La source de financement pour la démonstration de laboratoire était NIGMS subvention: GM077119. Nous remercions le Dr Joseph R. Haywood et le Dr Peter Cobbett pour leur soutien de la Couse court intégrative et orgue Systems pharmacologie. Nous remercions également Mme Hannah Garver pour son soutien technique de la démonstration de laboratoire.

Avant toute procédure d&#39;animaux, les soins des animaux et l&#39;utilisation comité institutionnel (IACUC) doit approuver le protocole. Ce protocole a été approuvé par l&#39;Université Michigan State IACUC. 1. Préparation pré-lab de Solution FITC-inuline <ol><li> Chaud 20 ml d&#39;une solution saline à 70 ° C et agiter lentement à 100 mg de FITC-inuline (5 mg / ml de FITC-inuline) jusqu&#39;à ce que toute l&#39;inuline se dissout. </li><li> Solution refroidir à température ambiante et ajouter 800 mg d&#39;albumine de sérum bovin (40 mg / ml de BSA, de la poudre lyophilisée, essentiellement globuline libre, endotoxine faible, ≥98% de pureté par électrophorèse sur gel d&#39;agarose). </li><li> Filtrer la solution inuline-BSA avec du papier filtre (grade 1). Placer la solution filtrée dans une seringue de 20 ml avec un filtre seringue pointe (0,2 um) et couvrir de papier d&#39;aluminium pour protéger de la lumière. </li></ol> 2. anesthésie et la chirurgie <ol><li> Placez le rat dans une chambre d&#39;induction rempli avec 5% d&#39;isoflurane pour induire une anesthésie. bod d&#39;enregistrementpoids y (250-350 g) et de placer le rat sur une plate-forme chirurgicale chauffé conçu pour maintenir 37 ° C la température du corps pendant toute l&#39;expérience. Sécuriser doucement le rat à la plate-forme avec la bande de laboratoire sur les pattes. Maintenir l&#39;anesthésie avec 1-2% d&#39;isoflurane avec qualité médicale 100% O 2 au taux de 0,8-1,0 L / min de débit d&#39;air. </li><li> Insérer un cathéter conique (pointe de OD intravasculaire, 2.7f) dans l&#39;artère fémorale pour la pression artérielle et la surveillance de la fréquence cardiaque, et le prélèvement de sang. </li><li> Insérer un cathéter (PE-50) dans la veine fémorale pour l&#39;injection d&#39;inuline. Fixez le cathéter aux tissus de soie tressée 5-O suture chirurgicale 6 environnante. </li><li> Attacher le cathéter artériel à un transducteur de pression à jauge de contrainte. Enregistrez la pression artérielle et le rythme cardiaque en utilisant le logiciel d&#39;acquisition de données et l&#39;affichage sur un écran d&#39;ordinateur en temps réel. Cette technique est démontrée en détail sur la vidéo 6. </li><li> Exposer la vessie par une incision sus-pubienne. Coupez un petittrou dans la pointe de la vessie et d&#39;insérer une canule (PE-190) avec une chaleur évasées pointe intérieur de la vessie pour la collecte d&#39;urine. Fixez la canule à la vessie avec une suture en bourse. </li></ol> 3. L&#39;urine et de prélèvement sanguin <ol><li> Placer la seringue de FITC-inuline dans une pompe à seringue avec un débit fixé de 1 ml / h pour 100 g de poids corporel (3 ml / h pour un rat pesant 300 g). Fixer la seringue au cathéter de la veine fémorale. Lancer la perfusion de l&#39;inuline et de permettre une période d&#39;équilibrage de 1-2 h. Gardez seringue recouverts d&#39;une feuille de protéger de la lumière. </li><li> Déterminer si le taux d&#39;écoulement de l&#39;urine est stable et appropriée pour l&#39;analyse de l&#39;échantillon (20 pl / min) en recueillant un échantillon d&#39;urine dans un flacon pré-pesé collecte pendant une période de 10 min. Déterminer le volume d&#39;urine par gravimétrie avec une échelle numérique. Un volume d&#39;urine pendant une période adéquate de collecte de 10 min est de 0,2 ml. Continuer à prélever des échantillons d&#39;urine jusqu&#39;à ce que deux collections consécutives indiquent un taux de 20 pi / m d&#39;écoulement d&#39;urineou plus. </li><li> Échantillons de pré-drogues <ol><li> Prélever un échantillon d&#39;urine pendant une période de 20 min. Prélever un échantillon de sang (0,5 ml) à partir du cathéter artériel au point milieu de la période de collecte d&#39;urine. Soyez prudent pour dégager complètement le cathéter artériel de solution saline avant de recueillir un échantillon de sang dans un flacon de collection contenant 1 U héparine. Utiliser les flacons de collecte avec des marques de volume pour faciliter la collecte de 0,5 ml de sang artériel. </li><li> Rincer le cathéter artériel avec une solution