Research was supported by NHLBI Research Scientist Development Grant (1K01HL135461-01) to JAG.&#160;Thank you to David Carmona-Berrio, and Isabel Adarve-Rengifo for their technical assistance.

Mice were housed and cared at the Vanderbilt University Medical Center (VUMC) Division of Animal Care following the National Institutes of Health (NIH) guidelines and the Guide for the Care and Use of Laboratory Animals, US Department of Health and Human Services. All animal procedures were approved by the VUMC Institutional Animal Care and Use Committee prior to starting the experiments.
1. Animal preparation and dissection
<ol>
	<li>Turn on the germinator and water pump of&#160;the heating...

<ol>
	<li>Kashyap, 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=Blockade+of+CCR2+reduces+macrophage+influx+and+development+of+chronic+renal+damage+in+murine+renovascular+hypertension.">Blockade of CCR2 reduces macrophage influx and development of chronic renal damage in murine renovascular hypertension.</a> American Journal of Physiology-Renal Physiology. 310 (5), 372-384 (2016).</li><li>Wang, W., 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=Changes+in+inflammatory+biomarkers+after+renal+revascularization+in+atherosclerotic+renal+artery+stenosis.">Changes in inflammatory biomarkers after renal revascularization in atherosclerotic renal artery stenosis.</a> Nephrology Dialysis Transplantation. 31 (9), 1437-1443 (2016).</li><li>Yerram, P., Karuparthi, P. R., Chaudhary, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogenesis+and+management+of+renovascular+hypertension+and+ischemic+nephropathy.">Pathogenesis and management of renovascular hypertension and ischemic nephropathy.</a> Minerva Urologica e Nefrologica. 64 (1), 63-72 (2012).</li><li>Covic, A., Gusbeth-Tatomir, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+the+renin-angiotensin-aldosterone+system+in+renal+artery+stenosis,+renovascular+hypertension,+and+ischemic+nephropathy:+diagnostic+implications.">The role of the renin-angiotensin-aldosterone system in renal artery stenosis, renovascular hypertension, and ischemic nephropathy: diagnostic implications.</a> Progress in Cardiovascular Diseases. 52 (3), 204-208 (2009).</li><li>Barreras, A., Gurk-Turner, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Angiotensin+II+receptor+blockers.">Angiotensin II receptor blockers.</a> Proceedings. 16 (1), 123-126 (2003).</li><li>Sica, 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=Angiotensin-converting+enzyme+inhibitors+side+effects--physiologic+and+non-physiologic+considerations.">Angiotensin-converting enzyme inhibitors side effects--physiologic and non-physiologic considerations.</a> Journal of Clinical Hypertension. 6 (7), 410-416 (2004).</li><li>Hill, R. D., Vaidya, P. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Angiotensin+II+Receptor+Blockers+(ARB,+ARb).">Angiotensin II Receptor Blockers (ARB, ARb).</a> StatPearls. , (2019).</li><li>Durante, A., 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=Role+of+the+renin-angiotensin-aldosterone+system+in+the+pathogenesis+of+atherosclerosis.">Role of the renin-angiotensin-aldosterone system in the pathogenesis of atherosclerosis.</a> Current Pharmaceutical Design. 18 (7), 981-1004 (2012).</li><li>Chen, 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=Plasma+reactive+carbonyl+species:+Potential+risk+factor+for+hypertension.">Plasma reactive carbonyl species: Potential risk factor for hypertension.</a> Free Radical Research. 45 (5), 568-574 (2011).</li><li>Zhang, X., 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=Angiotensin+receptor+blockade+has+protective+effects+on+the+poststenotic+porcine+kidney.">Angiotensin receptor blockade has protective effects on the poststenotic porcine kidney.</a> Kidney International. 84 (4), 767-775 (2013).</li><li>Zou, X., 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=Renal+scattered+tubular-like+cells+confer+protective+effects+in+the+stenotic+murine+kidney+mediated+by+release+of+extracellular+vesicles.">Renal scattered tubular-like cells confer protective effects in the stenotic murine kidney mediated by release of extracellular vesicles.</a> Scientific Reports. 8 (1), 1263 (2018).</li><li>Kinra, M., Mudgal, J., Arora, D., Nampoothiri, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+insight+into+the+role+of+cyclooxygenase+and+lipooxygenase+pathway+in+renal+ischemia.">An insight into the role of cyclooxygenase and lipooxygenase pathway in renal ischemia.</a> European Review for Medical and Pharmacological Sciences. 21 (21), 5017-5020 (2017).</li><li>Cavalcanti, C. O., 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+PDE5+Restores+Depressed+Baroreflex+Sensitivity+in+Renovascular+Hypertensive+Rats.">Inhibition of PDE5 Restores Depressed Baroreflex Sensitivity in Renovascular Hypertensive Rats.</a> Frontiers in Physiology. 7, 15 (2016).</li><li>Dias, A. 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=Sildenafil+ameliorates+oxidative+stress+and+DNA+damage+in+the+stenotic+kidneys+in+mice+with+renovascular+hypertension.">Sildenafil ameliorates oxidative stress and DNA damage in the stenotic kidneys in mice with renovascular hypertension.</a> Journal of Translational Medicine. 12, 35 (2014).</li><li>Lerman, L. O., Chade, A. R., Sica, V., Napoli, C. <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+hypertension:+an+overview.">Animal models of hypertension: an overview.</a> Journal of Laboratory and Clinical Medicine. 146 (3), 160-173 (2005).</li><li>Reckelhoff, J. F., Romero, D. G., Yanes Cardozo, L. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sex,+Oxidative+Stress,+and+Hypertension:+Insights+From+Animal+Models.">Sex, Oxidative Stress, and Hypertension: Insights From Animal Models.</a> Physiology (Bethesda). 34 (3), 178-188 (2019).</li><li>Goldblatt, H., Lynch, J., Hanzal, R. F., Summerville, W. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studies+on+Experimental+Hypertension+:+I.+The+Production+of+Persistent+Elevation+of+Systolic+Blood+Pressure+by+Means+of+Renal+Ischemia.">Studies on Experimental Hypertension : I. The Production of Persistent Elevation of Systolic Blood Pressure by Means of Renal Ischemia.</a> Journal of Experimental Medicine. 59 (3), 347-379 (1934).</li><li>Gollan, F., Richardson, E., Goldblatt, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypertension+in+the+systemic+blood+of+animals+with+experimental+renal+hypertension.">Hypertension in the systemic blood of animals with experimental renal hypertension.</a> Journal of Experimental Medicine. 88 (4), 389-400 (1948).</li><li>Lewis, H. A., Goldblatt, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studies+on+Experimental+Hypertension:+XVIII.