Gli esperimenti sono stati condotti su ratti femmina Sprague-Dawley, del peso di 250-300 g. Tutte le procedure sugli animali rispettate le norme indicate nella Guida per la cura e l&#39;uso di animali da laboratorio (Istituto di laboratorio risorse animali, National Academy of Sciences, Bethesda, MD, USA) e sono stati approvati dal Mayo Clinic College of Medicine Istituzionale Animal Care e Comitato Usa (IACUC). 1. Preparazione <ol><li> Autoclavare tutti gli strumenti chirurgici prima dell&#39;intervento chirurgico. Se interventi chirurgici multipli su diversi ratti sono in programma nella stessa giornata, lavare gli strumenti dopo ogni procedura di animale e poi sterilizzare utilizzando uno sterilizzatore a caldo tallone. </li><li> Anestetizzare il topo con il 4% isoflurano in 1 L / min O 2. </li><li> Trasferire il ratto ad una piastra elettrica controllata per mantenere la temperatura corporea a 37 ° C. Mantenere l&#39;anestesia con il 1-2% isoflurano in 1 L / min O 2. </li><li> Somministrare il farmaco analgesico (buprenorfina sostenuta di uscita 0,6 mg / kg) subcutaneously. </li><li> Applicare una pomata per gli occhi per evitare l&#39;essiccazione durante la procedura. </li><li> Al fine di compensare la perdita di fluidi corporei causa laparotomia, è importante somministrare 10 ml / kg di 0,9% sottocutanea soluzione fisiologica prima dell&#39;intervento. </li><li> Radere la zona addominale e pulire la pelle con i rilievi etanolo povidone-iodio e il 70%. </li></ol> 2. Procedura chirurgica <ol><li> Assicurarsi che la profondità di sedazione è adeguato per il monitoraggio riflessi fisici, quali il recesso dal pizzico punta, riflesso palpebrale, il tono della mascella, e la respirazione tasso / modello. </li><li> Eseguire una laparotomia attraverso una piccola incisione mediana (2-2,5 cm di lunghezza) con un bisturi chirurgico lama No. 10. </li><li> Estrarre l&#39;intestino e colon al lato destro dell&#39;addome utilizzando tamponi di cotone e coprire con garza sterile imbevuta di 0,9% soluzione salina per mantenere gli organi umido. </li><li> Delicatamente rientrare verso l&#39;alto la milza, fegato, stomaco e del pancreas per esporre la aorta e l&#39;arteria renale sinistra. </li><li> Con l&#39;aiuto di un microscopio operatorio, separare con attenzione l&#39;aorta addominale sopra e sotto il rene sinistro e l&#39;arteria renale sinistra dalle vene, il grasso e il tessuto connettivo circostante con dissezione curvo forcipe smussato e tamponi di cotone sterili. <ol><li> Utilizzare le pinze con un moto (scollamento) open-close ripetuto lungo la lunghezza delle navi per rimuovere il tessuto connettivo e le tamponi di cotone con un moto di rollio laterale per rimuovere il grasso. NOTA: La dissezione della regione peri-aortica è un passo molto delicato come nervi e vasi linfatici potrebbe essere danneggiata. Assicurarsi di mantenere le arterie umido con soluzione salina durante la procedura di dissezione. </li></ol></li><li> Collocare una sutura 4-0 seta sotto l&#39;aorta. </li><li> Utilizzando clip microvascolari, bloccare l&#39;aorta sopra (appena sotto l&#39;arteria mesenterica superiore) e al di sotto della biforcazione dell&#39;arteria renale. </li><li> Puntura dell&#39;aorta a livello della kidn sinistrabiforcazione dell&#39;arteria ey con un catetere endovenoso G 24 e far avanzare il catetere nell&#39;arteria renale. NOTA: questo è un passo fondamentale, come la puntura attraverso l&#39;arteria renale può verificarsi. </li><li> Collegare una siringa riempita con la soluzione farmaco o salina (fino a 500 microlitri) al catetere e profumato rene. </li><li> Subito dopo perfusione, bloccare la vena renale sinistra e dell&#39;uretere sinistro con una clip microvascolare e rimuovere il catetere. Poi, posizionare un pezzo di spugna assorbibile emostatico gelatina, con una piccola goccia di tessuto adesivo, sopra la zona forata dell&#39;aorta e applicare delicatamente pressione con un tampone di cotone. </li><li> Allo stesso tempo, rilasciare il morsetto dall&#39;aorta addominale, sotto fianco biforcazione dell&#39;arteria renale. Dopo 5 minuti, rilasciare il morsetto dalla vena renale e dell&#39;uretere. </li><li> rilasciare con cautela il morsetto dall&#39;aorta, sopra a sinistra biforcazione dell&#39;arteria renale, e consentire la riperfusione renale. L&#39;ischemia renale totale dovrebbe durare non più di 7 minuti. </li><li&gt; garantire che non si verifichino sanguinamento attivo e osservare da vicino l&#39;area per altri 10 min. </li><li> Chiudere l&#39;incisione addominale in due strati (muscoli e la pelle), con 4-0 punti di sutura assorbibili e un modello continuo per prevenire l&#39;infezione. Oltre alla tecnica modello sutura continua, un&#39;altra opzione potrebbe essere quella di utilizzare una tecnica semplice ed interrotta, particolarmente per la chiusura parete del corpo per evitare deiscenza. </li><li> Applicare topico pomata antibiotica sopra l&#39;area di incisione per prevenire le infezioni. </li><li> Trasferire il ratto in una gabbia di osservazione libera assestamento su un rilievo caldo fino al recupero completo con una gamma di temperatura impostata a 35-37 ° C. Assestamento allentato dovrebbe essere coperto (ad esempio con un asciugamano drappo o carta) o rimosso dalla gabbia fino a quando gli animali sono completamente recuperati per impedire il soffocamento o aspirazione di biancheria da letto. </li><li> Dopo l&#39;intervento chirurgico, osservare gli animali continuamente fino a quando la respirazione spontanea, poi ogni ora per un paio d&#39;ore. Re-dosare l&#39;analgesico buprenorfina SR 72 orein seguito, se si osservano segni di disagio, come la letargia, curvo e trasandato, smorfia, non riprendere le normali attività. </li><li> Dopo il completamento di tutti gli studi, eutanasia degli animali con l&#39;inalazione di una dose eccessiva di CO 2 e di raccogliere i tessuti renali di analisi ex vivo come istologia e Western Blotting 5. </li></ol>

