Name: a modified two kidney one clip mouse model of renin regulation in renal artery stenosis
Uploaded: 2020-10-26T13:00:00
Description: Watch this Scientific Journal Video about A Modified Two Kidney One Clip Mouse Model of Renin Regulation in Renal Artery Stenosis at JoVE.com

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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Research

JoVE Journal

Medicine

Use of a Hanging-weight System for Isolated Renal Artery Occlusion

In hospitalized patients, over 50% of cases of acute kidney injury (AKI) are caused by renal ischemia 1-3. A recent study of hospitalized patients revealed that only a mild increase in serum creatinine levels (0.3 to 0.4 mg/dl) is associated with a 70% greater risk of death than in persons without any increase 1. Along these lines, surgical procedures requiring cross-clamping of the aorta and renal vessels are associated with a renal failure rates of up to 30% 4. Similarly, AKI after cardiac surgery occurs in over 10% of patients under normal circumstances and is associated with dramatic increases in mortality. AKI are also common complications after liver transplantation. At least 8-17% of patients end up requiring renal replacement therapy 5. Moreover, delayed graft function due to tubule cell injury during kidney transplantation is frequently related to ischemia-associated AKI 6. Moreover, AKI occurs in approximately 20% of patients suffering from sepsis 6.The occurrence of AKI is associated with dramatic increases of morbidity and mortality 1. Therapeutic approaches are very limited and the majority of interventional trials in AKI have failed in humans. Therefore, additional therapeutic modalities to prevent renal injury from ischemia are urgently needed 3, 7-9. 
To elucidate mechanisms of renal injury due to ischemia and possible therapeutic strategies murine models are intensively required 7-13. Mouse models provide the possibility of utilizing different genetic models including gene-targeted mice and tissue specific gene-targeted mice (cre-flox system). However, murine renal ischemia is technically challenging and experimental details significantly influence results. We performed a systematic evaluation of a novel model for isolated renal artery occlusion in mice, which specifically avoids the use of clamping or suturing the renal pedicle 14. This model requires a nephrectomy of the right kidney since ischemia can be only performed in one kidney due to the experimental setting. In fact, by using a hanging-weight system, the renal artery is only instrumented once throughout the surgical procedure. In addition, no venous or urethral obstruction occurs with this technique. We could demonstrate time-dose-dependent and highly reproducible renal injury with ischemia by measuring serum creatinine. Moreover, when comparing this new model with conventional clamping of the whole pedicle, renal protection by ischemic preconditioning is more profound and more reliable. Therefore his new technique might be useful for other researchers who are working in the field of acute kidney injury.

A precise murine model for acute kidney injury (AKI) due to ischemia is an important tool to investigate acute kidney injury and possibly find therapeutic tools to treat renal injury. The hanging weight system offers a tool for immediate and reliable renal artery occlusion and reperfusion without causing renal congestion.

In hospitalized patients, over 50% of cases of acute kidney injury (AKI) are caused by renal ischemia 1-3. A recent study of hospitalized patients ...

Mouse Model of Middle Cerebral Artery Occlusion

Stroke is the most common fatal neurological disease in the United States 1. The majority of strokes (88%) result from blockage of blood vessels in the brain (ischemic stroke) 2. Since most ischemic strokes (~80%) occur in the territory of middle cerebral artery (MCA) 3, many animal stroke models that have been developed have focused on this artery. The intraluminal monofilament model of middle cerebral artery occlusion (MCAO) involves the insertion of a surgical filament into the external carotid artery and threading it forward into the internal carotid artery (ICA) until the tip occludes the origin of the MCA, resulting in a cessation of blood flow and subsequent brain infarction in the MCA territory 4. The technique can be used to model permanent or transient occlusion 5. If the suture is removed after a certain interval (30 min, 1 h, or 2 h), reperfusion is achieved (transient MCAO); if the filament is left in place (24 h) the procedure is suitable as a model of permanent MCAO. This technique does not require craniectomy, a neurosurgical procedure to remove a portion of skull, which may affect intracranial pressure and temperature 6. It has become the most frequently used method to mimic permanent and transient focal cerebral ischemia in rats and mice 7,8. To evaluate the extent of cerebral infarction, we stain brain slices with 2,3,5-triphenyltetrazolium chloride (TTC) to identify ischemic brain tissue 9. In this video, we demonstrate the MCAO method and the determination of infarct size by TTC staining.

We demonstrate in the video a method for producing a middle cerebral artery occlusion in adult mice using an intraluminal monofilament. We also show how to evaluate the extent of cerebral infarction by 2,3,5-triphenyltetrazolium chloride (TTC) staining.

Stroke is the most common fatal neurological disease in the United States 1. The majority of strokes (88%) result from blockage of blood vessels in the ...

Assessment of Vascular Function in Patients With Chronic Kidney Disease

Patients with chronic kidney disease (CKD) have significantly increased risk of cardiovascular disease (CVD) compared to the general population, and this is only partially explained by traditional CVD risk factors. Vascular dysfunction is an important non-traditional risk factor, characterized by vascular endothelial dysfunction (most commonly assessed as impaired endothelium-dependent dilation [EDD]) and stiffening of the large elastic arteries. While various techniques exist to assess EDD and large elastic artery stiffness, the most commonly used are brachial artery flow-mediated dilation (FMDBA) and aortic pulse-wave velocity (aPWV), respectively. Both of these noninvasive measures of vascular dysfunction are independent predictors of future cardiovascular events in patients with and without kidney disease. Patients with CKD demonstrate both impaired FMDBA, and increased aPWV. While the exact mechanisms by which vascular dysfunction develops in CKD are incompletely understood, increased oxidative stress and a subsequent reduction in nitric oxide (NO) bioavailability are important contributors. Cellular changes in oxidative stress can be assessed by collecting vascular endothelial cells from the antecubital vein and measuring protein expression of markers of oxidative stress using immunofluorescence. We provide here a discussion of these methods to measure FMDBA, aPWV, and vascular endothelial cell protein expression.

The degree of vascular dysfunction and contributing physiological mechanisms can be assessed in patients with chronic kidney disease by measuring brachial artery flow-mediated dilation, aortic pulse-wave velocity, and vascular endothelial cell protein expression.

Patients with chronic kidney disease (CKD) have significantly increased risk of cardiovascular disease (CVD) compared to the general population, and this ...

Renal Ischaemia Reperfusion Injury: A Mouse Model of Injury and Regeneration

Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable during renal transplantation. Experimental models that accurately and reproducibly recapitulate renal IRI are crucial in dissecting the pathophysiology of AKI and the development of novel therapeutic agents. Presented here is a mouse model of renal IRI that results in reproducible AKI. This is achieved by a midline laparotomy approach for the surgery with one incision allowing both a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia of the left kidney. By careful monitoring of the clamp position and body temperature during the period of ischaemia this model achieves reproducible functional and structural injury. Mice sacrificed 24 hr&#160;following surgery demonstrate loss of renal function with elevation of the serum or plasma creatinine level as well as structural kidney damage with acute tubular necrosis evident. Renal function improves and the acute tissue injury resolves during the course of 7 days following renal IRI such that this model may be used to study renal regeneration. This model of renal IRI has been utilized to study the molecular and cellular pathophysiology of AKI as well as analysis of the subsequent renal regeneration.

The mouse model of renal ischaemia reperfusion injury described here comprises of a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia that results in acute kidney injury. This model uses a midline laparotomy approach with all steps performed via one incision.

Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable ...

Murine Kidney Transplant Technique

The first mouse kidney transplant technique was published in 19731 by the Russell laboratory. Although it took some years for other labs to become proficient in and utilize this technique, it is now widely used by many laboratories around the world. A significant refinement to the original technique using the donor aorta to form the arterial anastomosis instead of the renal artery was developed and reported in 1993 by Kalina and Mottram 2 with a further advancement coming from the same laboratory in 1999 3. While one can become proficient in this model, a search of the literature reveals that many labs still experience a high proportion of graft loss due to arterial thrombosis. We describe here a technique that was devised in our laboratory that vastly reduces the arterial thrombus reported by others 4,5. This is achieved by forming a heel-and-toe cuff of the donor infra-renal aorta that facilitates a larger anastomosis and straighter blood flow into the kidney.

The goal of this manuscript is to describe the steps required to perform a kidney transplant in a mouse, paying particular attention to the details of the arterial anastomosis.

The first mouse kidney transplant technique was published in 19731 by the Russell laboratory. Although it took some years for other labs to become ...

Mouse Model for Pancreas Transplantation Using a Modified Cuff Technique

Mouse models have several advantages in transplantation research, including easy handling, a variety of genetically well-defined strains, and the availability of the widest range of molecular probes and reagents to perform in vivo as well as in vitro studies. Based on our experience with various murine transplantation models, we developed a heterotopic pancreas transplantation model in mice with the intent to analyze mechanisms underlying severe ischemia reperfusion injury-associated early graft damage. In contrast to previously described techniques using suture techniques, herein we describe a new procedure using a non-suture cuff technique. 
In recent years, we have performed more than 300 pancreas transplantations in mice with an overall success rate of &gt;90%, a success rate never described before in mouse pancreas transplantation. The backbone of this non-suture cuff technique for graft revascularization consists of two major steps: (I) pulling the recipient vessel over a polyethylene/polyamide cuff and fixing it with a circumferential ligature, and (II) placing the donor vessel over the everted recipient vessel and fixing it with a second circumferential ligature. The resultant continuity of the endothelial layer results in less thrombogenic lesions with high patency rates and, finally, high success rates.
In this model, arterial anastomosis is achieved by pulling the abdominal aorta of the donor graft over the everted common carotid artery of the recipient animal. Venous drainage of the graft is achieved by pulling the portal vein of the graft over the everted external jugular vein of the recipient. This manuscript provides details and crucial steps of the organ recovery and organ implantation procedures, which will allow researchers with microsurgical skills to perform the transplantation successfully in their laboratories.