+Experimental+Observations+on+the+Humoral+Mechanism+of+Hypertension.">Studies on Experimental Hypertension: XVIII. Experimental Observations on the Humoral Mechanism of Hypertension.</a> Bulletin of the New York Academy of Medicine. 18 (7), 459-487 (1942).</li><li>Warner, G. 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=Genetic+deficiency+of+Smad3+protects+the+kidneys+from+atrophy+and+interstitial+fibrosis+in+2K1C+hypertension.">Genetic deficiency of Smad3 protects the kidneys from atrophy and interstitial fibrosis in 2K1C hypertension.</a> American Journal of Physiology-Renal Physiology. 302 (11), 1455-1464 (2012).</li><li>Lorenz, J. 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=Renovascular+hypertension+using+a+modified+two-kidney,+one-clip+approach+in+mice+is+not+dependent+on+the+alpha1+or+alpha2+Na-K-ATPase+ouabain-binding+site.">Renovascular hypertension using a modified two-kidney, one-clip approach in mice is not dependent on the alpha1 or alpha2 Na-K-ATPase ouabain-binding site.</a> American Journal of Physiology-Renal Physiology. 301 (3), 615-621 (2011).</li><li>Ebina, K., Iwabuchi, T., Suzuki, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Histological+change+in+permanently+clipped+or+ligated+cerebral+arterial+wall.+Part+II:+Autopsy+cases+of+aneurysmal+neck+clipping.">Histological change in permanently clipped or ligated cerebral arterial wall. Part II: Autopsy cases of aneurysmal neck clipping.</a> Acta Neurochirurgica. 66 (1-2), 23-42 (1982).</li><li>Saleem, 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=Sox6:+A+new+modulator+of+renin+expression+during+physiological+conditions.">Sox6: A new modulator of renin expression during physiological conditions.</a> bioRxiv. , (2019).</li><li>Saleem, 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=Sox6+as+a+new+modulator+of+renin+expression+in+the+kidney.">Sox6 as a new modulator of renin expression in the kidney.</a> American Journal of Physiology-Renal Physiology. , (2019).</li><li>Chade, A. R., Williams, M. L., Engel, J., Guise, E., Harvey, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+translational+model+of+chronic+kidney+disease+in+swine.">A translational model of chronic kidney disease in swine.</a> American Journal of Physiology-Renal Physiology. 315 (2), 364-373 (2018).</li><li>Xue, Y., Xu, Z., Chen, H., Gan, W., Chong, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low-energy+shock+wave+preconditioning+reduces+renal+ischemic+reperfusion+injury+caused+by+renal+artery+occlusion.">Low-energy shock wave preconditioning reduces renal ischemic reperfusion injury caused by renal artery occlusion.</a> Acta Cir&#250;rgica Brasileira. 32 (7), 550-558 (2017).</li><li>Lalanne, A., Beaudeux, J. L., Bernard, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NGAL:+a+biomarker+of+acute+and+chronic+renal+dysfunction.">NGAL: a biomarker of acute and chronic renal dysfunction.</a> Annales de Biologie Clinique. 69 (6), 629-636 (2011).</li><li>Bolignano, D., 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=Neutrophil+gelatinase-associated+lipocalin+(NGAL)+as+a+marker+of+kidney+damage.">Neutrophil gelatinase-associated lipocalin (NGAL) as a marker of kidney damage.</a> American Journal of Kidney Diseases. 52 (3), 595-605 (2008).</li><li>Kashyap, 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=Development+of+renal+atrophy+in+murine+2+kidney+1+clip+hypertension+is+strain+independent.">Development of renal atrophy in murine 2 kidney 1 clip hypertension is strain independent.</a> Research in Veterinary Science. 107, 171-177 (2016).</li><li>Anderson, W. P., Woods, R. L., Kline, R. L., Korner, P. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+haemodynamic+responses+to+unilateral+renal+artery+stenosis+in+conscious+dogs.">Acute haemodynamic responses to unilateral renal artery stenosis in conscious dogs.</a> Clinical and Experimental Pharmacology and Physiology. 12 (3), 305-309 (1985).</li><li>Imanishi, 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=Critical+degree+of+renal+arterial+stenosis+that+causes+hypertension+in+dogs.">Critical degree of renal arterial stenosis that causes hypertension in dogs.</a> Angiology. 43 (10), 833-842 (1992).</li><li>Ziecina, R., Abramczyk, P., Lisiecka, A., Papierski, K., Przybylski, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adrenal-renal+portal+circulation+contributes+to+decrease+in+renal+blood+flow+after+renal+artery+stenosis+in+rats.">Adrenal-renal portal circulation contributes to decrease in renal blood flow after renal artery stenosis in rats.</a> Journal of Physiology and Pharmacology. 49 (4), 553-560 (1998).</li><li>Johnson, J. A., Ichikawa, S., Kurz, K. D., Fowler, W. L., Payne, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pressor+responses+to+vasopressin+in+rabbits+with+3-day+renal+artery+stenosis.">Pressor responses to vasopressin in rabbits with 3-day renal artery stenosis.</a> American Journal of Physiology. 240 (6), 862-867 (1981).</li><li>Eirin, A., 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=Changes+in+glomerular+filtration+rate+after+renal+revascularization+correlate+with+microvascular+hemodynamics+and+inflammation+in+Swine+renal+artery+stenosis.">Changes in glomerular filtration rate after renal revascularization correlate with microvascular hemodynamics and inflammation in Swine renal artery stenosis.</a> Circulation: Cardiovascular Interventions. 5 (5), 720-728 (2012).</li><li>Ma, Z., Jin, X., He, L., Wang, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CXCL16+regulates+renal+injury+and+fibrosis+in+experimental+renal+artery+stenosis.">CXCL16 regulates renal injury and fibrosis in experimental renal artery stenosis.</a> American Journal of Physiology-Heart and Circulatory. 311 (3), 815-821 (2016).</li><li>Cheng, 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=Temporal+analysis+of+signaling+pathways+activated+in+a+murine+model+of+two-kidney,+one-clip+hypertension.">Temporal analysis of signaling pathways activated in a murine model of two-kidney, one-clip hypertension.</a> American Journal of Physiology-Renal Physiology. 297 (4), 1055-1068 (2009).</li><li>Wiesel, P., Mazzolai, L., Nussberger, J., Pedrazzini, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-kidney,+one+clip+and+one-kidney,+one+clip+hypertension+in+mice.">Two-kidney, one clip and one-kidney, one clip hypertension in mice.</a> Hypertension. 29 (4), 1025-1030 (1997).</li><li>Johns, C., Gavras, I., Handy, D. 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Renal artery stenosis is an important cause of secondary or resistant hypertension, and kidney injury1,29. The two kidney one clip (2K1C) Goldblatt model has been employed to study RAStenosis induced renovascular hypertension1,17,18,19. A number of previous studies using various animals models have shown that stenosis in the renal arter...