<ol>
	<li>Dejani, H., Eisen, T. D., Finkelstein, F. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Revascularization+of+renal+artery+stenosis+in+patients+with+renal+insufficiency.">Revascularization of renal artery stenosis in patients with renal insufficiency.</a> Am. J. Kidney Dis. 36 (4), 752-758 (2000).</li><li>Kang, D. H., 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=Impaired+angiogenesis+in+the+remnant+kidney+model:+I.+Potential+role+of+vascular+endothelial+growth+factor+and+thrombospondin-1.">Impaired angiogenesis in the remnant kidney model: I. Potential role of vascular endothelial growth factor and thrombospondin-1.</a> J. Am. Soc. Nephrol. 12 (7), 1434-1447 (2001).</li><li>Kang, D. H., Hughes, J., Mazzali, M., Schreiner, G. F., Johnson, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impaired+angiogenesis+in+the+remnant+kidney+model:+II.+Vascular+endothelial+growth+factor+administration+reduces+renal+fibrosis+and+stabilizes+renal+function.">Impaired angiogenesis in the remnant kidney model: II. Vascular endothelial growth factor administration reduces renal fibrosis and stabilizes renal function.</a> J. Am. Soc. Nephrol. 12 (7), 1448-1457 (2001).</li><li>Kang, D. H., 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+microvascular+endothelium+in+progressive+renal+disease.">Role of the microvascular endothelium in progressive renal disease.</a> J. Am. Soc. Nephrol. 13 (3), 806-816 (2002).</li><li>Chade, A. R., Kelsen, S. <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+renal+dysfunction+by+targeted+administration+of+VEGF+into+the+stenotic+kidney:+a+novel+potential+therapeutic+approach.">Reversal of renal dysfunction by targeted administration of VEGF into the stenotic kidney: a novel potential therapeutic approach.</a> Am. J. Physiol.- Renal Physiol. 302 (10), F1342-F1350 (2012).</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> Circ.-Cardiovasc. Interv. 5 (5), 720-728 (2012).</li><li>Chade, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinct+Renal+Injury+in+Early+Atherosclerosis+and+Renovascular+Disease.">Distinct Renal Injury in Early Atherosclerosis and Renovascular Disease.</a> Circulation. 106 (9), 1165-1171 (2002).</li><li>Seddon, M., Saw, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atherosclerotic+renal+artery+stenosis:+review+of+pathophysiology,+clinical+trial+evidence,+and+management+strategies.">Atherosclerotic renal artery stenosis: review of pathophysiology, clinical trial evidence, and management strategies.</a> Can. J. Cardiol. 27 (4), 468-480 (2011).</li><li>Lao, D., Parasher, P. S., Cho, K. C., Yeghiazarians, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atherosclerotic+renal+artery+stenosis--diagnosis+and+treatment.">Atherosclerotic renal artery stenosis--diagnosis and treatment.</a> Mayo Clin Proc. 86 (7), 649-657 (2011).</li><li>Sharfuddin, A. A., Molitoris, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathophysiology+of+ischemic+acute+kidney+injury.">Pathophysiology of ischemic acute kidney injury.</a> Nat. Rev. Nephrol. 7, 189-200 (2011).</li><li>Noiri, 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=Oxidative+and+nitrosative+stress+in+acute+renal+ischemia.">Oxidative and nitrosative stress in acute renal ischemia.</a> Am. J. Physiol.- Renal Physiol. 281 (5), F948-F957 (2001).</li><li>Koesters, 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=Tubular+Overexpression+of+Transforming+Growth+Factor-&#206;1+Induces+Autophagy+and+Fibrosis+but+Not+Mesenchymal+Transition+of+Renal+Epithelial+Cells.">Tubular Overexpression of Transforming Growth Factor-&#206;1 Induces Autophagy and Fibrosis but Not Mesenchymal Transition of Renal Epithelial Cells.</a> Am. J. Pathol. 177 (2), 632-643 (2010).</li><li>Shanley, P. F., Rosen, M. D., Brezis, M., Silva, P., Epstein, F. H., Rosen, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Topography+of+focal+proximal+tubular+necrosis+after+ischemia+with+reflow+in+the+rat+kidney.">Topography of focal proximal tubular necrosis after ischemia with reflow in the rat kidney.</a> Am. J. Pathol. 122 (3), 462-468 (1986).</li></ol>

