We thank Dr. Helio Salgado, Renata Lataro and Mauro de Oliveira, School of Medicine of Ribeir&atilde;o Preto, University of Sao Paulo and Dr. Ben Janssen, Cardiovascular Research Institute Maastricht, Maastricht University, for generous assistance during the set up process.
This work was supported by FONDECYT grant N&deg; 11090114 to S.D.C.

Protocol was approved by the Ethic Committee of Facultad de Medicina Clinica Alemana-Universidad del Desarrollo.
I. Preparing Dobutamine Infusion
<ol>
 <li>Dissolve 10 mg of dobutamine in 20 ml of sterile distillated water, in order to obtain a stock solution of 500 &mu;g/ml dobutamine. Aliquot and store at -20 &deg;C. This solution can be used at least for 3 months. </li>
 <li>Thaw an aliquot of dobutamine stock solution at room temperature. </li>
 <li>Dilute dobutamine stock solution...

<ol>
	<li>Hart, C. Y., Burnett, J. C., Redfield, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+avertin+versus+xylazine-ketamine+anesthesia+on+cardiac+function+in+normal+mice.">Effects of avertin versus xylazine-ketamine anesthesia on cardiac function in normal mice.</a> Am. J. Physiol. Heart Circ. Physiol. 281, H1938-H1945 (2001).</li><li>Janssen, B. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+anesthetics+on+systemic+hemodynamics+in+mice.">Effects of anesthetics on systemic hemodynamics in mice.</a> Am. J. Physiol. Heart Circ. Physiol. 287, H1618-H1624 (2004).</li><li>Lorenz, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+practical+guide+to+evaluating+cardiovascular,+renal,+and+pulmonary+function+in+mice.">A practical guide to evaluating cardiovascular, renal, and pulmonary function in mice.</a> Am. J. Physiol. Regul. Integr. Comp. Physiol. 282, R1565-R1582 (2002).</li><li>Lorenz, J. N., Robbins, J. <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+intraventricular+pressure+and+cardiac+performance+in+the+intact+closed-chest+anesthetized+mouse.">Measurement of intraventricular pressure and cardiac performance in the intact closed-chest anesthetized mouse.</a> Am. J. Physiol. 272, H1137-H1146 (1997).</li><li>Nemoto, S., DeFreitas, G., Carabello, 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=Cardiac+catheterization+technique+in+a+closed-chest+murine+model.">Cardiac catheterization technique in a closed-chest murine model.</a> Contemp. Top. Lab Anim. Sci. 42, 34-38 (2003).</li><li>Daniels, 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=Impaired+cardiac+functional+reserve+in+type+2+diabetic+db/db+mice+is+associated+with+metabolic,+but+not+structural,+remodelling.">Impaired cardiac functional reserve in type 2 diabetic db/db mice is associated with metabolic, but not structural, remodelling.</a> Acta Physiol. (Oxf). 200, 11-22 (2010).</li><li>De Celle, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+structural+and+functional+consequences+of+cardiac+ischaemia-reperfusion+injury+in+vivo+in+mice.">Long-term structural and functional consequences of cardiac ischaemia-reperfusion injury in vivo in mice.</a> Exp. Physiol. 89, 605-615 (2004).</li><li>Huntgeburth, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transforming+growth+factor+beta+oppositely+regulates+the+hypertrophic+and+contractile+response+to+beta-adrenergic+stimulation+in+the+heart.">Transforming growth factor beta oppositely regulates the hypertrophic and contractile response to beta-adrenergic stimulation in the heart.</a> PLoS One. 6, e26628 (2011).</li><li>Reddy, A. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+function+in+young+and+old+Little+mice.">Cardiac function in young and old Little mice.</a> J. Gerontol. A. Biol. Sci. Med. Sci. 62, 1319-1325 (2007).</li><li>Christoffersen, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+lipid+accumulation+associated+with+diastolic+dysfunction+in+obese+mice.">Cardiac lipid accumulation associated with diastolic dysfunction in obese mice.</a> Endocrinology. 144, 3483-3490 (2003).</li></ol>

No conflicts of interest declared.

Cardiac stress test induced by dobutamine and monitored by cardiac catheterization is laborious. Nonetheless, following the protocol here describe and with a short time of training, it is possible to assess six hemodynamic parameters in a single experiment that last approximately one hour.
The critical steps of the protocol here presented are the cannulations of blood vessels. Regarding the cannulation of carotid artery, the incision performed should be deep enough to break the three tissue la...