Renal artery stenosis (RAStenosis) is an intractable problem affecting about 6% of people over 65 and in up to 40% of people with coronary or peripheral vascular disease1,2. Current treatments for the disease are limited; therefore, there is a critical need to develop new therapies to treat renovascular hypertension or resistant hypertension induced by RAStenosis. Renin angiotensin aldosterone system (RAAS) is the key pathway involved in the pathogenesis of RAStenosis induced hypertension or renovascular hypertension3,4. Known therapies targeting RAAS, such as ACE inhibitors or angiotensin receptor blockers, alleviate hypertension, but need close examining for kidney failure and hyperkalemia5,6,7. Renin catalyzes the rate-limiting step in RAAS; it converts angiotensinogen to angiotensin I. In atherosclerosis, plaque formation causes the narrowing of renal artery that drives renin secretion, resulting in renovascular hypertension and kidney damage8. A number of studies have reported increased levels of oxidative stress during renovascular hypertension in humans, which were corroborated with the two kidney one clip (2K1C) mice model as well as other hypertensive animal models2,9,10,11,12,13,14,15,16. The molecular mechanism of renin expression control during RAStenosis induced renovascular hypertension is not well understood and warrants further investigation.
Experimental animal models that reliably and reproducibly recapitulate RAStenosis are important in elucidating the cellular and molecular mechanisms of renin expression control for the development of novel therapies. The 2K1C mouse model is a well-established experimental model to study the pathogenesis of renovascular hypertension17,18,19,20. This model is generated by the constriction of the renal artery using a clip17,20,21, therefore producing renal artery occlusion that results in an increase in renin expression and hypertension17,19,20,21. However, there are no technical reports available, which describe a step by step procedure to generate renal artery stenosis in animal models.
Conventional U-shaped silver clips, polyurethane tubes and other clips have been used to constrict the renal artery to induce renal artery stenosis. Some studies have shown that the design and material of the&#160;clip are critical to obtaining reliable and reproducible data with the 2K1C animal model. According to Lorenz et al., the use of conventional U-designed silver clips induces a low success rate of hypertension (40-60%)21. Due to the clip design, the renal artery is press laterally, triggering a few constrictions and greater probability to be dislodged from the renal artery. Silver malleability and ductility may allow changes in clip widths; therefore, causing different hypertension levels among mice. Silver dioxides on the clip can cause perivascular inflammation, intimal proliferation, and tissue granulation, altering the renal artery diameter22. Due to the variability in the levels of hypertension obtained with the conventional U-design silver clip, Warner et al. and Lorenz et al. have successfully used a rounder-design polyurethane tubing to initiate renal artery stenosis in mice, generating a more reliable and consistent induction of the two kidney one clip animal model20,21.
In this report, we describe a surgical protocol to generate experimental RAStenosis in mice, using the polyurethane tubing to constrict the renal artery. The polyurethane round-design cuff is a more reproducible, reliable and low-cost clip to generate stenosis in mouse. The goal of this experimental model is to study and define the molecular and cellular mechanism of renin expression control during renal artery stenosis. We confirmed the success of RAStenosis mice model by measuring renin expression and kidney injury marker neutrophil gelatinase-associated lipocalin (N-GAL).