Among abdominal solid organ transplantation, pancreatic grafts are prone to develop severe ischemia reperfusion injury-associated graft damage, leading eventually to early graft loss. This protocol describes a model of murine pancreas transplantation using a non-suture cuff technique, ideally suited for analyzing these early, deleterious damages.

Mouse models have several advantages in transplantation research, including easy handling, a variety of genetically well-defined strains, and the ...

Assessment of Kidney Function in Mouse Models of Glomerular Disease

The use of murine models to mimic human kidney disease is becoming increasingly common. Our research is focused on the assessment of glomerular function in diabetic nephropathy and podocyte-specific VEGF-A knock-out mice; therefore, this protocol describes the full kidney work-up used in our lab to assess these mouse models of glomerular disease, enabling a vast amount of information regarding kidney and glomerular function to be obtained from a single mouse. In comparison to alternative methods presented in the literature to assess glomerular function, the use of the method outlined in this paper enables the glomerular phenotype to be fully evaluated from multiple aspects. By using this method, the researcher can determine the kidney phenotype of the model and assess the mechanism as to why the phenotype develops. This vital information on the mechanism of disease is required when examining potential therapeutic avenues in these models. The methods allow for detailed functional assessment of the glomerular filtration barrier through measurement of the urinary albumin creatinine ratio and individual glomerular water permeability, as well as both structural and ultra-structural examination using the Periodic Acid Schiff stain and electron microscopy. Furthermore, analysis of the genes dysregulated at the mRNA and protein level enables mechanistic analysis of glomerular function. This protocol outlines the generic but adaptable methods that can be applied to all mouse models of glomerular disease.

This protocol describes a full kidney work-up that should be carried out in mouse models of glomerular disease. The methods allow for detailed functional, structural, and mechanistic analysis of glomerular function, which can be applied to all mouse models of glomerular disease.

The use of murine models to mimic human kidney disease is becoming increasingly common. Our research is focused on the assessment of glomerular function ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

An Efficient Sieving Method to Isolate Intact Glomeruli from Adult Rat Kidney

Preservation of glomerular structure and function is pivotal in the prevention of glomerulonephritis, a category of kidney disease characterized by proteinuria which can eventually lead to chronic and end-stage renal disease. The glomerulus is a complex apparatus responsible for the filtration of plasma from the body. In disease, structural integrity is lost and allows for the abnormal leakage of plasma contents into the urine. A method to isolate and examine glomeruli in culture is critical for the study of these diseases. In this protocol, an efficient method of retrieving intact glomeruli from adult rat kidneys while conserving structural and morphological characteristics is described. This process is capable of generating high yields of glomeruli per kidney with minimal contamination from other nephron segments. With these glomeruli, injury conditions can be mimicked by incubating them with a variety of chemical toxins, including protamine sulfate, which causes foot process effacement and proteinuria in animal models. Degree of injury can be assessed using transmission electron microscopy, immunofluorescence staining, and western blotting. Nephrin and Wilms Tumor 1 (WT1) levels can also be assessed from these cultures. Due to the ease and flexibility of this protocol, the isolated glomeruli can be utilized as described or in a way that best suits the needs of the researcher to help better study glomerular health and structure in diseased states.

The main focus of this protocol is to efficiently isolate viable primary glomeruli cultures with minimal contaminants for use in a variety of downstream applications. The isolated glomeruli retain structural relationships between component cell types and can be cultured ex vivo for a short time.

Preservation of glomerular structure and function is pivotal in the prevention of glomerulonephritis, a category of kidney disease characterized by ...

Direct Drug Delivery to Kidney via the Renal Artery

There is a need for directed injections to enable increased and specific renal exposure for efficient evaluation of drug targets in the renal research field. Accumulation of drugs in certain organs may give rise to adverse and unwanted effects, depending on the nature of injectate. To minimize spillover and/or accumulation in other tissues, the herein described method directs the formulation into the renal artery bloodstream by inserting a catheter in the infra renal aorta, just below where it branches into the renal artery, resulting in the kidney as first reached organ and distributing of formulation throughout the kidney.
This manuscript provides a detailed description of the method, as well as its challenges and difficulties. It guides the experimenter to become skillful with this type of microsurgery that requires accuracy under sterile conditions. Speed is crucial for minimizing the ischemia and practicing the procedure will increase the chance of successful injections without adverse effects. By modulating the time between injection and reperfusion as well as the injected volume, the risk of spillover to other organs is mitigated. 
Note that this technique is suitable for single dosing strategies.

This manuscript describes a method for targeted delivery to a single kidney via a catheter placed in the infrarenal abdominal aorta in the mouse.

There is a need for directed injections to enable increased and specific renal exposure for efficient evaluation of drug targets in the renal research ...