saline à l&#39;héparine (20 U / ml) pour effacer le cathéter de sang (env. 0,1 ml). La longueur du cathéter artériel doit être aussi court que possible afin de limiter le volume de solution saline à l&#39;héparine requis pour rincer. Remarque: des échantillons de sang dilué produisent des calculs inexacts de DFG et l&#39;excrétion fractionnaire de Na et K. </li><li> Attendre 10 min, et répéter la collecte de l&#39;urine une seconde pré-médicament et de l&#39;échantillon de sang. </li></ol></li><li> Après la collecte de deux échantillons de pré-drogue, administrer un diurétique drug, furosémide (10 mg / kg), par l&#39;intermédiaire du cathéter artériel. Rincer le cathéter artériel avec une solution saline héparinée pour effacer le cathéter de médicament. Faire attention à empêcher l&#39;injection d&#39;air à travers le cathéter artériel. Notez l&#39;heure de l&#39;injection de furosémide. </li><li> Les échantillons post-médicaments: A chacun des points dans le temps 3 ci-dessous, de recueillir un échantillon d&#39;urine pendant une période de collecte de 10 min, et un échantillon de sang (0,5 ml) au milieu de la période de collecte d&#39;urine. <ol><li> Pour l&#39;échantillon post-Drug 1 - recueillir cinq minutes après le furosémide. </li><li> Pour l&#39;échantillon post-Drug 2 - recueillir dix minutes après le furosémide. </li><li> Pour l&#39;échantillon post-Drug 3 - recueillir quinze minutes après le furosémide. </li></ol></li><li> Lorsque tous les échantillons ont été collectés, euthanasier le rat conformément aux procédures institutionnelles par thoracotomie et l&#39;ablation du cœur. Retirez les deux reins. Décapsuler (retirer la membrane entourant) et efface les reins à éliminer l&#39;excès de sang. Peser les reins. </li></ol><ol><li> Mesurer tous les volumes d&#39;échantillon d&#39;urine par gravimétrie avec une balance numérique, et des poids records. </li><li> Centrifugeuse échantillons de sang entier avec une centrifugeuse de table (1800 xg) pour séparer le plasma. Transférer des échantillons de plasma de petits flacons étiquetés. </li><li> Analyser concentrations de Na et K dans les échantillons d&#39;urine et de plasma avec un analyseur de sodium / potassium. </li><li> Mesure de FITC-inuline dans le plasma et l&#39;urine <ol><li> Diluer l&#39;urine pré-drogue (de 1: 200 à 1: 400), et l&#39;urine post-drogue (1:10) avec un tampon HEPES (500 mM, pH 7,4). </li><li> Ajouter 40 pi de pi étalon ou d&#39;échantillon et 60 de tampon HEPES dans une plaque de 96 puits (un échantillon par puits) et de permettre à mélanger pendant 10 min tout recouvert d&#39;une feuille d&#39;aluminium. </li><li> Générer une courbe d&#39;étalonnage pour FITC-inuline pour des concentrations de 6,25, 12,5, 25, 50, 100, 200, 400 ug / ml (Figure 1). Déterminer FITC-inuline fluorescence dans les échantillons et les normes en utilisant un lecteur de microplaques avec son excitations et d&#39;émission des longueurs d&#39;onde de 485 nm et 538, respectivement. </li><li> Monter les valeurs fluorescents pour les normes à une fonction logistique analyse de régression de 4 paramter. Les paramètres de la fonction de régression sont utilisés pour calculer la concentration FITC-inuline dans des échantillons de plasma et d&#39;urine (tableau 1). </li></ol></li></ol> 5. Analyse post-laboratoire des résultats: Calculs <ol><li> Calculer urine Débit (UV; ml / min): [volume d&#39;urine recueillis (ml)] ÷ [moment de la collecte (min)] </li><li> Calculer débit de filtration glomérulaire (GFR; ml / min): [concentration d&#39;inuline urine (pg / ml) x UV (ml / min)] ÷ [Plasma inuline conc. (Ug / ml)] </li><li> Calculer la charge filtrée de sodium (pmol / min): concentration en sodium du plasma (umoles / ml) x DFG (ml / min) </li><li> Calculer l&#39;excrétion de sodium Taux (U Na V; pmol / min): la concentration de sodium dans l&#39;urine (pmol / ml) x UV (ml / min) </li><li> Calculer fractionnaire excrétion de sodium (FE Na;%): [U Na V (pmol / min)] ÷ [Charge de sodium filtré (pmol / min)] x 100 </li><li> Calculer la charge filtrée potassium (pmol / min): Plasma concentration de potassium (umol / ml) x DFG (ml / min) </li><li> Calculer excrétion de potassium Taux (U K V; pmol / min): la concentration de potassium dans l&#39;urine (pmol / ml) x UV (ml / min) </li><li> Calculer fractionnaire excrétion de potassium (K FE;%): [U K V (pmol / min)] ÷ [Charge de potassium filtrée (pmol / min)] x 100 </li></ol>

<ol>
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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+renal+function+in+chronic+renal+disease.">Measurement of renal function in chronic renal disease.</a> Kidney International. 38 (1), 167-184 (1990).</li><li>Thurau, K., Valtin, H., Schnermann, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kidney.">Kidney.</a> Annual Review of Physiology. 30, 441-524 (1968).</li><li>Shannon, J. A., Smith, H. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+excretion+of+inulin,+xylose,+and+urea+by+normal+and+phoriziniaed+man.">The excretion of inulin, xylose, and urea by normal and phoriziniaed man.</a> Journal of Clinical Investigation. 14, 393-401 (1935).</li><li>Jespersen, B., Knupp, L., Northcott, C. 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(59), (2012).</li><li>Sterner, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determining+'true'+glomerular+filtration+rate+in+healthy+adults+using+infusion+of+inulin+and+comparing+it+with+values+obtained+using+other+clearance+techniques+or+predictive+equations.">Determining 'true' glomerular filtration rate in healthy adults using infusion of inulin and comparing it with values obtained using other clearance techniques or predictive equations.</a> Scandinavian Journal of Urology and Nephrology. 42, 278-285 (2008).</li><li>Toto, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conventional+measurement+of+renal+function+utilizing+serum+creatinine,+creatinine+clearance,+inulin+and+para-aminohippuric+acid+clearance.">Conventional measurement of renal function utilizing serum creatinine, creatinine clearance, inulin and para-aminohippuric acid clearance.</a> Current Opinion in Nephrology and Hypertension. 4 (6), 505-509 (1995).</li><li>Matavelli, L. C., Kadowitz, P. J., Navar, L. G., Majid, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Renal+hemodynamic+and+excretory+responses+to+intra-arterial+infusion+of+peroxynitrite+in+anesthetized+rats.">Renal hemodynamic and excretory responses to intra-arterial infusion of peroxynitrite in anesthetized rats.</a> Americam Journal of Physiology. 296, F170-F176 (2009).</li><li>Davidson, W. D., Sackner, 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=Simplification+of+the+anthrone+method+for+the+determination+of+inulin+in+clearance+studies.">Simplification of the anthrone method for the determination of inulin in clearance studies.</a> Journal of Laboratory, &amp; Clinical Medicine. 62, 351-356 (1963).</li><li>Symes, A. L., Gault, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assay+of+inulin+in+tissues+using+anthrone.">Assay of inulin in tissues using anthrone.</a> Clinical Biochemistry. 8 (1), 67-70 (1975).</li><li>Shalmi, M., Lunau, H. E., Petersen, J. S., Bak, M., Christensen, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Suitability+of+tritiated+inulin+for+determination+of+glomerular+filtration+rate.">Suitability of tritiated inulin for determination of glomerular filtration rate.</a> Americam Journal of Physiology. 260 (2 Pt 2), F283-F289 (1991).</li><li>Denton, K. M., Anderson, W. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glomerular+untrafiltration+in+rabbits+with+superficial+glomeruli.">Glomerular untrafiltration in rabbits with superficial glomeruli.</a> EUropean Journal of Physiology. 419 (3-4), 235-242 (1991).</li><li>Jobin, J., Bonjour, J. -. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+glomerular+filtration+rate+in+conscious+unrestrained+rats+with+inulin+infused+by+implanted+osmotic+pumps.">Measurement of glomerular filtration rate in conscious unrestrained rats with inulin infused by implanted osmotic pumps.</a> Americam Journal of Physiology. 248 (5 Pt 2), F734-F738 (1985).</li><li>Lorenz, J. N., Gruenstein, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple,+nonradioactive+method+for+evaluating+single-nephron+filtration+rate+using+FITC-inulin.">A simple, nonradioactive method for evaluating single-nephron filtration rate using FITC-inulin.</a> Americam Journal of Physiology. 276 (1 Pt 2), F172-F177 (1999).</li><li>Qi, Z., 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=Serial+determination+of+glomerular+filtration+rate+in+conscious+mice+using+FITC-inulin+clearance.">Serial determination of glomerular filtration rate in conscious mice using FITC-inulin clearance.</a> Americam Journal of Physiology. 286 (3), F590-F596 (2004).</li><li>Bivona, B. J., Park, S., Harrison-Bernard, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glomerular+filtration+rate+determinations+in+conscious+type+II+diabetic+mice.">Glomerular filtration rate determinations in conscious type II diabetic mice.</a> Americam Journal of Physiology. 300 (3), F618-F625 (2011).</li><li>Rosen, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+anaesthesia+and+surgery+on+renal+hemodynamics.">Effects of anaesthesia and surgery on renal hemodynamics.</a> British Journal of Anesthesiology. 44, 252-258 (1972).</li><li>Cousins, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anesthesia+and+the+kidney.">Anesthesia and the kidney.</a> Anaesthesia and intensive care. 11 (4), 292-320 (1983).</li><li>Walter, S. J., Zewde, T., Shirley, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+anaesthesia+and+standard+clearance+procedures+on+renal+function+in+the+rat.">The effect of anaesthesia and standard clearance procedures on renal function in the rat.</a> Quarterly Journal of Experimental Physiology. 74, 805-812 (1989).</li><li>Rieg, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+high-throughput+method+for+measurement+of+glomerular+filtration+rate+in+conscious+mice.">A high-throughput method for measurement of glomerular filtration rate in conscious mice.</a> Journal of Visualized Experiments. (75), (2013).</li></ol>

Les auteurs déclarent qu&#39;ils ont aucun intérêt financier concurrentes. Les opinions ou affirmations contenues dans ce document sont les opinions personnelles de l&#39;auteur et ne doivent pas être interprétées comme fonctionnaire ou comme reflétant les vues du Département de l&#39;armée ou du ministère de la Défense.

Un marqueur approprié pour la mesure de GFR doit répondre à quatre critères: être filtré librement le glomérule, non liée aux protéines plasmatiques, et ni être absorbé ni sécrétée dans le néphron. L&#39;inuline est un polymère de fructose qui satisfait à ces critères. En conséquence, la clairance rénale de l&#39;inuline est considéré comme l&#39;étalon-or pour mesurer GFR 7. La technique démontrée représente l&#39;approche traditionnelle de la détermination de la clairance rénale ...

The most important function of the kidney is the homeostatic regulation of extracellular water and electrolyte content. The kidneys closely regulate extracellular water, sodium (Na) and potassium (K) to maintain normal physiological levels. Disturbances in renal function can result in serious metabolic disorders which can be fatal. The basic renal process occurs in the nephron and begins with the filtration of plasma at the glomerulus and ends with the excretion of urine. Other processes that determine the final concentration of water, Na and K in the urine are secretion and reabsorption within the nephron. Measurements of glomerular filtration rate (GFR) and the fractional excretion of Na and K are critical in assessing renal function in health and disease. The reader is referred to previously published review articles and textbooks for a more thorough discussion of kidney function1-4. 
GFR can be measured as the steady state renal clearance of inulin which is filtered at the glomerulus, but not secreted or reabsorbed along the nephron5. While this technique requires anesthesia, surgical preparation, and a terminal experiment, it is considered the gold standard of GFR measurement. Using inulin that is tagged with fluorescein-isothiocyanate (FITC), plasma and urine concentration of FITC-inulin can be easily measured in small volumes and used to calculate GFR during multiple time points of an experiment. The fractional excretion of Na and K can be determined from the concentration of Na and K in plasma and urine. 
The conceptual understanding of how to measure renal function can easily be demonstrated in a short lab designed to allow students to actively participate in some aspects of the experiment. This video depicts the pre-lab preparation, the renal function demonstration, and the post-lab evaluation of results. The surgical techniques necessary for making measurements of GFR are demonstrated in an anesthetized rat. In addition, example calculations for GFR, and the fractional excretion of Na and K are shown before and after administration of a diuretic drug.

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<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>5-0 Braided Silk Surgical Suture</td>
			<td>Surgical Specialties Corp</td>
			<td>SP1033</td>
			<td></td>
		</tr>
		<tr>
			<td>Assay Plate, 96-Well</td>
			<td>Costar&#160;</td>
			<td>3922</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin</td>
			<td>Sigma Chemical Co</td>
			<td>A2934-25G</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>Beckman Coulter</td>
			<td>MicroFuge 18, 357160</td>
			<td></td>
		</tr>
		<tr>
			<td>Conical Sample Tubes</td>
			<td>Dot Scientific Inc.&#160;</td>
			<td>#711-FTG</td>
			<td></td>
		</tr>
		<tr>
			<td>Cotton Tipped Applicators</td>
			<td>Solon Manufacturing Co</td>
			<td>56200</td>
			<td></td>
		</tr>
		<tr>
			<td>Data Acquisition Software</td>
			<td>ADInstruments</td>
			<td>LabChart Pro 7.0</td>
			<td></td>
		</tr>
		<tr>
			<td>Digital Scale&#160;</td>
			<td>Denver Instrument</td>
			<td>APX-4001</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC-Inulin</td>
			<td>Sigma Chemical Co</td>
			<td>F3272-1G</td>
			<td></td>
		</tr>
		<tr>
			<td>Gauze Sponges</td>
			<td>Covidien</td>
			<td>2146</td>
			<td></td>
		</tr>
		<tr>
			<td>Heated Surgical Bed</td>
			<td>EZ-Anesthesia</td>
			<td>EZ-212</td>
			<td></td>
		</tr>
		<tr>
			<td>Heparin</td>
			<td>Sagnet</td>
			<td>NDC 25021-402-10</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>Sigma Chemical Co</td>
			<td>H3375</td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Abbott Animal Health</td>
			<td>IsoFlo, 5260-04-05</td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane Vaporizer</td>
			<td>EZ-Anesthesia</td>
			<td>EZ-190F</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro Dissecting Forceps</td>
			<td>Biomedical Research Instruments Inc.</td>
			<td>70-1020</td>
			<td></td>
		</tr>
		<tr>
			<td>Microplate Reader - Fluoroskan</td>
			<td>ThermoScientific</td>
			<td>Ascent FL, 5210460</td>
			<td></td>
		</tr>
		<tr>
			<td>NOVA 5+ Sodium/Potassium Analyzer</td>
			<td>NOVA BioMedical</td>
			<td>14156</td>
			<td></td>
		</tr>
		<tr>
			<td>Olsen-Hegar Needle Holders with Scissors</td>
			<td>Fine Science Tools</td>
			<td>12002-12</td>
			<td></td>
		</tr>
		<tr>
			<td>PE-190 (for bladder catheter)</td>
			<td>BD Medical</td>
			<td>427435</td>
			<td></td>
		</tr>
		<tr>
			<td>Pressure Transducer&#160;</td>
			<td>ADInstruments</td>
			<td>MLT1199</td>
			<td></td>
		</tr>
		<tr>
			<td>Pyrex Culture Tubes</td>
			<td>Corning Inc.</td>
			<td>99445-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat Femoral Tapered Artery Catheter</td>
			<td>Strategic Applications Inc.</td>
			<td>RFA-01</td>
			<td></td>
		</tr>
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			<td>Salix Furosemide 5%</td>
			<td>Intervet</td>
			<td>#34-478</td>
			<td></td>
		</tr>
		<tr>
			<td>Strabismus Scissors</td>
			<td>Fine Science Tools</td>
			<td>14075-11</td>
			<td></td>
		</tr>
		<tr>
			<td>Student Surgical Scissors</td>
			<td>Fine Science Tools</td>
			<td>91402-12</td>
			<td></td>
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		<tr>
			<td>Surgical Gloves</td>
			<td>Kimberly-Clark</td>
			<td>Sterling Nitrile Gloves</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe pump</td>
			<td>Razel Scientific</td>
			<td>R99-E</td>
			<td></td>
		</tr>
		<tr>
			<td>Tissue Forceps</td>
			<td>Fine Science Tools</td>
			<td>91121-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Tissue Scissors</td>
			<td>George Tiemann&#160; Co</td>
			<td>105-420</td>
			<td></td>
		</tr>
	</tbody>
</table>
5-0 Braided Silk Surgical Suture Surgical Specialties Corp SP1033 Assay Plate, 96-Well Costar&#160; 3922 Bovine Serum Albumin Sigma Chemical Co A2934-25G Centrifuge Beckman Coulter MicroFuge 18, 357160 Conical Sample Tubes Dot Scientific Inc.&#160; #711-FTG Cotton Tipped Applicators Solon Manufacturing Co 56200 Data Acquisition Software ADInstruments LabChart Pro 7.0 Digital Scale&#160; Denver Instrument APX-4001 FITC-Inulin Sigma Chemical Co F3272-1G Gauze Sponges Covidien 2146 Heated Surgical Bed EZ-Anesthesia EZ-212 Heparin Sagnet NDC 25021-402-10 HEPES Sigma Chemical Co H3375 Isoflurane Abbott Animal Health IsoFlo, 5260-04-05 Isoflurane Vaporizer EZ-Anesthesia EZ-190F Micro Dissecting Forceps Biomedical Research Instruments Inc. 70-1020 Microplate Reader - Fluoroskan ThermoScientific Ascent FL, 5210460 NOVA 5+ Sodium/Potassium Analyzer NOVA BioMedical 14156 Olsen-Hegar Needle Holders with Scissors Fine Science Tools 12002-12 PE-190 (for bladder catheter) BD Medical 427435 Pressure Transducer&#160; ADInstruments MLT1199 Pyrex Culture Tubes Corning Inc. 99445-12 Rat Femoral Tapered Artery Catheter Strategic Applications Inc. RFA-01 Salix Furosemide 5% Intervet #34-478 Strabismus Scissors Fine Science Tools 14075-11 Student Surgical Scissors Fine Science Tools 91402-12 Surgical Gloves Kimberly-Clark Sterling Nitrile Gloves Syringe pump Razel Scientific R99-E Tissue Forceps Fine Science Tools 91121-12 Tissue Scissors George Tiemann&#160; Co 105-420

physiology lab demonstration: glomerular filtration rate in a rat

Measurements of glomerular filtration rate (GFR), and the fractional excretion of sodium (Na) and potassium (K) are critical in assessing renal function in health and disease. GFR is measured as the steady state renal clearance of inulin which is filtered at the glomerulus, but not secreted or reabsorbed along the nephron. The fractional excretion of Na and K can be determined from the concentration of Na and K in plasma and urine. The renal clearance of inulin can be demonstrated in an anesthetized animal which has catheters in the femoral artery, femoral vein and bladder. The equipment and supplies used for this procedure are those commonly available in a research core facility, and thus makes this procedure a practical means for measuring renal function. The purpose of this video is to demonstrate the procedures required to perform a lab demonstration in which renal function is assessed before and after a diuretic drug. The presented technique can be utilized to assess renal function in rat models of renal disease.

Le diurétique utilisé dans la démonstration de laboratoire était furosémide qui inhibe très rapidement la réabsorption de Na et K filtré par le rein entraînant une augmentation de Na, K, et l&#39;excrétion de l&#39;eau dans les minutes suivant l&#39;administration du médicament. Par son mécanisme primaire, furosémide devrait avoir des effets minimes sur GFR et la charge filtrée de Na et K, mais va augmenter le flux d&#39;urine et l&#39;excrétion fractionnaire de Na et K. Les r...

Watch this Scientific Journal Video about Physiology Lab Demonstration: Glomerular Filtration Rate in a Rat at JoVE.com

Démonstration en laboratoire de physiologie : taux de filtration glomérulaire chez un rat | Biologie | Vidéo

Physiology Lab Demonstration: Glomerular Filtration Rate in a Rat

The purpose of this protocol is to demonstrate the principles and techniques for measuring and calculating glomerular filtration rate, urine flow rate, and excretion of sodium and potassium in a rat. This demonstration can be used to provide students with an overall conceptual understanding of how to measure renal function.

Laboratoire de Physiologie et de démonstration: taux de filtration glomérulaire dans un Rat

Measurements of glomerular filtration rate (GFR), and the fractional excretion of sodium (Na) and potassium (K) are critical in assessing renal function ...

physiology-lab-demonstration-glomerular-filtration-rate-in-a-rat

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17.2K vues.  U.S. Army Institute of Surgical Research. The purpose of this protocol is to demonstrate the principles and techniques for measuring and calculating glomerular filtration rate, urine flow rate, and excretion of sodium and potassium in a rat. This demonstration can be used to provide students with an overall conceptual understanding of how to measure renal function. 

Vidéo: Physiology Lab Demonstration: Glomerular Filtration Rate in a Rat

Large Volume (20L+) Filtration of Coastal Seawater Samples

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For this method, samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. This video documents large volume (&ge;20 L) filtration of microbial biomass, ranging between 0.22&mu;m and 2.7&mu;m in diameter, from the water column. Two 20L samples can be filtered simultaneously using a single pump unit equipped with four rotating heads. Filtration is done in the field on extended trips, or immediately upon return for day trips. It is important to record the amount of water passing through each sterivex filter unit. To prevent biofilm formation between sampling trips, all filtration equipment must be rinsed with dilute HCl and deionized water and autoclaved immediately after use. This procedure will take approximately 5 hours plus an additional hour for clean up.

Large Volume 20L+ Filtration of Coastal Seawater Samples

This video documents large volume (&ge;20 L) filtration of microbial biomass, ranging between 0.22&mu;m and 2.7&mu;m in diameter, from the water column.

Grand volume (20L +) filtration d&#39;échantillons d&#39;eau de mer côtière

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For this method, ...

