Endothelial Denudation of Isolated Human Internal Mammary Artery Segments
- *Corresponding Author:
- John F Beltrame
Professor of Medicine, Discipline of Medicine
School of Medicine, University of Adelaide
Basil Hetzel Institute for Translational Health Research
The Queen Elizabeth Hospital, 28 Woodville Road
Woodville SA, 5011, Australia
Tel: 61 8 8222 6740
E-mail: [email protected]
Received April 14, 2016; Accepted May 06, 2016; Published May 10, 2016
Citation: Lamin V, Worthington M, Edwards J, Viana F, Stuklis R, et al. (2016) Endothelial Denudation of Isolated Human Internal Mammary Artery Segments. Cardiovasc Pharm Open Access 5: 180. doi:10.4172/2329-6607.1000180
Copyright: © 2016 Lamin V, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Background: Endothelial denudation is an important approach to evaluate the role of the endothelium in vascular reactivity studies. Although approaches to remove the endothelium are well established in animal models, these methods have proved difficult to effectively translate to remnants of human Internal Mammary Artery (IMA) obtained during coronary bypass. This study sought to identify the optimal technique for endothelial denudation of IMA while preserving vascular contractile responses. Methods: IMA segments were subject to endothelial denudation using one of the following techniques: (1) surface abrasion, rubbing with a stainless steel wire, (2) vasoconstriction abrasion or (3) shear abrasion via infusion of an effervescent solution. Following intervention, IMA segments were evaluated by: (1) histochemistry to quantify structural damage and endothelial cell abundance and (2) functional endothelium-dependent vasodilator response using vascular myography in an organ bath preparation. Results: Vasoconstriction abrasion removed endothelial cells and caused disruption of the internal elastic lamina, these vessels failed to respond to the vasoconstrictor Phenylephrine (PE) or the endothelium-dependent vasodilator A23187. Surface abrasion alone was incomplete in removing endothelial cells, vessel vasodilated partially when challenged with A23187 in the presence of PE. Shear abrasion removed endothelial cells most effectively, as these pre-constricted vessels did not relax to A23187 but demonstrated increased sensitivity to PE. Conclusions: In this controlled comparative study assessing both structural and functional endpoints of endothelial denudation techniques, we have demonstrated that shear abrasion by infusion of an effervescent solution is the optimal technique to remove the endothelium and preserve vascular function in human IMA.