is the aorta. The aorta may become affected in diseases such as atherosclerosis and aneurysm. Researchers investigating these diseases would benefit from direct observation of the aorta to characterize disease progression as well as to evaluate efficacy of potential therapeutics. The goal of this protocol is to describe proper isolation and excision of the aorta to aid investigators researching cardiovascular disease. Isolation and excision of the aorta allows investigators to look at gross morphometric changes as wells as allowing them to preserve and stain the tissue to look at histologic changes if desired. The aorta may be used for molecular studies to evaluate protein and gene expression to discover targets of interest and mechanisms of action. This technique is superior to imaging modalities as they have inherent limitations in technology and cost. Additionally, primary isolated cells from a freshly isolated and excised aorta can allowing researchers to perform further in situ and in vitro assays. The isolation and excision of the aorta has the limitation of having to sacrifice the animal however, in this case the benefits outweigh the harm as it is the most versatile technique in the study of aortic disease.

Introduction

The aorta plays a pivotal role in cardiovascular function supplying the body with oxygenated blood and similar to others portions of the body, is susceptible to disease. Common aortic diseases include atherosclerosis and aneurysm, which are the results of genetic and environmental factors including diet, smoking and sedentary lifestyle¹. Atherosclerosis is the deposition of a calcium- and lipid-based plaque to the aortic wall typically found in patients with chronic hyperlipidemia². Aneurysms are characterized by degradation of the structural components of the aorta and thinning of the vessel wall, followed by an increased diameter which could ul....

Protocol

All animal procedures were performed with the approval of the Institutional Animal Care and Use Committee of the University of Cincinnati and in accordance with the Guide for the Care and Use of Laboratory Animals from the National Institutes of Health (NIH Publication No. 85-23, Revised 1996).

1. Preparing the Mouse

1. Euthanize by exposing the animal to a supratherapeutic dose of anesthetic, isoflurane inhaled to effect. Verify primary euthanasia via toe pinch as a noxious stimulus. Secondary method of euthanasia, diaphragm cutting, will occur in an upcoming step. Alternative methods may be used granted euthanasia is obtained.

Results

Upon completion of the procedure, there will be an intact aorta originating from the heart, descending into the thoracic and abdominal cavities with the renal arteries still attached (Figure 1A). From here, the aorta can be imaged in situ to quantify morphometric changes which are diagnostic in the study of abdominal aortic aneurysms (Figure 1B and 1C). Subsequently, the aorta can be removed, fixed and stained to look at histological changes. A general and commo.......

Discussion

Aortic disease can lead to significant systemic pathology and possibly death in severe cases. Treatment options are currently limited therefore continued research in the field is necessary¹⁰. Murine models are ideal to further study disease progression and potentially therapeutic options⁴. Therefore, the successful completion of the method described in this manuscript will provide investigators with the tools to measure disease progression and drug efficacy.

This techniq.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Isoflurane	Med-Vet International	#RXISO-250
70% ethanol	Fisher	07-678-001
Phosphate buffered saline	Sigma Aldrich	P5368-10PAK
Surgical tape	3M	1527-1
Sterile gauze	Dukal Corporations	1312
25 gauge needle	BD	305122
10 ml syringe	BD	309604