<table>
	<tbody>
		<tr>
			<td>Diet Gel</td>
			<td>Clear H2O</td>
			<td>Diet-Gel 76A</td>
			<td>Surgery recovery diet</td>
		</tr>
		<tr>
			<td>EMC Heated Hard pad</td>
			<td>Hallowell</td>
			<td>000A2788B</td>
			<td>Heating pads were used to keep mice warm</td>
		</tr>
		<tr>
			<td>Ethilon Nylon Suture</td>
			<td>Ethicon</td>
			<td>662G</td>
			<td>4-0 (1.5 metric), This suture was used to close the peritoneum, and skin</td>
		</tr>
		<tr>
			<td>Ethilon Nylon Suture</td>
			<td>Ethicon</td>
			<td>2815 G</td>
			<td>8-0 (0.4 metric), This suture was used to close cuff to tie and constrict the artery</td>
		</tr>
		<tr>
			<td>Germinator 500</td>
			<td>Braintree Scientific Inc.</td>
			<td>GER 5287</td>
			<td>Sterilize surgical tools between surgeries</td>
		</tr>
		<tr>
			<td>Ketoprofen</td>
			<td>Zoetis</td>
			<td>Ketofen</td>
			<td>Painkiller</td>
		</tr>
		<tr>
			<td>Polyurethane</td>
			<td>Braintree Scientific Inc.</td>
			<td>MRE-025</td>
			<td>This tube was used to initiate stenosis</td>
		</tr>
		<tr>
			<td>Povidone-iodine antiseptic swabsticks</td>
			<td>Medline</td>
			<td>MDS093901</td>
			<td>It was applied after hair removal and surgery on the skin</td>
		</tr>
		<tr>
			<td>Reflex 7 Clip Applier</td>
			<td>Roboz Surgical Instrument Co</td>
			<td>204-1000</td>
			<td>This clip applier was used to apply clip in case one or more sutures went off</td>
		</tr>
		<tr>
			<td>Sterile towel drapes</td>
			<td>Dynarex</td>
			<td>4410</td>
			<td>It was used as a bedsheet for mice during surgery</td>
		</tr>
		<tr>
			<td>Triple antibiotic ointment</td>
			<td>Medi-First</td>
			<td>22312</td>
			<td></td>
		</tr>
		<tr>
			<td>Water pump</td>
			<td>Stryker</td>
			<td>T/pump Professionals</td>
			<td>Used to warm and circulate water in the heating hard pad to keep mice warm during and post-surgery</td>
		</tr>
	</tbody>
</table>