Questo lavoro è in parte sostenuto da un assegno di ricerca da Astra Zeneca.

The increasing incidence of chronic kidney disease raises the need for novel therapeutic approaches that can promote functional kidney recovery7,8. Traditional therapies include the systemic administration of anti-inflammatory, anti-fibrotic drugs9. However, these strategies are frequently characterized by unwanted side effects due to off-target distribution of the injected drug. Therefore, in this manuscript, we describe a simple procedure for delivering drugs into the renal artery of rats. This pr...

The renal microvasculature is involved in a wide spectrum of kidney diseases. Depending on the pathophysiology of disease, the endothelial cells may present structural or functional impairment, which may play a pivotal role in propagating kidney damage by creating an ischemic microenvironment. This renal microvascular dysfunction may catalyze the onset of a progressive deterioration of renal function over time, leading to chronic kidney disease (CKD), end-stage renal disease, hypertension and cardiorenal syndrome. In fact, untreated hypertension may have implications in renal arterioles, causing nephrosclerosis or glomerulosclerosis with significant reduction in vascular volume fraction, increase in vascular resistance and development of tubulointerstitial fibrosis1.
Loss of renal microvasculature may be due to altered vascular homeostasis induced by local angiogenic/anti-angiogenic factors imbalance. This correlates with attenuated Vascular Endothelial Growth Factor (VEGF) signaling as well as elevated thrombospondin-12-4. Thus, using different animal models (mice, rats and pigs), the therapeutic effect of exogenous administration of VEGF has been recently investigated in some forms of renal disease, showing reduced interstitial fibrosis and stabilized renal and cardiac function3-5. This effect is likely due to actions of VEGF on endothelial cells of the microvascular bed and inflammatory monocyte phenotype switching6.
For some preclinical studies, the use of rodents, the most commonly used laboratory animals, provides a good animal model for high throughput studies due to relatively low costs and ease of handling. Moreover, the use of genetically-altered rats as models of human diseases, such as hypertension, has become more and more frequent in the scientific community. Therefore, the aim of this protocol is to describe a useful intrarenal VEGF delivery technique in rats that is easy to perform and highly reproducible. Moreover, the same method can be used to selectively deliver other drugs.

