The work was supported by grants from NIH/NINDS (NS054883), Craig H. Neilsen Foundation (280072), and the Veterans Administration and Canadian Spinal Research Organization. We thank the Rat Resource and Research Center, University of Missouri, Columbia, Missouri, for providing GFP rats.

All animal protocols were approved by the Institutional Animal Care and Use Committee (IACUC). NIH guidelines for laboratory animal care and safety are strictly followed. Animals with surgical procedures were adequately treated for minimizing pain and discomfort.
1. Spinal Cord Curgery and Cell Grafting
<ol>
	<li>Autoclave surgical instruments prior to all surgeries. Use Hot Bead Sterilizer (Fine Science Tools) to remove pathogens and microbial contaminants from instruments between procedure...

<ol>
	<li>Krassioukov, A. V., Furlan, J. C., Fehlings, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autonomic+dysreflexia+in+acute+spinal+cord+injury:+an+under-recognized+clinical+entity.">Autonomic dysreflexia in acute spinal cord injury: an under-recognized clinical entity.</a> J Neurotrauma. 20, 707-716 (2003).</li><li>Lindan, R., Joiner, E., Freehafer, A. A., Hazel, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Incidence+and+clinical+features+of+autonomic+dysreflexia+in+patients+with+spinal+cord+injury.">Incidence and clinical features of autonomic dysreflexia in patients with spinal cord injury.</a> Paraplegia. 18, 285-292 (1980).</li><li>Inskip, J. A., Ramer, L. M., Ramer, M. S., Krassioukov, A. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autonomic+assessment+of+animals+with+spinal+cord+injury:+tools,+techniques+and+translation.">Autonomic assessment of animals with spinal cord injury: tools, techniques and translation.</a> Spinal Cord. 47, 2-35 (2009).</li><li>Mayorov, D. N., Adams, M. A., Krassioukov, A. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Telemetric+blood+pressure+monitoring+in+conscious+rats+before+and+after+compression+injury+of+spinal+cord.">Telemetric blood pressure monitoring in conscious rats before and after compression injury of spinal cord.</a> J Neurotrauma. 18, 727-736 (2001).</li><li>Hou, S., Tom, V. J., Graham, L., Lu, P., Blesch, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Partial+restoration+of+cardiovascular+function+by+embryonic+neural+stem+cell+grafts+after+complete+spinal+cord+transection.">Partial restoration of cardiovascular function by embryonic neural stem cell grafts after complete spinal cord transection.</a> J Neurosci. 33, 17138-17149 (2013).</li><li>Lu, P., 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-distance+growth+and+connectivity+of+neural+stem+cells+after+severe+spinal+cord+injury.">Long-distance growth and connectivity of neural stem cells after severe spinal cord injury.</a> Cell. 150, 1264-1273 (2012).</li><li>Akhavan, M., Hoang, T. X., Havton, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+detection+of+fluorogold-labeled+neurons+in+long-term+studies.">Improved detection of fluorogold-labeled neurons in long-term studies.</a> J Neurosci Methods. 152, 156-162 (2006).</li><li>Maiorov, D. N., Fehlings, M. G., Krassioukov, A. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relationship+between+severity+of+spinal+cord+injury+and+abnormalities+in+neurogenic+cardiovascular+control+in+conscious+rats.">Relationship between severity of spinal cord injury and abnormalities in neurogenic cardiovascular control in conscious rats.</a> J Neurotrauma. 15, 365-374 (1998).</li><li>Laird, A. S., Carrive, P., Waite, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiovascular+and+temperature+changes+in+spinal+cord+injured+rats+at+rest+and+during+autonomic+dysreflexia.">Cardiovascular and temperature changes in spinal cord injured rats at rest and during autonomic dysreflexia.</a> J Physiol. 577, 539-548 (2006).</li><li>Phillips, A. A., Krassioukov, A. V., Ainslie, P. N., Warburton, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Baroreflex+function+after+spinal+cord+injury.">Baroreflex function after spinal cord injury.</a> J Neurotrauma. 29, 2431-2445 (2012).</li><li>Osborn, J. W., Taylor, R. F., Schramm, L. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determinants+of+arterial+pressure+after+chronic+spinal+transection+in+rats.">Determinants of arterial pressure after chronic spinal transection in rats.</a> Am J Physiol. 256, 666-673 (1989).</li><li>Rabchevsky, A. 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=Effects+of+gabapentin+on+muscle+spasticity+and+both+induced+as+well+as+spontaneous+autonomic+dysreflexia+after+complete+spinal+cord+injury.">Effects of gabapentin on muscle spasticity and both induced as well as spontaneous autonomic dysreflexia after complete spinal cord injury.</a> Front Physiol. 3, 329 (2012).</li><li>Hou, S., Lu, P., Blesch, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+supraspinal+vasomotor+pathways+and+autonomic+dysreflexia+after+spinal+cord+injury+in+F344+rats.">Characterization of supraspinal vasomotor pathways and autonomic dysreflexia after spinal cord injury in F344 rats.</a> Auton Neurosci. 176, 54-63 (2013).</li></ol>

