N.E.B. was supported by a training grant from the National Institute of Environmental Health Sciences (5T32ES007126-35, 2018), and an American Heart Association pre-doctoral fellowship (20PRE35120321). E.S.M.B. was a KL2 scholar partially supported by the UNC Clinical and Translational Science Award-K12 Scholars Program (KL2TR002490, 2018), and the National Heart, Lung, and Blood Institute (K01HL145354). The authors thank Dr. Pablo Ariel of the UNC Microscopy Services Laboratory for assisting with LSFM. Light Sheet Fluorescence Microscopy was performed at the Microscopy Services Laboratory. The Microscopy Services Laboratory, Department of Pathology and Laboratory Medicine, is supported in part by P30 CA016086 Cancer Center Core Support Grant to the UNC Lineberger Comprehensive Cancer Center.

All methods described here have been approved by the Institutional Animal Care and Use Committee (IACUC) of the University of North Carolina at Chapel Hill.
1. Preoperative procedures
<ol>
	<li>Sterilize surgical instruments. Autoclave all surgical instruments before surgery. If performing multiple surgeries on the same day, sterilize instruments between surgeries using a dry bead sterilizer.</li>
	<li>Prepare therapeutic in 25% Pluronic-127 gel (diluted in sterile distilled water).</li>
	<l...