<table border="0" cellpadding="0" cellspacing="0" width="928">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Surgical Microscope</td>
			<td style="width:176px;">Leica</td>
			<td style="width:119px;">M125</td>
			<td style="width:376px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Isoflurane 100 ml</td>
			<td style="width:176px;">Cardinal Healthcare</td>
			<td style="width:119px;">PI23238</td>
			<td>Anesthetic</td>
		</tr>
		<tr height="133">
			<td height="133" style="height:133px;width:257px;">Buprenorphine HCL SR LAB 1mg/ml, 5 ml</td>
			<td style="width:176px;">ZooPharm Pharmacy</td>
			<td style="width:119px;"></td>
			<td style="width:376px;">Buprenorphine narcotic analgesic formulated in a polymer that slows absorption extending duration of action (72 hours duration of activity).&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Liquid is viscous, warming to room temperature aids in drawing into syringe.&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Recommended dosage: 1-1.2 mg/kg SC. DO NOT DILUTE.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">Puralube Vet Ophthalmic Ointment</td>
			<td style="width:176px;">Dechra</td>
			<td style="width:119px;">NDC17033-211-38</td>
			<td>Sterile ocular lubricant</td>
		</tr>
		<tr height="56">
			<td height="56" style="height:56px;width:257px;">Lactated Ringer&#39;s Injection, USP, 250 mL VIAFLEX Plastic Container</td>
			<td style="width:176px;">Baxter Healthcare Corp.</td>
			<td style="width:119px;">NDC0338-0117-02</td>
			<td>For body fluids replacement</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Sol Povidone-Iodine&#160; Swabstick, 3&#39;&#160;</td>
			<td style="width:176px;">Cardinal Heatlhcare</td>
			<td style="width:119px;">23405-010B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Sterile cotton tipped applicators</td>
			<td style="width:176px;">Kendall</td>
			<td style="width:119px;">8884541300</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">4-0 silk suture (without needle)&#160;</td>
			<td style="width:176px;">Cardinal Heatlhcare</td>
			<td style="width:119px;">A183H</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">Vessel Clip, Straight, 0.75 x 4mm Jaw</td>
			<td style="width:176px;">World Precision Instruments&#160;</td>
			<td style="width:119px;">501779-G</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">I.V. Catheter, Straight Hub, Radiopaque, 24g x 3/4&#34;, FEP Polymer</td>
			<td style="width:176px;">Jelco</td>
			<td align="right" style="width:119px;">4053</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Phosphate Buffered Saline</td>
			<td style="width:176px;">Life Technologies</td>
			<td align="right" style="width:119px;">10010023</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">SURGIFOAM Absorbable Gelatin Sponge</td>
			<td style="width:176px;">Cardinal Healthcare</td>
			<td align="right" style="width:119px;">179082</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">4-0 VICRYL PLUS (ANTIBACTERIAL) VIOLET 27&#34; RB-1 TAPER</td>
			<td style="width:176px;">Ethicon</td>
			<td style="width:119px;">VCP304H</td>
			<td>For muscle layer suturing</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">4-0 VICRYL PLUS (ANTIBACTERIAL) UNDYED 18&#34; PC-3 CUTTING</td>
			<td style="width:176px;">Ethicon</td>
			<td style="width:119px;">VCP845G</td>
			<td>For skin layer suturing</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">Triple antibiotic ointment</td>
			<td style="width:176px;">Actavis</td>
			<td style="width:119px;">NDC0472-0179-56</td>
			<td>For topical use on the site of the incision</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Recombinant Rat VEGF 164 Protein</td>
			<td style="width:176px;">R&#38;D Sytems</td>
			<td style="width:119px;">564-RV</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Rabbit monoclonal VEGFA</td>
			<td style="width:176px;">Abcam</td>
			<td style="width:119px;">ab46154</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Rabbit monoclonal FLK1</td>
			<td style="width:176px;">Cell Signaling</td>
			<td align="right" style="width:119px;">9698</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:257px;">Rabbit monoclonal AKT</td>
			<td style="width:176px;">Cell Signaling</td>
			<td align="right" style="width:119px;">4691</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">Rabbit monoclonal phosphoAKT (Ser 473)</td>
			<td style="width:176px;">Cell Signaling</td>
			<td align="right" style="width:119px;">4060</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">Rabbit monoclonal p44/42 MAPK (ERK1/2)</td>
			<td style="width:176px;">Cell Signaling</td>
			<td align="right" style="width:119px;">4695</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:257px;">Rabbit monoclonal phospho p44/42 MAPK (Thr202 and Tyr 204)</td>
			<td style="width:176px;">Cell Signaling</td>
			<td align="right" style="width:119px;">4370</td>
			<td></td>
		</tr>
	</tbody>
</table>