Traditionally, a fluid filled cannula is inserted into the artery and connected to a pressure transducer to record cardiovascular parameters as a terminal snapshot in each animal11. To continuously monitor cardiovascular performance for a long time, radio-telemetric systems are employed in many laboratories. This more refined tool can record blood pressure in conscious, freely moving animals. Compared to fluid filled catheters, telemetry is considered a more advanced technique to accurately evaluate cardiovasc...

Cardiovascular dysfunction occurs after spinal cord injury (SCI) at high levels. It is manifested in disordered blood pressure and heart rate at rest, orthostatic hypotension, exercise-induced hypotension, and autonomic dysreflexia characterized by episodes of hypertension and baroreflex-mediated bradycardia in response to sensory stimuli below the injury level1,2. These symptoms interfere with the daily living of spinal cord injured patients. Thus, it is important to establish effective tools for the investigation of cardiovascular changes in animals with SCI and experimental treatments.
To investigate cardiovascular function in animals, several techniques have been used to monitor blood pressure and heart rate. Central cardiovascular parameters can be recorded by cannula insertion and telemetry, whereas noninvasive tail-cuffs can be employed to measure peripheral blood pressure3. Compared to other methods, telemetry has the main advantage that it allows for continuous recording in freely moving animals and long-term monitoring of cardiovascular function4. In SCI animal models, the changes in peripheral blood pressure after experimental stimulation may not be large enough to be detected. Accordingly, suitable cardiac monitoring technique should be selected for animals with SCI.
In the present study, a radio-telemetric system was introduced to monitor cardiovascular function in adult rats after complete spinal cord transection. Rats received grafts of syngeneic rat embryonic day 14 (E14) brainstem-derived neural stem cells (BS-NSCs) in the lesion site. Rats with injury and no transplant and na&#239;ve, uninjured rats served as controls. The procedure of telemetry includes transmitter sterilization and implantation (Figure 1), recording of basal cardiovascular parameter, colorectal distension-induced responses, and transmitter cleaning and storage.

<table border="0" cellpadding="0" cellspacing="0" width="580">
	<tbody>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:315px;">Table of Specific Materials/Equipment:</td>
			<td style="width:103px;"></td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="20">
			<td height="41" rowspan="2" style="height:41px;width:120px;">Reagents</td>
			<td rowspan="2" style="width:195px;">Company</td>
			<td rowspan="2" style="width:103px;">Catalogue</td>
			<td rowspan="2" style="width:164px;">Comment</td>
		</tr>
		<tr height="21">
		</tr>
		<tr height="62">
			<td height="83" rowspan="2" style="height:83px;width:120px;">Fibrinogen (rat)</td>
			<td rowspan="2" style="width:195px;">Sigma</td>
			<td rowspan="2" style="width:103px;">F6755-25MG</td>
			<td rowspan="2" style="width:164px;">2 hr at 37oC to dissovle</td>
		</tr>
		<tr height="21">
		</tr>
		<tr height="59">
			<td height="80" rowspan="2" style="height:80px;width:120px;">Thrombin (rat)</td>
			<td rowspan="2" style="width:195px;">Sigma</td>
			<td rowspan="2" style="width:103px;">T5772-100UN</td>
			<td rowspan="2" style="width:164px;">Dissovle in 10 mM CaCl2</td>
		</tr>
		<tr height="21">
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:120px;">1% Terg-A-Zyme</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:103px;">Z273287</td>
			<td style="width:164px;">Enzymatic solution for telemeter cleaning</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:120px;">Fluorogold</td>
			<td style="width:195px;">Fluorochrome</td>
			<td style="width:103px;"></td>
			<td style="width:164px;">Dissovle in distilled water and avoid light</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:120px;">Telemeter&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; (PA-C40)</td>
			<td style="width:195px;">Data Sciences International</td>
			<td style="width:103px;"></td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:120px;">Telementric recording and analysis system</td>
			<td style="width:195px;">Data Sciences International</td>
			<td style="width:103px;"></td>
			<td style="width:164px;">Signal stimulator, Data Exchange Matrix, receivers, Ambient pressure reference monitor</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:120px;">Balloon-tipped catheter</td>
			<td style="width:195px;">Edward Lifesciences</td>
			<td style="width:103px;">111F7-P</td>
			<td style="width:164px;">For colorectal distension</td>
		</tr>
	</tbody>
</table>

a radio-telemetric system to monitor cardiovascular function in rats with spinal cord transection and embryonic neural stem cell grafts

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter connected to a radio transmitter into the femoral artery of rats that underwent a T4 spinal cord transection with or without grafting of embryonic brainstem-derived neural stem cells expressing green fluorescent protein. Compared to other methods such as cannula insertion or tail-cuff, telemetry is advantageous to continuously monitor blood pressure and heart rate in freely moving animals. It is also capable of long term multiple data acquisitions. In spinal cord injured rats, basal cardiovascular data under unrestrained condition and autonomic dysreflexia in response to colorectal distension were successfully recorded. In addition, cardiovascular parameters before and after SCI can be compared in the same rat if a transmitter is implanted before a spinal cord transection. One limitation of the described telemetry procedure is that implantation in the femoral artery may influence the blood supply to the ipsilateral hindlimb.

Using the above described telemetry technique, we successfully recorded cardiovascular parameters in spinal cord injured animals. In animals with SCI alone, MAP was significantly reduced whereas HR increased compared to na&#239;ve animals, consistent with previous reports9. In animals with BS-NSC grafting, MAP and HR approached levels measured in na&#239;ve animals (Figure 2). During colorectal distension, a rat was regarded as dysreflexic if the noxious stimulation produced a rise in MAP and ...

Watch this Scientific Journal Video about A Radio-telemetric System to Monitor Cardiovascular Function in Rats with Spinal Cord Transection and Embryonic Neural Stem Cell Grafts at JoVE.com

A Radio-telemetric System to Monitor Cardiovascular Function in Rats with Spinal Cord Transection and Embryonic Neural Stem Cell Grafts

We present a protocol for using a radio-telemetric system to record cardiovascular parameters in T4 spinal cord transected rats eight weeks after embryonic brainstem neural stem cell grafting into the lesion site. Telemetry is an advanced technique to accurately evaluate cardiovascular function in conscious freely moving spinal cord injured rats.

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter ...

a-radio-telemetric-system-to-monitor-cardiovascular-function-rats

Research

JoVE Journal

Medicine

10.4K Views.  Drexel University College of Medicine.  Vi presentiamo un protocollo per l'utilizzo di un sistema radio-telemetrico per registrare i parametri cardiovascolari in T4 midollo spinale ratti transected otto settimane successive tronco cerebrale embrionale delle cellule staminali neurali innesto nel sito della lesione. Telemetria è una tecnica avanzata per valutare con precisione la funzione cardiovascolare in coscienti liberi di muoversi midollo spinale topi feriti. 