<ol>
	<li>American Heart Association. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiovascular+Disease:+A+Costly+Burden+for+America,+Projections+Through+2035.">Cardiovascular Disease: A Costly Burden for America, Projections Through 2035.</a> American Heart Association CVD Burden Report. , (2017).</li><li>Singh, R. B., Mengi, S. A., Xu, Y. J., Arneja, A. S., Dhalla, N. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogenesis+of+atherosclerosis:+A+multifactorial+process.">Pathogenesis of atherosclerosis: A multifactorial process.</a> Experimental and Clinical Cardiology. 7 (1), 40-53 (2002).</li><li>Clowes, A. W., Reidy, M. A., Clowes, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+of+stenosis+after+arterial+injury.">Mechanisms of stenosis after arterial injury.</a> Laboratory Investigation. 49 (2), 208-215 (1983).</li><li>Clowes, A. W., Reidy, M. A., Clowes, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetics+of+cellular+proliferation+after+arterial+injury.+I.+Smooth+muscle+growth+in+the+absence+of+endothelium.">Kinetics of cellular proliferation after arterial injury. I. Smooth muscle growth in the absence of endothelium.</a> Laboratory Investigation. 49 (3), 327-333 (1983).</li><li>Sartore, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contribution+of+adventitial+fibroblasts+to+neointima+formation+and+vascular+remodeling:+from+innocent+bystander+to+active+participant.">Contribution of adventitial fibroblasts to neointima formation and vascular remodeling: from innocent bystander to active participant.</a> Circulation Research. 89 (12), 1111-1121 (2001).</li><li>Tanaka, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circulating+progenitor+cells+contribute+to+neointimal+formation+in+nonirradiated+chimeric+mice.">Circulating progenitor cells contribute to neointimal formation in nonirradiated chimeric mice.</a> The FASEB Journal. 22 (2), 428-436 (2008).</li><li>Henry, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carotid+angioplasty+and+stenting+under+protection.+Techniques,+results+and+limitations.">Carotid angioplasty and stenting under protection. Techniques, results and limitations.</a> The Journal of Cardiovascular Surgery. 47 (5), 519-546 (2006).</li><li>Kounis, N. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thrombotic+responses+to+coronary+stents,+bioresorbable+scaffolds+and+the+Kounis+hypersensitivity-associated+acute+thrombotic+syndrome.">Thrombotic responses to coronary stents, bioresorbable scaffolds and the Kounis hypersensitivity-associated acute thrombotic syndrome.</a> Journal of Thoracic Disease. 9 (4), 1155-1164 (2017).</li><li>Jackson, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+of+restenosis.">Animal models of restenosis.</a> Trends in Cardiovascular Medicine. 4 (3), 122-130 (1994).</li><li>Shears, L. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+inhibition+of+intimal+hyperplasia+by+adenovirus-mediated+inducible+nitric+oxide+synthase+gene+transfer+to+rats+and+pigs+in+vivo.">Efficient inhibition of intimal hyperplasia by adenovirus-mediated inducible nitric oxide synthase gene transfer to rats and pigs in vivo.</a> Journal of the American College of Surgeons. 187 (3), 295-306 (1998).</li><li>Takayama, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+murine+model+of+arterial+restenosis:+technical+aspects+of+femoral+wire+injury.">A murine model of arterial restenosis: technical aspects of femoral wire injury.</a> Journal of Visualized Experiments. (97), (2015).</li><li>Zhang, L. N., Parkinson, J. F., Haskell, C., Wang, Y. X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+of+intimal+hyperplasia+learned+from+a+murine+carotid+artery+ligation+model.">Mechanisms of intimal hyperplasia learned from a murine carotid artery ligation model.</a> Current Vascular Pharmacology. 6 (1), 37-43 (2008).</li><li>Jahnke, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+a+new+double-injury+restenosis+model+in+the+rat+aorta.">Characterization of a new double-injury restenosis model in the rat aorta.</a> Journal of Endovascular Therapy. 12 (3), 318-331 (2005).</li><li>Gregory, E. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Periadventitial+atRA+citrate-based+polyester+membranes+reduce+neointimal+hyperplasia+and+restenosis+after+carotid+injury+in+rats.">Periadventitial atRA citrate-based polyester membranes reduce neointimal hyperplasia and restenosis after carotid injury in rats.</a> American Journal of Physiology-Heart and Circulatory Physiology. 307 (10), 1419-1429 (2014).</li><li>Buglak, N. E., Jiang, W., Bahnson, E. S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cinnamic+aldehyde+inhibits+vascular+smooth+muscle+cell+proliferation+and+neointimal+hyperplasia+in+Zucker+Diabetic+Fatty+rats.">Cinnamic aldehyde inhibits vascular smooth muscle cell proliferation and neointimal hyperplasia in Zucker Diabetic Fatty rats.</a> Redox Biology. 19, 166-178 (2018).</li><li>Bahnson, E. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+effect+of+PROLI/NO+on+cellular+proliferation+and+phenotype+after+arterial+injury.">Long-term effect of PROLI/NO on cellular proliferation and phenotype after arterial injury.</a> Free Radical Biology and Medicine. 90, 272-286 (2016).</li><li>Gilbert, J. C. W., Davies, M. C., Hadgraft, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+behaviour+of+Pluronic+F127+in+aqueous+solution+studied+using+fluorescent+probes.">The behaviour of Pluronic F127 in aqueous solution studied using fluorescent probes.</a> International Journal of Pharmaceutics. 40 (1-2), 93-99 (1987).</li><li>Tulis, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Histological+and+morphometric+analyses+for+rat+carotid+balloon+injury+model.">Histological and morphometric analyses for rat carotid balloon injury model.