intravascular delivery of biologics to the rat kidney

The renal microvascular compartment plays an important role in the progression of kidney disease and hypertension, leading to the development of End Stage Renal Disease with high risk of death for cardiovascular events. Moreover, recent clinical studies have shown that renovascular structure and function may have a great impact on functional renal recovery after surgery. Here, we describe a protocol for the delivery of drugs into the renal artery of rats. This procedure offers significant advantages over the frequently used systemic administration as it may allow a more localized therapeutic effect. In addition, the use of rodents in pharmacodynamic analysis of preclinical studies may be cost effective, paving the way for the design of translational experiments in larger animal models. Using this technique, infusion of rat recombinant Vascular Endothelial Growth Factor (VEGF) protein in rats has induced activation of VEGF signaling as shown by increased expression of FLK1, pAKT/AKT, pERK/ERK. In summary, we established a protocol for the intrarenal delivery of drugs in rats, which is simple and highly reproducible.

<html> Abbiamo iniettato due diverse dosi di VEGF ricombinante di ratto (rrVEGF, 0,17 mg / kg e 5 mg / kg) o PBS. Gli animali sono stati sacrificati post-chirurgico 8 ore per esaminare l&#39;attivazione della via VEGF. La procedura chirurgica non ha influenzato la morfologia del rene perfuso (Figura 1A) rispetto al controllo (Figura 1B), come mostrato da H &amp; E colorazione. Mentre Sirius colorazione rossa non ha mostrato alcun aumento nella deposizione...

Watch this Scientific Journal Video about Intravascular Delivery of Biologics to the Rat Kidney at JoVE.com

Intravascular Delivery of Biologics to the Rat Kidney

La somministrazione di farmaci per il recupero della funzione renale richiede il controllo della localizzazione e distribuzione del composto terapeutico. Qui, descriviamo in dettaglio una semplice tecnica per la consegna intrarenale di farmaci nei ratti. Questa procedura può essere eseguita facilmente senza mortalità ed elevata riproducibilità.

Consegna intravascolare di Biologics al rene di ratto

The renal microvascular compartment plays an important role in the progression of kidney disease and hypertension, leading to the development of End Stage ...

intravascular-delivery-of-biologics-to-the-rat-kidney

Research

JoVE Journal

Medicine

7.4K Views.  Mayo Clinic.  La somministrazione di farmaci per il recupero della funzione renale richiede il controllo della localizzazione e distribuzione del composto terapeutico. Qui, descriviamo in dettaglio una semplice tecnica per la consegna intrarenale di farmaci nei ratti. Questa procedura può essere eseguita facilmente senza mortalità ed elevata riproducibilità. 

Video: Intravascular Delivery of Biologics to the Rat Kidney

Slow-release Drug Delivery through Elvax 40W to the Rat Retina: Implications for the Treatment of Chronic Conditions

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these diseases. Chronic retinal diseases such as retinal oedema or neovascularization usually require multiple intraocular injections to effectively treat the condition. However, the risks associated with these injections increase with repeated delivery of the drug. Therefore, alternative delivery methods need to be established in order to minimize the risks of reinjection. Several other investigations have developed methods to deliver drugs over extended time, through materials capable of releasing chemicals slowly into the eye. In this investigation, we outline the use of Elvax 40W, a copolymer resin, to act as a vehicle for drug delivery to the adult rat retina. The resin is made and loaded with the drug. The drug-resin complex is then implanted into the vitreous cavity, where it will slowly release the drug over time. This method was tested using 2-amino-4-phosphonobutyrate (APB), a glutamate analogue that blocks the light response of the retina. It was demonstrated that the APB was slowly released from the resin, and was able to block the retinal response by 7 days after implantation. This indicates that slow-release drug delivery using this copolymer resin is effective for treating the retina, and could be used therapeutically with further testing.

This paper details how Elvax 40W can be used as a slow-release method for drug delivery to the adult rat retina. The protocol for preparing, loading, and delivering the drug-resin complex to the eye is described.

Lento rilascio Drug Delivery attraverso Elvax 40W al Rat Retina: Implicazioni per il trattamento di condizioni croniche

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these ...