a modified two kidney one clip mouse model of renin regulation in renal artery stenosis

Renal artery stenosis is a common condition in patients with coronary or peripheral vascular disease where the renin angiotensin aldosterone system (RAAS) is overactivated. In this context, there is a narrowing of the renal arteries that stimulate an increase in the expression and release of renin, the rate-limiting protease in RAAS. The resulting rise in renin expression is a known driver of renovascular hypertension, frequently associated with kidney injury and end organ damage. Thus, there is a great interest in developing novel treatments for this condition. The molecular and cellular mechanism of renin control in renal artery stenosis is not fully understood and warrants further investigation. To induce renal artery stenosis in mice, a modified 2 kidney 1 clip (2K1C) Goldblatt mouse model was developed. The right kidney was stenosed in wild type mice and sham operated mice were used as control. After renal artery stenosis, we determined renin expression and kidney injury. Kidneys were harvested, and fresh cortices were used to determine protein and mRNA expression of renin. This animal model is reproducible and can be used to study pathophysiological responses, molecular and cellular pathways involved in renovascular hypertension and kidney injury.

Renal artery constriction increases renin expression in the stenosed kidney while repressing expression in the contralateral kidney. The two kidney one clip (2K1C) or Goldblatt model of stenosis induces increased renin expression and kidney injury.&#160;This is recognized as the best representative model of unilateral renal artery stenosis in humans.
Expression of renin and prorenin (precursor of renin) were measured using immunoblotting. The data show that renin and prorenin expression increa...

Watch this Scientific Journal Video about A Modified Two Kidney One Clip Mouse Model of Renin Regulation in Renal Artery Stenosis at JoVE.com

A Modified Two Kidney One Clip Mouse Model of Renin Regulation in Renal Artery Stenosis

A modified 2 kidney 1 clip (2K1C) Goldblatt mouse model was developed using polyurethane tubing to initiate renal artery stenosis, inducing an increase in renin expression and kidney injury. Here, we describe a detailed procedure of preparing and placing the cuff onto the renal artery to generate a reproducible and consistent 2K1C mouse model.

Renal artery stenosis is a common condition in patients with coronary or peripheral vascular disease where the renin angiotensin aldosterone system (RAAS) ...

The 2K1C mouse model is a reliable and reproducible method to induce renal artery stenosis. This protocol is valuable in elucidating molecular mechanisms involved in renin expression control during renal vascular hypertension. This animal model mimics unilateral renal artery stenosis in humans.The reliability and reproducibility make it a good model to discern new therapeutic targets for treating renal vascular hypertension. This technique requires a basic knowledge of performing surgery in mice. There are two critical parts:tubing preparation, and placement of tubing in the renal artery.Both are described in detail. Constriction of the right renal artery using precisely-cut tubing is key. This video of the procedure will show learners how to cut the tubing, then access and constrict the artery.Begin by cutting the tubing for the stenosis procedure. Cut a 0.5-millimeter-length piece of polyurethane tubing with a sharp scalpel. Then make a cuff by removing 0.2-millimeters of the circumference with a lengthwise cut.Record the weight of the mice, which should be between 18 and 22 grams, to perform renal artery stenosis with the polyurethane tube. The weight of the mice is critical to perform the surgery. After anesthetizing and administering the painkiller to the mouse, place it back inside the cage until it is fully unconscious.Pinch the toe with forceps to check if the mouse is fully anesthetized and ready for the surgery. Lay the mouse on its back on a paper towel away from the surgery area and remove the hair of the lateral abdomen with an electric hair clipper following the opposite direction of hair growth. Clean the shaved area with a sterile alcohol gauze pad and apply topical povidone-iodine solution.Open the sterilized bag containing all the surgical equipment. Working under the dissecting microscope, use sterile sharp scissors to make a small flank incision about 0.5 centimeters away from the vertebrae. Proceed along the lumbar vertebrae and make a one-inch incision.Pull back the skin and muscle to expose the kidney. Then, clean and remove the surrounding fat with cotton swabs to isolate the renal artery. Isolate the renal nerve from the renal artery using the curved forceps.Clean the oozed fluid near the renal artery with a cotton swab. Place two nylon sutures under the right renal artery, make loose knots, and place the cuff around the main renal artery approximately equidistant between the kidney and aorta bifurcation. Close the cuff using the nylon sutures, making three knots for each suture to avoid the probability of losing the sutures after the surgery.Close the incision in the muscle by applying a simple continuous suture and make simple interrupted sutures to close the skin. Return the mice to their cage and leave the half cage on a circulating water heating pad for two to three hours for animals to recover from the surgery. Provide the animals with gel diet recovery food.On the next day, administer painkiller. Weigh the mice for the next two days and consult with the veterinarian if a mouse loses more than 20%of its weight. Inspect the mice daily to assess for redness, swelling, pain, or infection.Record the weight of each mouse. After euthanizing the animal, place it on a sterile platform in supine position. Secure and extend the limbs to limit movement and thoroughly spray the mouse with 70%ethanol.Use scissors to make a midline incision and open the abdomen and chest area. Pull back the skin and peritoneum wall, then carefully expose the heart and puncture the right ventricle. Remove both kidneys using forceps, keeping track of which kidney was stenosed.Remove the kidney capsules, clean them from any fat, and record the weight of each kidney separately. Cut a longitudinal section of both kidneys and fix them in 4%PFA overnight at four degrees Celsius for in situ hybridization and immunohistochemistry. Isolate the cortex of the remaining kidney and flash freeze it in liquid nitrogen to perform a Western blot.Store the samples at minus 80 degrees Celsius until further analysis. Renal artery constriction increases renin expression in the stenosed kidney, while repressing expression in the contralateral kidney. The two-kidney one-clip model of stenosis induced renin expression and increased kidney injury.Expression of renin and prorenin was measured using immunoblotting. The data show that renin and prorenin expression increased in the stenosed kidney compared to contralateral and sham kidneys, suggesting that the cuff was constricting the renal artery and causing changes in renal perfusion. Immunohistochemistry was performed to visualize the localization of renin expression.The images confirmed increased expression of renin in the clipped kidney. Moreover, juxtaglomerular cell recruitment along the afferent arterial was seen in the stenosed kidney. To investigate the effect on renin mRNA expression levels, in situ hybridization was performed.The data suggests increased renin mRNA and JG cell recruitment in the stenosed kidney. Another characteristic of renal artery stenosis is the upregulation of kidney injury markers due to changes in kidney perfusion, superoxide production, and hypertension. Therefore, N-GAL was measured with immunoblotting, showing that the acute kidney injury marker was highly upregulated in the stenosed kidney.When attempting this protocol, remember to place the nylon sutures around the renal artery before placing the cuff. It helps expedite the procedure.

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4.3K vues.  Vanderbilt University Medical Center. The 2K1C mouse model is a reliable and reproducible method to induce renal artery stenosis. This protocol is valuable in elucidating molecular mechanisms involved in renin expression control during renal vascular hypertension. This animal model mimics unilateral renal artery stenosis in humans.The reliability and reproducibility make it a good model to discern new therapeutic targets for treating renal vascular hypertension. This technique requires a basic knowledge of performing surge...