</a> Methods in Molecular Medicine. 139, 31-66 (2007).</li><li>Buglak, N. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light+Sheet+Fluorescence+Microscopy+as+a+New+Method+for+Unbiased+Three-Dimensional+Analysis+of+Vascular+Injury.">Light Sheet Fluorescence Microscopy as a New Method for Unbiased Three-Dimensional Analysis of Vascular Injury.</a> Cardiovascular Research. , (2020).</li><li>Renier, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=iDISCO:+a+simple,+rapid+method+to+immunolabel+large+tissue+samples+for+volume+imaging.">iDISCO: a simple, rapid method to immunolabel large tissue samples for volume imaging.</a> Cell. 159 (4), 896-910 (2014).</li><li>Ariel, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> UltraMicroscope II - A User Guide. , (2018).</li><li>Touchard, A. G., Schwartz, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preclinical+restenosis+models:+challenges+and+successes.">Preclinical restenosis models: challenges and successes.</a> Toxicologic Pathology. 34 (1), 11-18 (2006).</li><li>Xiangdong, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+for+the+atherosclerosis+research:+a+review.">Animal models for the atherosclerosis research: a review.</a> Protein Cell. 2 (3), 189-201 (2011).</li><li>Chen, H., Li, D., Liu, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+Rat+Models+for+Atherosclerosis.">Novel Rat Models for Atherosclerosis.</a> Journal of Cardiology and Cardiovascular Sceinces. 2 (2), 29-33 (2018).</li><li>Xing, D., Nozell, S., Chen, Y. F., Hage, F., Oparil, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estrogen+and+mechanisms+of+vascular+protection.">Estrogen and mechanisms of vascular protection.</a> Arteriosclerosis, Thrombosis, and Vascular Biology. 29 (3), 289-295 (2009).</li><li>Tulis, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rat+carotid+artery+balloon+injury+model.">Rat carotid artery balloon injury model.</a> Methods in Molecular Medicine. 139, 1-30 (2007).</li><li>Pellet-Many, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuropilins+1+and+2+mediate+neointimal+hyperplasia+and+re-endothelialization+following+arterial+injury.">Neuropilins 1 and 2 mediate neointimal hyperplasia and re-endothelialization following arterial injury.</a> Cardiovascular Research. 108 (2), 288-298 (2015).</li><li>Wu, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perivascular+delivery+of+resolvin+D1+inhibits+neointimal+hyperplasia+in+a+rat+model+of+arterial+injury.">Perivascular delivery of resolvin D1 inhibits neointimal hyperplasia in a rat model of arterial injury.</a> Journal of Vascular Surgery. 65 (1), 207-217 (2017).</li><li>Tan, J., Yang, L., Liu, C., Yan, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MicroRNA-26a+targets+MAPK6+to+inhibit+smooth+muscle+cell+proliferation+and+vein+graft+neointimal+hyperplasia.">MicroRNA-26a targets MAPK6 to inhibit smooth muscle cell proliferation and vein graft neointimal hyperplasia.</a> Scientific Reports. 7, 46602 (2017).</li><li>Pearce, C. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beneficial+effect+of+a+short-acting+NO+donor+for+the+prevention+of+neointimal+hyperplasia.">Beneficial effect of a short-acting NO donor for the prevention of neointimal hyperplasia.</a> Free Radical Biology and Medicine. 44 (1), 73-81 (2008).</li><li>Cao, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=S100B+promotes+injury-induced+vascular+remodeling+through+modulating+smooth+muscle+phenotype.">S100B promotes injury-induced vascular remodeling through modulating smooth muscle phenotype.</a> Biochimica et Biophysica Acta - Molecular Basis of Disease. 1863 (11), 2772-2782 (2017).</li><li>Madigan, M., Entabi, F., Zuckerbraun, B., Loughran, P., Tzeng, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Delayed+inhaled+carbon+monoxide+mediates+the+regression+of+established+neointimal+lesions.">Delayed inhaled carbon monoxide mediates the regression of established neointimal lesions.</a> Journal of Vascular Surgery. 61 (4), 1026-1033 (2015).</li><li>Khurana, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Angiogenesis-dependent+and+independent+phases+of+intimal+hyperplasia.">Angiogenesis-dependent and independent phases of intimal hyperplasia.</a> Circulation. 110 (16), 2436-2443 (2004).</li><li>Tsihlis, N. D., Vavra, A. K., Martinez, J., Lee, V. R., Kibbe, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nitric+oxide+is+less+effective+at+inhibiting+neointimal+hyperplasia+in+spontaneously+hypertensive+rats.">Nitric oxide is less effective at inhibiting neointimal hyperplasia in spontaneously hypertensive rats.</a> Nitric Oxide. 35, 165-174 (2013).</li><li>Chen, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+neointimal+hyperplasia+in+the+rat+carotid+artery+injury+model+by+a+HMGB1+inhibitor.">Inhibition of neointimal hyperplasia in the rat carotid artery injury model by a HMGB1 inhibitor.</a> Atherosclerosis. 224 (2), 332-339 (2012).</li><li>Mano, T., Luo, Z., Malendowicz, S. L., Evans, T., Walsh, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reversal+of+GATA-6+downregulation+promotes+smooth+muscle+differentiation+and+inhibits+intimal+hyperplasia+in+balloon-injured+rat+carotid+artery.">Reversal of GATA-6 downregulation promotes smooth muscle differentiation and inhibits intimal hyperplasia in balloon-injured rat carotid artery.</a> Circulation Research. 84 (6), 647-654 (1999).</li><li>Becher, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-Dimensional+Imaging+Provides+Detailed+Atherosclerotic+Plaque+Morphology+and+Reveals+Angiogenesis+after+Carotid+Artery+Ligation.">Three-Dimensional Imaging Provides Detailed Atherosclerotic Plaque Morphology and Reveals Angiogenesis after Carotid Artery Ligation.</a> Circulation Research. 126 (5), 619-632 (2020).</li></ol>

The authors declare that there are no conflicts of interest regarding the publication of this manuscript.

The rat carotid artery balloon injury is one of the most extensively used and studied restenosis animal models. Both the original balloon injury model3 and the modified pressure-controlled segmental injury variation10 have informed many aspects of the arterial injury response that also occurs in humans, with the few limitations being that fibrin-rich thrombus rarely develops and local inflammation is minimal compared to other injury models such as in hypercholesterolemic ra...

Cardiovascular disease (CVD) remains the leading cause of death worldwide1. Atherosclerosis is the underlying cause of most CVD-related morbidity and mortality. Atherosclerosis is the build-up of plaque inside arteries that results in a narrowed lumen, hindering proper blood perfusion to organs and distal tissues2. Clinical interventions for treating severe atherosclerosis include balloon angioplasty with or without stent placement. This intervention involves advancing a balloon catheter to the site of plaque, and inflating the balloon to compress the plaque to the arterial wall, widening the luminal area. This procedure damages the artery, however, initiating the arterial injury response3. Prolonged activation of this injury response leads to arterial restenosis, or re-narrowing, secondary to neointimal hyperplasia and vessel remodeling. During angioplasty the intimal layer is denuded of endothelial cells leading to immediate platelet recruitment and local inflammation. Local signaling induces phenotypic changes in vascular smooth muscle cells (VSMC) and adventitial fibroblasts. This leads to the migration and proliferation of VSMC and fibroblasts inwards to the lumen, leading to neointimal hyperplasia4,5. Circulating progenitor cells and immune cells also contribute to the overall volume of restenosis6. Where applicable, drug-eluting stents (DES) are the current standard for inhibiting restenosis7. DES inhibit arterial re-endothelialization, however, thus creating a pro-thrombotic environment that can result in late in-stent thrombosis8. Therefore, animal models are integral for both understanding the pathophysiology of restenosis, and for developing better therapeutic strategies to prolong the efficacy of revascularization procedures.
Several large and small animal models9 are utilized for studying this pathology. These include balloon-injury3,10 or wire-injury11 of the luminal side of an artery, as well as partial ligation12 or cuff placement13 around the artery. The balloon and wire injury both denude the endothelial layer of the artery, mimicking what occurs clinically after angioplasty. In particular, balloon-injury models utilize similar tools as in the clinical setting (i.e., balloon catheter). The balloon injury is best performed in rat models, as rat arteries are an appropriate size for commercially available balloon catheters. Herein we describe a pressure-controlled segmental arterial injury, a well-established, modified version of the rat carotid artery balloon injury. This pressure-controlled approach closely mimics the clinical angioplasty procedure, and allows for reproducible neointimal hyperplasia formation two weeks after injury14,15. Additionally, this pressure-controlled arterial injury results in complete endothelial layer restoration by 2 weeks after surgery16. This directly contrasts the original balloon injury model, described by Clowes, where the endothelial layer never returns to full coverage3.
After surgery, therapeutics may be applied to or directed towards the injured artery through several approaches. The method described herein uses periadventitial application of a small molecule embedded in a Pluronic gel solution. Specifically, we apply a solution of 100 &#956;M cinnamic aldehyde in 25% Pluronic-F127 gel to the artery immediately after injury to inhibit neointimal hyperplasia formation15. Pluronic-F127 is a non-toxic, thermo-reversible gel able to deliver drugs locally in a controlled manner17. Meanwhile, arterial injury is local, hence local administration allows for testing an active principle while minimizing off-target effects. Nevertheless, effective delivery of a therapeutic using this method will depend on the chemistry of the small molecule or biologic used.

<table border="0" cellpadding="0" cellspacing="0" style="width:776px;" width="776">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:327px;">1 mL Syringe</td>
			<td style="width:148px;">Fisher</td>
			<td style="width:119px;">14955450</td>
			<td style="width:183px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1 mL Syringe with needle</td>
			<td style="width:148px;">BD</td>
			<td style="width:119px;">309626</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2 French Fogarty Balloon Embolectomy Catheter</td>
			<td style="width:148px;">Edwards LifeSciences</td>
			<td style="width:119px;">120602F</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">4-0 Ethilon (Nylon) Suture</td>
			<td style="width:148px;">Ethicon Inc</td>
			<td style="width:119px;">662H</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">4-0 Vicryl Suture</td>
			<td style="width:148px;">Ethicon Inc</td>
			<td style="width:119px;">J214H</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">7-0 Prolene Suture</td>
			<td style="width:148px;">Ethicon Inc</td>
			<td style="width:119px;">8800H</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">70% ethyl alcohol</td>
			<td style="width:148px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:327px;">Anti-Rabbit Alexa Fluor 647</td>
			<td style="width:148px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">A21245</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Atropine Sulfate</td>
			<td style="width:148px;">Vedco Inc</td>
			<td style="width:119px;"></td>
			<td>for veterinary use</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cotton Swabs</td>
			<td style="width:148px;">Puritan</td>
			<td style="width:119px;">806-WC</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Curved Hemostats</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">13009-12</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fine Curved Forceps</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">11203-25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fine Scissors</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">14090-11</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Gauze</td>
			<td style="width:148px;">Covidien</td>
			<td style="width:119px;">2252</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:327px;">IHC-Tek Diluent (pH 7.4)</td>
			<td style="width:148px;">IHC World</td>
			<td style="width:119px;">IW-1000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Insufflator</td>
			<td style="width:148px;">Merit Medical</td>
			<td style="width:119px;">IN4130</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Iodine solution</td>
			<td style="width:148px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Lubricating Eye Ointment</td>
			<td style="width:148px;">Dechra</td>
			<td style="width:119px;"></td>
			<td>for veterinary use</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mayo Scissors</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">14010-15</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Micro Serrefines</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">18055-05</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microdissection Scissors</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">15004-08</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Micro-Serrefine Clamp Applying Forceps</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">18057-14</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Needle Holder</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">12003-15</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Pluronic-127 (diluted in sterile water)</td>
			<td style="width:148px;">Sigma-Aldrich</td>
			<td style="width:119px;">P2443</td>
			<td style="width:183px;">25% prepared</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:327px;">Rabbit Anti-CD31</td>
			<td style="width:148px;">Abcam</td>
			<td style="width:119px;">ab28364</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Retractor</td>
			<td style="width:148px;"></td>
			<td style="width:119px;"></td>
			<td style="width:183px;">Bent paper clips work well</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Rimadyl (Carprofen)</td>
			<td style="width:148px;">Zoetis Inc</td>
			<td style="width:119px;"></td>
			<td>for veterinary use</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Saline solution</td>
			<td style="width:148px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Standard Forceps</td>
			<td style="width:148px;">Fine Science Tools</td>
			<td style="width:119px;">11006-12</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sterile Drape</td>
			<td style="width:148px;">Dynarex</td>
			<td style="width:119px;">4410</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">T-Pins</td>
			<td style="width:148px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

a rat carotid artery pressure-controlled segmental balloon injury with periadventitial therapeutic application

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the luminal surface area in arteries thereby reducing adequate blood flow to organs and distal tissues. Clinically, revascularization procedures such as balloon angioplasty with or without stent placement aim to restore blood flow. Although these procedures reestablish blood flow by reducing plaque burden, they damage the vessel wall, which initiates the arterial healing response. The prolonged healing response causes arterial restenosis, or re-narrowing, ultimately limiting the long-term success of these revascularization procedures. Therefore, preclinical animal models are integral for analyzing the pathophysiological mechanisms driving restenosis, and provide the opportunity to test novel therapeutic strategies. Murine models are cheaper and easier to operate on than large animal models. Balloon or wire injury are the two commonly accepted injury modalities used in murine models. Balloon injury models in particular mimic the clinical angioplasty procedure and cause adequate damage to the artery for the development of restenosis. Herein we describe the surgical details for performing and histologically analyzing the modified, pressure-controlled rat carotid artery balloon injury model. Additionally, this protocol highlights how local periadventitial application of therapeutics can be used to inhibit neointimal hyperplasia. Lastly, we present light sheet fluorescence microscopy as a novel approach for imaging and visualizing the arterial injury in three-dimensions.

Figure 1 shows all of the materials and surgical tools used to perform this surgery. Hematoxylin &#38; eosin (H&#38;E) staining of two-week injured arterial cross sections allows for clear visualization of neointimal hyperplasia. Figure 2 shows representative images of H&#38;E-stained arterial cross-sections of a healthy, injured, and treated artery. Figure 2 also outlines how to quantify the level of neointimal hyperplasia in an in...

Watch this Scientific Journal Video about A Rat Carotid Artery Pressure-Controlled Segmental Balloon Injury with Periadventitial Therapeutic Application at JoVE.com

A Rat Carotid Artery Pressure-Controlled Segmental Balloon Injury with Periadventitial Therapeutic Application

The rat carotid artery balloon injury mimics the clinical angioplasty procedure performed to restore blood flow in atherosclerotic vessels. This model induces the arterial injury response by distending the arterial wall, and denuding the intimal layer of endothelial cells, ultimately causing remodeling and an intimal hyperplastic response.

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the ...

The pressure-controlled segmental carotid balloon injury. Is an experimental procedure used in the lab that mimics the balloon angioplasty revascularization procedure that is performed in human patients with severe atherosclerotic disease. It's used in the lab to study various aspects of the arterial injury response.This re-stenosis model is performed in a similar manner to balloon angioplasty in the clinical setting allowing a defined area of vascular injury and complete re endothelialization within two weeks of injury to be achieved. After performing all of the preoperative procedures, according to the university IACUC standards, confirm a lack of response to pedal reflex in an anesthetized adult rat. Place the rat under a dissecting microscope and use scissors to make a straight 1.5 to two centimeter superficial longitudinal skin incision along the neck line between the jaw bones.Make a second incision through the connective tissue under the skin until the muscle layer is exposed. And displace the salivary glands underneath the skin to access the muscle tissue. Insert closed scissor tips between the muscle layer and connective tissue and gently opened the scissors while pulling the skin upward to bluntly separate the connective tissue from the muscle.Dissect the sternohyoid and sternomastoid muscles longitudinally along the left side of the trachea until the omohyoid muscle which runs perpendicular to the two superficial muscles is observed. Use forceps to gently create a window separating the perpendicular omohyoid muscle from the longitudinal sternohyoid muscle running over the trachea. And reach the forceps under the omohyoid muscle to separate the sternohyoid and sternomastoid muscles to expose the common carotid artery.To isolate the common carotid artery, dissect the artery near the bifurcation until the internal and external carotid arteries are exposed. Using precut Proline sutures, ligate the superior thyroid and external carotid arteries near their respective bifurcations. Leaving the majority of the suture to one side of the nod and grabbing each suture with a curved hemostat.Finish dissecting around the internal carotid artery and reach the forceps under and around the artery. Use a non crushing vascular clamp to carefully clamp around the occipital artery with the internal carotid artery to achieve distal control without kinking the vessels. Dissect the common carotid artery proximal to the bifurcation, taking care to separate the vagus nerve from the artery.And reach forceps under and around the common carotid artery. Then use a non crushing vascular clamp to achieve proximal control, placing the clamp at least five millimeters from the bifurcation. To induce the balloon injury, maneuver the curved hemostats holding each litigated artery branch to expose the bifurcation between the external carotid artery and superior branch.Gently dissect the tissue at the bifurcation to clear the arteriotomy site as much as possible. And use microdissection scissors to make an arteriotomy incision between the external carotid artery and the superior branch. Take care to clear the site prior to inserting the micro scissors and to ensure that one blade of the micro scissors is fully within the artery before making the incision.Use a cotton swab to push all of the blood out of the common carotid artery and to clean up the arteriotomy site. Insert the uninflated balloon catheter through the arteriotomy by lifting the arteriotomy with forceps. And advance the balloon into the artery until the proximal end of the balloon is past the bifurcation.If the balloon does not easily advance into the common carotid, reposition the angle of the balloon before trying again. Tape the catheter to the anesthesia nose cone so the balloon does not slip out of the artery during the inflation. And slowly fill the balloon to five atmospheres of pressure.Leave the balloon in the artery for five minutes to induce the arterial injury before deflating and gently removing the balloon through the arteriotomy. Gently squeeze the clamp to flush out the artery. And ligate the external carotid artery proximal to the arteriotomy.Remove the clamps from the common and internal carotid arteries to restore blood flow. And apply 50 microliters of therapeutic gel periadventiatially along the left and right sides of the injured artery. Then use interrupted 4-0 or 6-0 Vicryl sutures to close the connective tissue.And close the skin with a running 4-0 nylon suture. Here, representative images of H and E stained arterial cross-sections of healthy, injured and treated arteries are shown. Using image J the perimeter of the neointima as well as the internal and external elastic lamina can be traced to quantify their respective areas.Light sheet fluorescence microscopy can also be used to visualize the entire region of injury along the length of the artery. The images can then be rendered using software for quantifying the intima-media ratio. Be sure to place the internal carotid clamps so as not to kink the common carotid and to completely clear the arteriotomy site before inserting the microdissection scissors.Many therapeutic approaches can be used at the end of surgery to attempt to mitigate the pathological response that is occurring within the carotid artery.

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4.8K Views.  University of North Carolina at Chapel Hill. The pressure-controlled segmental carotid balloon injury. Is an experimental procedure used in the lab that mimics the balloon angioplasty revascularization procedure that is performed in human patients with severe atherosclerotic disease. It's used in the lab to study various aspects of the arterial injury response.This re-stenosis model is performed in a similar manner to balloon angioplasty in the clinical setting allowing a defined area of vascular injury and complete re endothelia...