Ricerca

Medicina

Mouse Kidney Transplantation: Models of Allograft Rejection

Rejection of the transplanted kidney in humans is still a major cause of morbidity and mortality. The mouse model of renal transplantation closely replicates both the technical and pathological processes that occur in human renal transplantation. Although mouse models of allogeneic rejection in organs other than the kidney exist, and are more technically feasible, there is evidence that different organs elicit disparate rejection modes and dynamics, for instance the time course of rejection in cardiac and renal allograft differs significantly in certain strain combinations. This model is an attractive tool for many reasons despite its technical challenges. As inbred mouse strain haplotypes are well characterized it is possible to choose donor and recipient combinations to model acute allograft rejection by transplanting across MHC class I and II loci. Conversely by transplanting between strains with similar haplotypes a chronic process can be elicited were the allograft kidney develops interstitial fibrosis and tubular atrophy. We have modified the surgical technique to reduce operating time and improve ease of surgery, however a learning curve still needs to be overcome in order to faithfully replicate the model. This study will provide key points in the surgical procedure and aid the process of establishing this technique.

Here, we present a protocol to study the immunology of rejection. The surgical model presented reports a short operating time and a concise technique. Depending on the donor-recipient strain combination, the transplanted kidney may develop acute cellular rejection or chronic allograft damage, defined by interstitial fibrosis and tubular atrophy.

Mouse trapianto renale: Modelli di Allograft Rifiuto

Rejection of the transplanted kidney in humans is still a major cause of morbidity and mortality. The mouse model of renal transplantation closely ...

Normothermic Ex Vivo Kidney Perfusion for the Preservation of Kidney Grafts prior to Transplantation

Kidney transplantation has become a well-established treatment option for patients with end-stage renal failure. The persisting organ shortage remains a serious problem. Therefore, the acceptance criteria for organ donors have been extended leading to the usage of marginal kidney grafts. These marginal organs tolerate cold storage poorly resulting in increased preservation injury and higher rates of delayed graft function. To overcome the limitations of cold storage, extensive research is focused on alternative normothermic preservation methods.
Ex vivo normothermic organ perfusion is an innovative preservation technique. The first experimental and clinical trials for ex vivo lung, liver, and kidney perfusions demonstrated favorable outcomes.
In addition to the reduction of cold ischemic injury, the method of normothermic kidney storage offers the opportunity for organ assessment and repair. This manuscript provides information about kidney retrieval, organ preservation techniques, and isolated ex vivo normothermic kidney perfusion (NEVKP) in a porcine model. Surgical techniques, set up for the perfusion solution and the circuit, potential assessment options, and representative results are demonstrated.

Normothermic Ex Vivo Kidney Perfusion for the Preservation of Kidney Grafts prior to Transplantation

The severe organ shortage has resulted in increased use of marginal kidney grafts for transplantation. This has triggered interest in alternative storage methods, since marginal grafts especially tolerate cold storage poorly. The technique of normothermic ex vivo kidney perfusion (NEVKP) represents a novel preservation method for kidney grafts prior to &#160;transplantation.

Normotermica<em&gt; Ex Vivo</em&gt; Rene perfusione per la Preservazione della Kidney Innesti prima del trapianto

Kidney transplantation has become a well-established treatment option for patients with end-stage renal failure. The persisting organ shortage remains a ...

Intraluminal Drug Delivery to the Mouse Arteriovenous Fistula Endothelium

Delivery of therapeutic agents to enhance arteriovenous fistula (AVF) maturation can be administered either via intraluminal or external routes. The simple murine AVF model was combined with intraluminal administration of drug solution to the venous endothelium at the same time as fistula creation. Technical aspects of this model are discussed. Under general anesthesia, an abdominal incision is made and the aorta and inferior vena cava (IVC) are exposed. The infra-renal aorta and IVC are dissected for clamping. After proximal and distal clamping, the puncture site is exposed and a 25 G needle is used to puncture both walls of the aorta and into the IVC. Immediately after the puncture, a reporter gene-expressing viral vector was infused in the IVC via the same needle, followed by 15 min of incubation. The intraluminal administration method enabled more robust viral gene delivery to the venous endothelium compared to administration by the external route. This novel method of delivery will facilitate studies that explore the role of the endothelium in AVF maturation and enable intraluminal drug delivery at the time of surgical operation.