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Small Volume (1-3L) Filtration of Coastal Seawater Samples

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For today s demonstration samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. This video documents small volume (~1 L) filtration of microbial biomass from the water column. The protocol is an extension of the large volume sampling protocol described earlier, with one major difference: here, there is no pre-filtration step, so all size classes of biomass are collected down to the 0.22 &mu;m filter cut-off. Samples collected this way are ideal for nucleic acid analysis. The set-up, filtration, and clean-up steps each take about 20-30 minutes. If using two peristaltic pumps simultaneously, up to 8 samples may be filtered at the same time. To prevent biofilm formation between sampling trips, all filtration equipment must be rinsed with dilute HCl and deionized water and autoclaved immediately after use.

Small Volume 1-3L Filtration of Coastal Seawater Samples

This video documents small volume (~1 L) filtration of microbial biomass from the water column.

Petit volume (1-3L) filtration d&#39;échantillons d&#39;eau de mer côtière

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For today s ...

A Video Demonstration of Preserved Piloting by Scent Tracking but Impaired Dead Reckoning After Fimbria-Fornix Lesions in the Rat

Piloting and dead reckoning navigation strategies use very different cue constellations and computational processes (Darwin, 1873; Barlow, 1964; O&#x2019;Keefe and Nadel, 1978; Mittelstaedt and Mittelstaedt, 1980; Landeau et al., 1984; Etienne, 1987; Gallistel, 1990;
Maurer and S&#233;guinot, 1995). Piloting requires the use of the relationships between relatively stable external (visual, olfactory, auditory) cues, whereas dead reckoning requires the integration of cues generated by self-movement. Animals obtain self-movement information from vestibular receptors, and possibly muscle and joint receptors, and efference copy of commands that generate movement. An animal may also use the flows of visual, auditory, and olfactory stimuli caused by its movements. Using a piloting strategy an animal can use geometrical calculations to determine directions and distances to places in its environment, whereas using an dead reckoning strategy it can integrate cues generated by its previous movements to return to a just left location. Dead reckoning is colloquially called "sense of direction" and "sense of distance."

Although there is considerable evidence that the hippocampus is involved in piloting (O&#x2019;Keefe and Nadel, 1978; O&#x2019;Keefe and Speakman, 1987), there is also evidence from behavioral (Whishaw et al., 1997; Whishaw and Maaswinkel, 1998; Maaswinkel and Whishaw, 1999), modeling (Samsonovich and McNaughton, 1997), and electrophysiological (O&#x2019;Mare et al., 1994; Sharp et al., 1995; Taube and Burton, 1995; Blair and Sharp, 1996; McNaughton et al., 1996; Wiener, 1996; Golob and Taube, 1997) studies that the hippocampal formation is involved in dead reckoning. The relative contribution of the hippocampus to the two forms of navigation is still uncertain, however. Ordinarily, it is difficult to be certain that an animal is using a piloting versus a dead reckoning strategy because animals are very flexible in their use of strategies and cues (Etienne et al., 1996; Dudchenko et al., 1997; Martin et al., 1997; Maaswinkel and Whishaw, 1999). The objective of the present video demonstrations was to solve the problem of cue specification in order to examine the relative contribution of the hippocampus in the use of these strategies. The rats were trained in a new task in which they followed linear or polygon scented trails to obtain a large food pellet hidden on an open field. Because rats have a proclivity to carry the food back to the refuge, accuracy and the cues used to return to the home base were dependent variables (Whishaw and Tomie, 1997). To force an animal to use a a dead reckoning strategy to reach its refuge with the food, the rats were tested when blindfolded or under infrared light, a spectral wavelength in which they cannot see, and in some experiments the scent trail was additionally removed once an animal reached the food. To examine the relative contribution of the hippocampus, fimbria&#x2013;fornix (FF) lesions, which disrupt information flow in the hippocampal formation (Bland, 1986), impair memory (Gaffan and Gaffan, 1991), and produce spatial deficits (Whishaw and Jarrard, 1995), were used.

In a piloting scent tracking task, the ability of the rats to return to a refuge with food using visual an odor trail or using dead reckoning in infrared light, the integrated record of previous movements, demonstrates that the hippocampus is necessary for dead reckoning.

Une vidéo de démonstration de conserves de pilotage par le suivi parfum, mais avec facultés affaiblies Dead Reckoning Après Fimbria-Fornix lésions chez le rat

Piloting and dead reckoning navigation strategies use very different cue constellations and computational processes (Darwin, 1873; Barlow, 1964; ...

Historical View and Physiology Demonstration at the NMJ of the Crayfish Opener Muscle

Here we present some of the key important discoveries made with the opener neuromuscular (NMJ) preparation of crustaceans and illustrate that there is still much to learn from this model preparation. In understanding the history one can appreciate why even today this NMJ still offers a rich playground to address questions regarding pre- and post-synaptic function and plasticity. The viability and ease of access to the terminal for intracellular as well as extracellular electrophysiology and imaging are significant advantages. The mechanisms behind the modulation of vesicular kinetics and fusion within the high- and low-output terminals are begging for investigation. The preparation also offers a testable model system for computational assessments and manipulations to examine key variables in theoretical models of synaptic function, for example calcium dynamics during short-term facilitation. The synaptic complexity of active zone and statistical nature of quantal release is also an open area for future investigation both experimentally and computationally.

The opener muscle of the crayfish leg is presented for its historical importance and experimental versatility in muscle phenotype, synaptic physiology and plasticity.

Voir historique et démonstration de physiologie à l&#39;JNM du muscle Opener écrevisses

Here we present some of the key important discoveries made with the opener neuromuscular (NMJ) preparation of crustaceans and illustrate that there is ...