<table border="1">
<tbody>
 <tr>
 <td></td>
 <td></td>
 <td></td>
 <td>Reagents</td>
 </tr>
 <tr>
 <td>PE-50/10</td>
 <td>Warner 			Instruments</td>
 <td>64-0752</td>
 <td></td>
 </tr>
 <tr>
 <td>Silk 			thread 6/0 HR17</td>
 <td>Tagum</td>
 <td>SN0713K</td>
 <td></td>
 </tr>
 <tr>
 <td>Xylacin 			20 mg/ml</td>
 <td>Laboratorio 			Centrovet</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Ketamine 			100 mg/ml</td>
 <td>Drag 			Pharma</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Sodium 			chloride 0.9%</td>
 <td>Lab 			Sanderson S.A.</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Dobutamine 			hydrochloride</td>
 <td>Sigma-Aldrich</td>
 <td>D0676</td>
 <td></td>
 </tr>
 <tr>
 <td>Syringe 			U-100 Insulin 29G x &frac12;"</td>
 <td>Terumo 			Medical Co.</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Forceps Dissecting Micro 11.5 cm 			Style 7</td>
 <td>Lawton 			Medizintechnik</td>
 <td>09-0959</td>
 <td></td>
 </tr>
 <tr>
 <td>Graefe Forceps Cvd 0.7mm 7cm</td>
 <td>Lawton 			Medizintechnik</td>
 <td>62-0263</td>
 <td></td>
 </tr>
 <tr>
 <td>Clamps Dieffenbach bulldog Cl Str 38 			mm </td>
 <td>Lawton 			Medizintechnik</td>
 <td>60-010</td>
 <td></td>
 </tr>
 <tr>
 <td>Vannas 			Scissors 8 cm Str Fh</td>
 <td>Lawton 			Medizintechnik</td>
 <td>63-1400</td>
 <td></td>
 </tr>
 <tr>
 <td></td>
 <td></td>
 <td></td>
 <td>Equipment</td>
 </tr>
 <tr>
 <td>SPR-671 			MiKro-Tip Pressure catheter</td>
 <td>Millar 			instruments</td>
 <td>840-6719</td>
 <td></td>
 </tr>
 <tr>
 <td>PCU-2000 Pressure 			Control Unit</td>
 <td>Millar 			instruments</td>
 <td>880-0129</td>
 <td></td>
 </tr>
 <tr>
 <td>PowerLab 			4/30</td>
 <td>ADinstruments 			Pty Ltd.</td>
 <td>ML866</td>
 <td></td>
 </tr>
 <tr>
 <td>LabChartPro 			7 </td>
 <td>ADinstruments 			Pty Ltd.</td>
 <td>MLU260/7</td>
 <td></td>
 </tr>
 <tr>
 <td>Legato200 Infusion 			Pump</td>
 <td>KdScientific</td>
 <td>KD-KDS210P</td>
 <td></td>
 </tr>
 <tr>
 <td>TCAT-2LV Temperature 			controller and isothermal heating plate</td>
 <td>PhysiTemp 			instruments Inc.</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Medical 			Oxygen supply</td>
 <td>Indura </td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Rectal 			probe </td>
 <td>ADinstruments 			Pty Ltd.</td>
 <td>MLT1404</td>
 <td></td>
 </tr>
 <tr>
 <td>Trinocular 			microscope, axial illumination</td>
 <td>LW 			Scientific</td>
 <td>Z2B-TRI-ETNE, 			ILP-1502-LTS1, ILP-1502-DGGF</td>
 <td></td>
 </tr>
 </tbody>
</table>

cardiac stress test induced by dobutamine and monitored by cardiac catheterization in mice

Dobutamine is a &beta;-adrenergic agonist with an affinity higher for receptor expressed in the heart (&beta;1) than for receptors expressed in the arteries (&beta;2). When systemically administered, it increases cardiac demand. Thus, dobutamine unmasks abnormal rhythm or ischemic areas potentially at risk of infarction. 
Monitoring of heart function during a cardiac stress test can be performed by either ecocardiography or cardiac catheterization. The latter is an invasive but more accurate and informative technique that the former.
Cardiac stress test induced by dobutamine and monitored by cardiac catheterization accomplished as described here allows, in a single experiment, the measurement of the following hemodynamic parameters: heart rate (HR), systolic pressure, diastolic pressure, end-diastolic pressure, maximal positive pressure development (dP/dtmax) and maximal negative pressure development (dP/dtmin), at baseline conditions and under increasing doses of dobutamine.
As expected, in normal mice we observed a dobutamine dose-related increase in HR, dP/dtmax and dP/dtmin. Moreover, at the highest dose tested (12 ng/g/min) the cardiac decompensation of high fat diet-induced obese mice was unmasked.

The arterial pressure signal is defined by systolic and diastolic pressure. When the pressure sensor is inside the left ventricle, its pressure (LVP) waveform is characterized by a drop to zero of the diastolic pressure and the appearance of the left atrial contraction before ventricle contraction (Figure 1). At baseline condition, ketamine-xylazine anesthetized normal mice had HR of 280 &plusmn; 24, Pmax of 107 &plusmn; 8, Pmin of 5 &plusmn; 1, EDP of 14 &plusmn; 2, dP/dtmax</...

Watch this Scientific Journal Video about Cardiac Stress Test Induced by Dobutamine and Monitored by Cardiac Catheterization in Mice at JoVE.com

Cardiac Stress Test Induced by Dobutamine and Monitored by Cardiac Catheterization in Mice

We describe the protocol to perform a cardiac stress test induced by dobutamine and monitored by cardiac catheterization in normal mice. Also we show its application to unmask subclinical cardiac disease in high fat diet-induced obese mice.

Dobutamine is a &beta;-adrenergic agonist with an affinity higher for receptor expressed in the heart (&beta;1) than for receptors expressed in the ...

cardiac-stress-test-induced-dobutamine-monitored-cardiac

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17.9K Views.  Clínica Alemana Universidad del Desarrollo. We describe the protocol to perform a cardiac stress test induced by dobutamine and monitored by cardiac catheterization in normal mice. Also we show its application to unmask subclinical cardiac disease in high fat diet-induced obese mice.