After puncturing the aorta through the inferior vena cava (IVC) to create an aorto-caval fistula in the mouse, solution containing a drug is infused into the IVC via the same needle, followed by incubation. This method enables more robust drug delivery to the venous endothelium compared to the external route.

Intraluminale Drug Delivery per il mouse fistola artero-venosa endotelio

Delivery of therapeutic agents to enhance arteriovenous fistula (AVF) maturation can be administered either via intraluminal or external routes. The ...

Method of Direct Segmental Intra-hepatic Delivery Using a Rat Liver Hilar Clamp Model

Major hepatic surgery with inflow occlusion, and liver transplantation, necessitate a period of warm ischemia, and a period of reperfusion leading to ischemia/reperfusion (I/R) injury with myriad negative consequences. Potential I/R injury in marginal organs destined for liver transplantation contributes to the current donor shortage secondary to a decreased organ utilization rate. A significant need exists to explore hepatic I/R injury in order to mediate its impact on graft function in transplantation. Rat liver hilar clamp models are used to investigate the impact of different molecules on hepatic I/R injury. Depending on the model, these molecules have been delivered using inhalation, epidural infusion, intraperitoneal injection, intravenous administration or injection into the peripheral superior mesenteric vein. A rat liver hilar clamp model has been developed for use in studying the impact of pharmacologic molecules in ameliorating I/R injury. The described model for rat liver hilar clamp includes direct cannulation of the portal supply to the ischemic hepatic segment via a side branch of the portal vein, allowing for direct segmental hepatic delivery. Our approach is to induce ischemia in the left lateral and median lobes for 60 min, during which time the substance under study is infused. In this case, pegylated-superoxide dismutase (PEG-SOD), a free radical scavenger, is infused directly into the ischemic segment. This series of experiments demonstrates that infusion of PEG-SOD is protective against hepatic I/R injury. Advantages of this approach include direct injection of the molecule into the ischemic segment with consequent decrease in volume of distribution and reduction in systemic side effects.

A unique rat liver hilar clamp model was developed for studying the impact of pharmacologic molecules in ameliorating ischemia-reperfusion injury. This model includes direct cannulation of the portal supply to the ischemic liver segment via a branch of the portal vein, allowing for direct hepatic delivery.

Metodo di consegna diretta segmentale intra-epatico utilizzando un modello di fegato di ratto Hilar morsetto

Major hepatic surgery with inflow occlusion, and liver transplantation, necessitate a period of warm ischemia, and a period of reperfusion leading to ...

Surgical Labyrinthectomy of the Rat to Study the Vestibular System

To study the vestibular system or the vestibular compensation process, a number of methods have been developed to cause vestibular damage, including surgical or chemical labyrinthectomy and vestibular neurectomy. Surgical labyrinthectomy is a relatively simple, reliable, and rapid method. Here, we describe the surgical technique for rat labyrinthectomy. A postauricular incision is made under general anesthesia to expose the external auditory canal and the tympanic membrane, after which the tympanic membrane and the ossicles are removed without the stapes. The stapes artery, which is located between the stapes and the oval window, is a vulnerable structure and must be preserved to obtain a clear surgical field. A hole to fenestrate the vestibule is made with a 2.1-mm drill bur superior to the stapes. Then, 100% ethanol is injected through this hole and aspirated several times. Meticulous dissection under a microscope and careful bleeding control are essential to obtain reliable results. Symptoms of vestibular loss, such as nystagmus, head tilting, and a rolling motion, are seen immediately after surgery. The rotarod or rotation chair test can be used to objectively and quantitatively evaluate the vestibular function.

This protocol describes the surgical labyrinthectomy of a rat, which is a useful method for studying the vestibular system.

Labyrinthectomy chirurgica del ratto per studiare il sistema vestibolare

To study the vestibular system or the vestibular compensation process, a number of methods have been developed to cause vestibular damage, including ...