Ovariectomy and 17&beta;-estradiol Replacement in Rats and Mice: A Visual Demonstration

Estrogens are a family of female sexual hormones with an exceptionally wide spectrum of effects. When rats and mice are used in estrogen research they are commonly ovariectomized in order to ablate the rapidly cycling hormone production, replacing the 17&beta;-estradiol exogenously. There is, however, lack of consensus regarding how the hormone should be administered to obtain physiological serum concentrations. This is crucial since the 17&beta;-estradiol level/administration method profoundly influences the experimental results1-3. We have in a series of studies characterized the different modes of 17&beta;-estradiol administration, finding that subcutaneous silastic capsules and per-oral nut-cream Nutella are superior to commercially available slow-release pellets (produced by the company Innovative Research of America) and daily injections in terms of producing physiological serum concentrations of 17&beta;-estradiol4-6. Amongst the advantages of the nut-cream method, that previously has been used for buprenorphine administration7, is that when used for estrogen administration it resembles peroral hormone replacement therapy and is non-invasive. The subcutaneous silastic capsules are convenient and produce the most stable serum concentrations. This video article contains step-by-step demonstrations of ovariectomy and 17&beta;-estradiol hormone replacement by silastic capsules and peroral Nutella in rats and mice, followed by a discussion of important aspects of the administration procedures.

Ovariectomy and 17&amp;#946;-estradiol Replacement in Rats and Mice: A Visual Demonstration

Ovariectomy and subsequent replacement of 17&beta;-estradiol by means of silastic capsules and peroral Nutella are demonstrated in rats and mice.

Remplacement ovariectomie et 17β-estradiol chez les rats et les souris: une démonstration visuelle

Estrogens are a family of female sexual hormones with an exceptionally wide spectrum of effects. When rats and mice are used in estrogen research they are ...

A High-throughput Method for Measurement of Glomerular Filtration Rate in Conscious Mice

The measurement of glomerular filtration rate (GFR) is the gold standard in kidney function assessment. Currently, investigators determine GFR by measuring the level of the endogenous biomarker creatinine or exogenously applied radioactive labeled inulin (3H or 14C). Creatinine has the substantial drawback that proximal tubular secretion accounts for ~50% of total renal creatinine excretion and therefore creatinine is not a reliable GFR marker. Depending on the experiment performed, inulin clearance can be determined by an intravenous single bolus injection or continuous infusion (intravenous or osmotic minipump). Both approaches require the collection of plasma or plasma and urine, respectively. Other drawbacks of radioactive labeled inulin include usage of isotopes, time consuming surgical preparation of the animals, and the requirement of a terminal experiment. Here we describe a method which uses a single bolus injection of fluorescein isothiocyanate-(FITC) labeled inulin and the measurement of its fluorescence in 1-2 &mu;l of diluted plasma. By applying a two-compartment model, with 8 blood collections per mouse, it is possible to measure GFR in up to 24 mice per day using a special work-flow protocol. This method only requires brief isoflurane anesthesia with all the blood samples being collected in a non-restrained and awake mouse. Another advantage is that it is possible to follow mice over a period of several months and treatments (i.e. doing paired experiments with dietary changes or drug applications). We hope that this technique of measuring GFR is useful to other investigators studying mouse kidney function and will replace less accurate methods of estimating kidney function, such as plasma creatinine and blood urea nitrogen.

Measurement of glomerular filtration rate (GFR) is the gold standard for kidney function assessment. Here we describe a high-throughput method which allows the determination of GFR in conscious mice by using a single bolus injection, determination of fluorescein isothiocyanate (FITC)-inulin in plasma and calculation of GFR by a two-phase exponential decay model.

Une méthode à haut débit pour la mesure de débit de filtration glomérulaire chez des souris conscientes

The measurement of  glomerular filtration rate (GFR) is the gold standard in kidney function  assessment. Currently, investigators determine GFR by ...

Rapid Isolation And Purification Of Mitochondria For Transplantation By Tissue Dissociation And Differential Filtration

Previously described mitochondrial isolation methods using differential centrifugation and/or Ficoll gradient centrifugation require 60 to 100 min to complete. We describe a method for the rapid isolation of mitochondria from mammalian biopsies using a commercial tissue dissociator and differential filtration. In this protocol, manual homogenization is replaced with the tissue dissociator&#8217;s standardized homogenization cycle. This allows for uniform and consistent homogenization of tissue that is not easily achieved with manual homogenization. Following tissue dissociation, the homogenate is filtered through nylon mesh filters, which eliminate repetitive centrifugation steps. As a result, mitochondrial isolation can be performed in less than 30 min. This isolation protocol yields approximately 2 x 1010 viable and respiration competent mitochondria from 0.18 &#177; 0.04 g (wet weight) tissue sample.

A method for rapid isolation of mitochondria from mammalian tissue biopsies is described. Rat liver or skeletal muscle preparations were homogenized with a commercial tissue dissociator and mitochondria were isolated by differential filtration through nylon mesh filters. Mitochondrial isolation time is &#60;30 min compared to 60 - 100 min using alternative methods.

Isolement rapide et la purification des mitochondries pour la transplantation par la dissociation des tissus et différencié Filtration

Previously described mitochondrial isolation methods using differential centrifugation and/or Ficoll gradient centrifugation require 60 to 100 min to ...

An Experimental and Bioinformatics Protocol for RNA-seq Analyses of Photoperiodic Diapause in the Asian Tiger Mosquito, Aedes albopictus

Photoperiodic diapause is an important adaptation that allows individuals to escape harsh seasonal environments via a series of physiological changes, most notably developmental arrest and reduced metabolism. Global gene expression profiling via RNA-Seq can provide important insights into the transcriptional mechanisms of photoperiodic diapause. The Asian tiger mosquito, Aedes albopictus, is an outstanding organism for studying the transcriptional bases of diapause due to its ease of rearing, easily induced diapause, and the genomic resources available. This manuscript presents a general experimental workflow for identifying diapause-induced transcriptional differences in A. albopictus. Rearing techniques, conditions necessary to induce diapause and non-diapause development, methods to estimate percent diapause in a population, and RNA extraction and integrity assessment for mosquitoes are documented. A workflow to process RNA-Seq data from Illumina sequencers culminates in a list of differentially expressed genes. The representative results demonstrate that this protocol can be used to effectively identify genes differentially regulated at the transcriptional level in A. albopictus due to photoperiodic differences. With modest adjustments, this workflow can be readily adapted to study the transcriptional bases of diapause or other important life history traits in other mosquitoes.

An Experimental and Bioinformatics Protocol for RNA-seq Analyses of Photoperiodic Diapause in the Asian Tiger Mosquito, Aedes albopictus

RNA-Seq analyses are becoming increasingly important for identifying the molecular underpinnings of adaptive traits in non-model organisms. Here, a protocol to identify differentially expressed genes between diapause and non-diapause Aedes albopictus mosquitoes is described, from mosquito rearing, to RNA sequencing and bioinformatics analyses of RNA-Seq data.

Un protocole expérimental et de la bioinformatique pour les analyses d&#39;ARN-Seq de la photopériode diapause dans le Asian Tiger Mosquito,<em&gt; Aedes albopictus</em

Photoperiodic diapause is an important adaptation that allows individuals to escape harsh seasonal environments via a series of physiological changes, ...

Using Mouse Mammary Tumor Cells to Teach Core Biology Concepts: A Simple Lab Module

Undergraduate biology students are required to learn, understand and apply a variety of cellular and molecular biology concepts and techniques in preparation for biomedical, graduate and professional programs or careers in science. To address this, a simple laboratory module was devised to teach the concepts of cell division, cellular communication and cancer through the application of animal cell culture techniques. Here the mouse mammary tumor (MMT) cell line is used to model for breast cancer. Students learn to grow and characterize these animal cells in culture and test the effects of traditional and non-traditional chemotherapy agents on cell proliferation. Specifically, students determine the optimal cell concentration for plating and growing cells, learn how to prepare and dilute drug solutions, identify the best dosage and treatment time course of the antiproliferative agents, and ascertain the rate of cell death in response to various treatments. The module employs both a standard cell counting technique using a hemocytometer and a novel cell counting method using microscopy software. The experimental procedure lends to open-ended inquiry as students can modify critical steps of the protocol, including testing homeopathic agents and over-the-counter drugs. In short, this lab module requires students to use the scientific process to apply their knowledge of the cell cycle, cellular signaling pathways, cancer and modes of treatment, all while developing an array of laboratory skills including cell culture and analysis of experimental data not routinely taught in the undergraduate classroom.

A feasible laboratory module for biology undergraduates that explores advanced cellular and molecular concepts using animal cell culture is described. Students grow, characterize and manipulate a breast cancer cell model by exposure to chemotherapy agents. Cell viability is assayed through cell counting using both a standard and novel method.

Utilisation de la souris des cellules tumorales mammaires pour enseigner Biologie Concepts de base: un module de laboratoire simple

Undergraduate biology students are required to learn, understand and apply a variety of cellular and molecular biology concepts and techniques in ...

Microperfusion Technique to Investigate Regulation of Microvessel Permeability in Rat Mesentery

Experiments to measure the permeability properties of individually perfused microvessels provide a bridge between investigation of molecular and cellular mechanisms regulating vascular permeability in cultured endothelial cell monolayers and the functional exchange properties of whole microvascular beds. A method to cannulate and perfuse venular microvessels of rat mesentery and measure the hydraulic conductivity of the microvessel wall is described. The main equipment needed includes an intravital microscope with a large modified stage that supports micromanipulators to position three different microtools: (1) a beveled glass micropipette to cannulate and perfuse the microvessel; (2) a glass micro-occluder to transiently block perfusion and enable measurement of transvascular water flow movement at a measured hydrostatic pressure, and (3) a blunt glass rod to stabilize the mesenteric tissue at the site of cannulation. The modified Landis micro-occlusion technique uses red cells suspended in the artificial perfusate as markers of transvascular fluid movement, and also enables repeated measurements of these flows as experimental conditions are changed and hydrostatic and colloid osmotic pressure difference across the microvessels are carefully controlled. Measurements of hydraulic conductivity first using a control perfusate, then after re-cannulation of the same microvessel with the test perfusates enable paired comparisons of the microvessel response under these well-controlled conditions. Attempts to extend the method to microvessels in the mesentery of mice with genetic modifications expected to modify vascular permeability were severely limited because of the absence of long straight and unbranched microvessels in the mouse mesentery, but the recent availability of the rats with similar genetic modifications using the CRISPR/Cas9 technology is expected to open new areas of investigation where the methods described herein can be applied.

The modified Landis technique enables paired measurement of the hydraulic conductivity of individual microvessels in the mesentery of normal and genetically modified rats under control and test conditions using microperfusion techniques. It provides a convenient method to evaluate mechanisms that regulate microvessel permeability and transvascular exchange under physiological conditions.

Microperfusion Technique chargé d&#39;enquêter sur le règlement des microvaisseaux perméabilité au Rat Mesentery

Experiments to measure the permeability properties of individually perfused microvessels provide a bridge between investigation of molecular and cellular ...