A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition

Limited evidence exists to precisely estimate efficacy and safety differences between parenteral nutrition (PN) prepared using olive-oil-based three-chamber bags (3CBs) and soybean-oil-based compounded bags (CoBs) in hospitalized adult patients. We designed a multicenter, randomized, prospective, open-label, noninferiority protocol to compare the efficacy, safety, and distribution of olive-oil-based 3CBs and soybean-oil-based CoB formulations in adult Chinese patients requiring PN during surgical intervention. Subjects were randomized to receive either one of the study treatments using an interactive voice or web-based recognition system in accordance with the randomization code. Randomization was further stratified based on the study site and surgical category. Both treatment groups received similar amounts of calories and protein. In addition, the two study treatments contained a similar composition of the amino-acid component. The only difference between the two PN formulations was the lipid constitution. The duration of administration of study treatments was a minimum of 5 days up to a maximum of 14 days after the surgical procedure. The primary efficacy endpoint was serum prealbumin levels on day 5 of the study. Noninferiority was proved if the anti-log of the lower bound of the 95% confidence interval (CI) of the treatment difference was at least 0.80. Other efficacy measures included treatment preparation time; duration to achieve tolerability of oral nutrition; associated infectious complications; length of hospitalization; and laboratory assessment of markers of nutrition, inflammation, metabolism, and oxidative stress. A total of 458 patients were enrolled in the study. The results showed that olive-oil-based 3CBs were non-inferior to soybean-based CoBs, besides being well tolerated. The infection rate was found to be significantly lower in the olive-oil-based 3CB group. Thus, this study may be used as a reference for future research on lipid emulsion and 3CBs.

Here, we present a protocol for a study comparing the efficacy, safety, and delivery of olive-oil-based 3CB and soybean-oil-based CoB formulations in adults requiring parenteral nutrition. The results revealed that olive-oil-based 3CBs is non-inferior and well tolerated compared to soybean formulations.

Uno studio clinico che valuta la sicurezza, l'efficacia e la consegna di sacchetti a tre camere a base di olio d'oliva per la nutrizione parenterale

Limited evidence exists to precisely estimate efficacy and safety differences between parenteral nutrition (PN) prepared using olive-oil-based ...

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.

Un metodo efficiente di setacciatura per isolare i Glomeruli intatti dal rene di ratto adulto.

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

Orthotopic Rat Kidney Transplantation: A Novel and Simplified Surgical Approach

Kidney transplantation offers increased survival rates and improved quality of life for patients with end-stage renal disease, as compared to any type of renal replacement therapy. Over the past few decades, the rat kidney transplantation model has been used to study the immunological phenomena of rejection and tolerance. This model has become an indispensable tool to test new immunomodulatory pharmaceuticals and regimens prior to proceeding with expensive preclinical large animal studies.
This protocol provides a detailed overview of how to reliably perform orthotopic kidney transplantation in rats. This protocol includes three distinctive steps that increase the probability of success: perfusion of the donor kidney by flushing through the portal vein and the use of a cuff system to anastomose the renal veins and ureters, thereby decreasing cold and warm ischemia times. Using this technique, we have achieved survival rates beyond 6 months with normal serum creatinine in animals with syngeneic or tolerant kidney transplants. Depending on the aim of the study, this model can be modified by pre- or posttransplant treatments to study the acute, chronic, cellular, or antibody-mediated rejection. It is a reproducible, reliable, and cost-effective animal model to study different aspects of kidney transplantation.

The purpose of this manuscript and protocol is to explain and demonstrate in detail the surgical procedure of orthotopic kidney transplantation in rats. This method is simplified to achieve the correct perfusion of the donor kidney and shorten the reperfusion time by using the venous and ureteral cuff anastomosis technique.

Trapianto di rene ortotopico ratto: un nuovo approccio chirurgico semplificato

Kidney transplantation offers increased survival rates and improved quality of life for patients with end-stage renal disease, as compared to any type of ...

Intratracheal Administration of Dry Powder Formulation in Mice

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper introduces a noninvasive method of intratracheal delivery of dry powder formulation in mice. A dry powder loading device that consists of a 200 &#181;L gel loading pipette tip connected to an 1 mL syringe via a three-way stopcock is presented. A small amount of dry powder (1-2 mg) is loaded into the pipette tip and dispersed by 0.6 mL of air in the syringe. Because pipette tips are disposable and inexpensive, different dry powder formulations can be loaded into different tips in advance. Various formulations can be evaluated in the same animal experiment without device cleaning and dose refilling, thereby saving time and eliminating the risk of cross-contamination from residual powder. The extent of powder dispersion can be inspected by the amount of powder remaining in the pipette tip. A protocol of intubation in mouse with a custom-made light source and a guiding cannula is included. Proper intubation is one of the key factors that influences the intratracheal delivery of dry powder formulation to the deep lung region of the mouse.

Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is presented.

Somministrazione intratracheale della formulazione di polvere secca nei topi

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper ...