Name: novel approach for simultaneous recording of renal sympathetic nerve activity and blood pressure with intravenous infusion in conscious, unrestrained mice.
Uploaded: 2018-02-14T12:30:00
Description: Watch this Scientific Journal Video about Novel Approach for Simultaneous Recording of Renal Sympathetic Nerve Activity and Blood Pressure with Intravenous Infusion in Conscious, Unrestrained Mice. at

S.M.H. was supported by postdoctoral fellowships from the Canadian Institutes for Health Research (CIHR), Heart &#38; Stroke Foundation of Canada (HSFC) and Alberta Innovates Health Solutions (AiHS); J.E.H. is supported by a grant from the National Heart, Lung and Blood Institute PO1HL-51971.

All of the experimental procedures are in accordance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals and were approved by the Institutional Animal Care and Use Committee of the University of Mississippi Medical Center.
1. Animals and Housing
<ol>
	<li>House mice (24 - 35 g) upon arrival in the institutional laboratory animal facility.</li>
	<li>Offer mice standard rodent chow and tap water ad libitum at all stages of the experimental protocol in a temperature and humidity ...

<ol>
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E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+recording+of+renal+sympathetic+nerve+activity+in+unrestrained,+conscious+mice.">Direct recording of renal sympathetic nerve activity in unrestrained, conscious mice.</a> Hypertension. 60 (3), 856-864 (2012).</li><li>DeBeck, L. D., Petersen, S. R., Jones, K. E., Stickland, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heart+rate+variability+and+muscle+sympathetic+nerve+activity+response+to+acute+stress:+the+effect+of+breathing.">Heart rate variability and muscle sympathetic nerve activity response to acute stress: the effect of breathing.</a> Am J Physiol Regul Integr Comp Physiol. 299 (1), R80-R91 (2010).</li><li>Krowicki, Z. K., Kapusta, D. 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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=Effect+of+dynamic+exercise+on+renal+sympathetic+nerve+activity+in+conscious+rabbits.">Effect of dynamic exercise on renal sympathetic nerve activity in conscious rabbits.</a> J Appl Physiol. 74 (5), 2099-2104 (1985).</li><li>Matsukawa, K., Ninomiya, I. <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+renal+sympathetic+nerve+activity,+heart+rate+and+arterial+blood+pressure+associated+with+eating+in+cats.">Changes in renal sympathetic nerve activity, heart rate and arterial blood pressure associated with eating in cats.</a> J Physiol. 390, 229-242 (1987).</li><li>Stocker, S. D., Muntzel, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recording+sympathetic+nerve+activity+chronically+in+rats:+surgery+techniques,+assessment+of+nerve+activity,+and+quantification.">Recording sympathetic nerve activity chronically in rats: surgery techniques, assessment of nerve activity, and quantification.</a> Am J Physiol Heart Circ Physiol. 305 (10), 6 (2013).</li><li>Burke, S. L., Lambert, E., Head, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+approaches+to+quantifying+sympathetic+nerve+activity.">New approaches to quantifying sympathetic nerve activity.</a> Curr Hypertens Rep. 13 (3), 249-257 (2011).</li><li>Smith, F. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Techniques+for+recording+renal+sympathetic+nerve+activity+in+awake,+freely+moving+animals.">Techniques for recording renal sympathetic nerve activity in awake, freely moving animals.</a> Methods. 30 (2), 122-126 (2003).</li><li>Miki, K., Kosho, A., Hayashida, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Method+for+continuous+measurements+of+renal+sympathetic+nerve+activity+and+cardiovascular+function+during+exercise+in+rats.">Method for continuous measurements of renal sympathetic nerve activity and cardiovascular function during exercise in rats.</a> Exp Physiol. 87 (1), 33-39 (2002).</li><li>Yoshimoto, M., Miki, K. <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+sympathetic+nerve+activity+in+freely+moving+mice.">Measurement of renal sympathetic nerve activity in freely moving mice.</a> J Physiol. 560, (2004).</li><li>Yoshimoto, M., Miki, K., Fink, G. D., King, A., Osborn, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+angiotensin+II+infusion+causes+differential+responses+in+regional+sympathetic+nerve+activity+in+rats.">Chronic angiotensin II infusion causes differential responses in regional sympathetic nerve activity in rats.</a> Hypertension. 55 (3), 644-651 (2010).</li><li>Salman, I. M., Sarma Kandukuri, ., Harrison, D., L, J., Hildreth, C. M., Phillips, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+conscious+telemetry+recordings+demonstrate+increased+renal+sympathetic+nerve+activity+in+rats+with+chronic+kidney+disease.">Direct conscious telemetry recordings demonstrate increased renal sympathetic nerve activity in rats with chronic kidney disease.</a> Front Physiol. 6, 218 (2015).</li><li>Morgan, D. A., Despas, F., Rahmouni, K. <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+leptin+on+sympathetic+nerve+activity+in+conscious+mice.">Effects of leptin on sympathetic nerve activity in conscious mice.</a> Physiol Rep. 3 (9), (2015).</li><li>Alfie, M. E., Sigmon, D. H., Pomposiello, S. I., Carretero, O. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+high+salt+intake+in+mutant+mice+lacking+bradykinin-B2+receptors.">Effect of high salt intake in mutant mice lacking bradykinin-B2 receptors.</a> Hypertension. 29 (1 Pt 2), 483-487 (1997).</li><li>Dietz, J. R., Landon, C. S., Nazian, S. J., Vesely, D. L., Gower, W. R. <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+cardiac+hormones+on+arterial+pressure+and+sodium+excretion+in+NPRA+knockout+mice.">Effects of cardiac hormones on arterial pressure and sodium excretion in NPRA knockout mice.</a> Exp Biol Med (Maywood). 229 (8), 813-818 (2004).</li><li>Zhang, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclosporine+A-induced+hypertension+involves+synapsin+in+renal+sensory+nerve+endings.">Cyclosporine A-induced hypertension involves synapsin in renal sensory nerve endings.</a> Proc Natl Acad Sci U S A. 97 (17), 9765-9770 (2000).</li><li>Szczesny, G., Veihelmann, A., Massberg, S., Nolte, D., Messmer, K. <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+anaesthesia+using+inhalatory+isoflurane+in+different+strains+of+mice-the+haemodynamic+effects.">Long-term anaesthesia using inhalatory isoflurane in different strains of mice-the haemodynamic effects.</a> Lab Anim. 38 (1), 64-69 (2004).</li><li>Tank, 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=Sympathetic+nerve+traffic+and+circulating+norepinephrine+levels+in+RGS2-deficient+mice.">Sympathetic nerve traffic and circulating norepinephrine levels in RGS2-deficient mice.</a> Auton Neurosci. 136 (1-2), 52-57 (2007).</li><li>Schwarte, L. A., Zuurbier, C. J., Ince, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+ventilation+of+mice.">Mechanical ventilation of mice.</a> Basic Res Cardiol. 95 (6), 510-520 (2000).</li><li>Zuurbier, C. J., Emons, V. M., Ince, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hemodynamics+of+anesthetized+ventilated+mouse+models:+aspects+of+anesthetics,+fluid+support,+and+strain.">Hemodynamics of anesthetized ventilated mouse models: aspects of anesthetics, fluid support, and strain.</a> Am J Physiol Heart Circ Physiol. 282 (6), H2099-H2105 (2002).</li><li>Farnham, M. M., O'Connor, E. T., Wilson, R. J., Pilowsky, 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=Surgical+preparation+of+mice+for+recording+cardiorespiratory+parameters+in+vivo.">Surgical preparation of mice for recording cardiorespiratory parameters in vivo.</a> J Neurosci Methods. 248, 41-45 (2015).</li><li>Cuellar, J. M., Antognini, J. F., Carstens, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+in+vivo+method+for+recording+single+unit+activity+in+lumbar+spinal+cord+in+mice+anesthetized+with+a+volatile+anesthetic.">An in vivo method for recording single unit activity in lumbar spinal cord in mice anesthetized with a volatile anesthetic.</a> Brain Res Brain Res Protoc. 13 (2), 126-134 (2004).</li><li>Carruba, M. O., Bondiolotti, G., Picotti, G. B., Catteruccia, N., Da Prada, 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+diethyl+ether,+halothane,+ketamine+and+urethane+on+sympathetic+activity+in+the+rat.">Effects of diethyl ether, halothane, ketamine and urethane on sympathetic activity in the rat.</a> Eur J Pharmacol. 134 (1), 15-24 (1987).</li><li>Wang, G. F., Mao, X. J., Chen, Z. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Urethane+suppresses+renal+sympathetic+nerve+activity+in+Wistar+rats.">Urethane suppresses renal sympathetic nerve activity in Wistar rats.</a> Eur Rev Med Pharmacol Sci. 18 (10), 1454-1457 (2014).</li><li>Xu, 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=Effects+of+induced+hypothermia+on+renal+sympathetic+nerve+activity+and+baroreceptor+reflex+in+urethane-anesthetized+rabbits.">Effects of induced hypothermia on renal sympathetic nerve activity and baroreceptor reflex in urethane-anesthetized rabbits.</a> Crit Care Med. 28 (12), 3854-3860 (2000).</li><li>Shimokawa, A., Kunitake, T., Takasaki, M., Kannan, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+effects+of+anesthetics+on+sympathetic+nerve+activity+and+arterial+baroreceptor+reflex+in+chronically+instrumented+rats.">Differential effects of anesthetics on sympathetic nerve activity and arterial baroreceptor reflex in chronically instrumented rats.</a> J Auton Nerv Syst. 72 (1), 46-54 (1998).</li><li>Janssen, B. J., Smits, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autonomic+control+of+blood+pressure+in+mice:+basic+physiology+and+effects+of+genetic+modification.">Autonomic control of blood pressure in mice: basic physiology and effects of genetic modification.</a> Am J Physiol Regul Integr Comp Physiol. 282 (6), R1545-R1564 (2002).</li><li>Nunn, N., Feetham, C. H., Martin, J., Barrett-Jolley, R., Plagge, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Elevated+blood+pressure,+heart+rate+and+body+temperature+in+mice+lacking+the+XLalphas+protein+of+the+Gnas+locus+is+due+to+increased+sympathetic+tone.">Elevated blood pressure, heart rate and body temperature in mice lacking the XLalphas protein of the Gnas locus is due to increased sympathetic tone.</a> Exp Physiol. 98 (10), 1432-1445 (2013).</li></ol>

Herein we have outlined, demonstrated and validated a novel method for targeted evaluation of RSNA in conscious mice, free to move and rest comfortably in their home cages. Following surgical implantation of an arterial pressure radiotelemeter, an indwelling intravenous infusion catheter and a custom-designed bipolar RSNA electrode, mice recovered from surgery and were left undisturbed for 48 to 72 hours. Mice remained comfortably settled in their home cage at all times (including experimental periods) with unrestricted ...

Interest in using mice in several areas of biomedical research continues to expand with the development of countless genetically engineered models. For the most part, technical advances have kept pace with the increased use of mice in physiology and there is now an impressive selection of miniaturized devices developed specifically for measuring important physiological parameters in mice. Although telemetric devices for direct measurement of autonomic nervous tone in the conscious rat have been available for over a decade, miniaturized devices for assessing nerve activity in conscious mice are currently not available. Investigators typically circumvent this limitation by evaluating the contribution of the autonomic nervous system with indirect methods (i.e. plasma or urine catecholamines, pharmacological autonomic blockade, spectral analysis of patterns of blood pressure/heart rate)1.
While these approaches provide valuable information, the result is a global picture of overall autonomic tone, rather than revealing the discrete contribution of isolated populations of nerves to the phenomenon under investigation. Alternatively, direct recording of activity from specific nerves has been executed in anesthetized mice, which poses a multitude of concerns. It is exceedingly difficult to maintain stable blood pressure within the physiological range in an anesthetized mouse for several hours following surgery. In fact, in these types of experiments, blood pressure is often unreported or presented at extremely low levels (i.e. 60-80 mmHg vs &#62;100mmHg in a conscious mouse)2. The fragility of the cardiovascular system exhibited in an anesthetized mouse preparation often precludes meaningful assessment of autonomic nerve activity, given the codependent relationship between blood pressure and sympathetic tone3,4.
To address this limitation, a new method for direct recording of renal sympathetic nerve activity (RSNA) in conscious, unrestrained mice, undisturbed within their home cages was developed. Both the surgical and experimental approach for successful implementation of this technique is described in detail. This preparation enables the investigator to simultaneously record arterial pressure via radiotelemetry in addition to RSNA, with the added capability to intravenously infuse agents of interest without disturbing the mouse.
Twenty four hours post-surgery, mice behave normally and do not exhibit signs of pain or distress. Experimental recordings may then commence 48 to 72 hours post-surgery while the mouse rests comfortably in its home cage with unrestricted access to food, water and environmental enrichment. Clear RSNA traces are presented and the characteristic responses of this nerve population to normal physical movements of the animal (such as eating and grooming) are demonstrated in addition to pharmacological modulation of systemic blood pressure. The quality and specificity of the RSNA signal is further validated by ganglionic blockade. This manuscript includes the audiovisual complement to an initially published description of this technique5.

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	<tbody>
		<tr>
			<td>Teflon-coated stainless steel multiple stranded wire</td>
			<td>A-M Systems</td>
			<td>793200</td>
			<td>0.001in diameter bare; 0.0055in diameter coated</td>
		</tr>
		<tr>
			<td>#11 Scalpel Blade</td>
			<td>Fisher Scientific</td>
			<td>ALMM9011</td>
			<td></td>
		</tr>
		<tr>
			<td>Soldering Iron and solder</td>
			<td></td>
			<td></td>
			<td>Any make or model suitable</td>
		</tr>
		<tr>
			<td>Male miniature pin connectors</td>
			<td>A-M Systems</td>
			<td>520200</td>
			<td>Brass with gold plating</td>
		</tr>
		<tr>
			<td>Female miniature pin connectors</td>
			<td>A-M Systems</td>
			<td>520100</td>
			<td>Brass with gold plating</td>
		</tr>
		<tr>
			<td>Heat Shrink tubing</td>
			<td>Radio Shack</td>
			<td>Model #: 278-1610 |&#160;Catalog #: 2781610</td>
			<td>1.6 mm diameter</td>
		</tr>
		<tr>
			<td>Polyethylene 90 (PE90) tubing</td>
			<td>VWR</td>
			<td>CA-63018-703</td>
			<td>0.86mm inner diameter; 1.27mm outer diameter</td>
		</tr>
		<tr>
			<td>Dissecting microscope</td>
			<td>Leica Microsystems</td>
			<td>Leica M80</td>
			<td>Any make or model also suitable</td>
		</tr>
		<tr>
			<td>Polyethylene 10 (PE10) tubing</td>
			<td>Braintree Scientific</td>
			<td>PE10&#160;50 FT</td>
			<td>0.28mm inner diameter; 0.61mm outer diameter</td>
		</tr>
		<tr>
			<td>Super Glue Liquid</td>
			<td>Loctite</td>
			<td>n/a</td>
			<td>Liquid Formula; any brand suitable</td>
		</tr>
		<tr>
			<td>Super Glue Gel</td>
			<td>Loctite</td>
			<td>n/a</td>
			<td>Gel Formula; any brand suitable</td>
		</tr>
		<tr>
			<td>Polyethylene tubing</td>
			<td>Scientific Commodities</td>
			<td>BB31695-PE/13</td>
			<td>For pedestal 2.7mm inner diameter; 4.0mm outer diameter</td>
		</tr>
		<tr>
			<td>Hospital Sterilization Services &#38; Ozone Sterilization packets</td>
			<td></td>
			<td></td>
			<td>Contact local hospital sterilization services</td>
		</tr>
		<tr>
			<td>Isoflurane anesthesia</td>
			<td>Abbott</td>
			<td>05260-05</td>
			<td></td>
		</tr>
		<tr>
			<td>Deltaphase isothermal heat pads &#38; surgical table</td>
			<td>Braintree Scientific</td>
			<td>39OP</td>
			<td>Keep heat pads warm in a 37&#176;C water bath; Corresponding surgical table essential</td>
		</tr>
		<tr>
			<td>Glycopyrrolate</td>
			<td>Amdipharm Mercury Company Limited</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane vaporizer system &#38; flow gauge</td>
			<td>Braintree Scientific</td>
			<td>VP I</td>
			<td>Include medical grade oxygen supply</td>
		</tr>
		<tr>
			<td>Tissue scissors</td>
			<td>Fine Science Tools</td>
			<td>14173-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Fine spring scissors</td>
			<td>Fine Science Tools</td>
			<td>15006-09</td>
			<td></td>
		</tr>
		<tr>
			<td>Small cotton-tipped applicators</td>
			<td>Fisher Scientific</td>
			<td>23400100</td>
			<td></td>
		</tr>
		<tr>
			<td>Fine Straight Forceps</td>
			<td>Fine Science Tools</td>
			<td>11254-20</td>
			<td>#5, FST by Dumont Biologie Tip</td>
		</tr>
		<tr>
			<td>Angled Forceps</td>
			<td>Fine Science Tools</td>
			<td>11251-35</td>
			<td>#5/45 FST by Dumont</td>
		</tr>
		<tr>
			<td>Small Absorbent Spears</td>
			<td>Fine Science Tools</td>
			<td>18105-03</td>
			<td></td>
		</tr>
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			<td>Parafilm</td>
			<td>Sigma Aldrich</td>
			<td>BR701605&#160;ALDRICH</td>
			<td></td>
		</tr>
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			<td>Kwik-Sil 2 component Silicone Polymer</td>
			<td>World Precision Instruments (WPI)</td>
			<td>KWIK-SIL</td>
			<td>Purchase extra specialized tips from WPI</td>
		</tr>
		<tr>
			<td>5-0 Polysorb Suture</td>
			<td>Tyco Healthcare</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>6-0 Silk Suture</td>
			<td>Braintree Scientific</td>
			<td>SUT-S&#160;104</td>
			<td>Deknatel brand, spool</td>
		</tr>
		<tr>
			<td>Radiotelemetry Probe</td>
			<td>Data Sciences International (DSI)</td>
			<td>TA11-PAC10</td>
			<td></td>
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			<td>Radiotelemetry Receiver</td>
			<td>Data Sciences International (DSI)</td>
			<td>PhysioTel RPC-1</td>
			<td></td>
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			<td>Ambient Pressure Reference</td>
			<td>Data Sciences International (DSI)</td>
			<td>Apr-01</td>
			<td></td>
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			<td>Pressure Output Adapter</td>
			<td>Data Sciences International (DSI)</td>
			<td>R11CPA</td>
			<td></td>
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		<tr>
			<td>Rena Pulse Tubing</td>
			<td>Braintree Scientific</td>
			<td>RPT-040</td>
			<td></td>
		</tr>
		<tr>
			<td>Infusion Swivel</td>
			<td>Instech Solomon</td>
			<td>375/D/22</td>
			<td></td>
		</tr>
		<tr>
			<td>Swivel Support Arm &#38; Mount</td>
			<td>Instech Solomon</td>
			<td>SMCLA</td>
			<td></td>
		</tr>
		<tr>
			<td>Polysulfone button&#160;</td>
			<td>Instech Solomon</td>
			<td>LW62S/6</td>
			<td></td>
		</tr>
		<tr>
			<td>Stainless steel spring</td>
			<td>Instech Solomon</td>
			<td>PS62</td>
			<td></td>
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		<tr>
			<td>Vetbond surgical adhesive</td>
			<td>3M</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Triple Antibiotic Ointment</td>
			<td>Fougera</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>PowerLab 8 Channel Data Acquisition System &#38; Software</td>
			<td>ADInstruments</td>
			<td>PowerLab 8/35</td>
			<td></td>
		</tr>
		<tr>
			<td>PVC Insulated Cable</td>
			<td>Belden</td>
			<td>PVC Audio Connection Cable 32 AWG</td>
			<td></td>
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		<tr>
			<td>Preamplification Headstage</td>
			<td>Dagan Corporation</td>
			<td>Model 4002</td>
			<td></td>
		</tr>
		<tr>
			<td>Differential Amplifier</td>
			<td>Dagan Corporation</td>
			<td>EX4-400</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Nitroprusside</td>
			<td>Sigma Aldrich</td>
			<td>71778-25G</td>
			<td></td>
		</tr>
		<tr>
			<td>Phenylephrine</td>
			<td>Sigma Aldrich</td>
			<td>P6126-5G</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile Physiological Saline 0.9% NaCl</td>
			<td>Beckton Dickinson</td>
			<td></td>
			<td>Contact local hospital supplier</td>
		</tr>
		<tr>
			<td>hexamethonium</td>
			<td>Sigma Aldrich</td>
			<td>H0879-5G</td>
			<td></td>
		</tr>
		<tr>
			<td>Stainless Steel top anti vibration table</td>
			<td>n/a</td>
			<td>n/a</td>
			<td>Custom designed in-house; Solid steel plate on a benchtop is also suitable</td>
		</tr>
		<tr>
			<td>Faraday cage</td>
			<td>n/a</td>
			<td>n/a</td>
			<td>Custom designed and constructed in-house</td>
		</tr>
		<tr>
			<td>Small animal hair trimmer</td>
			<td>n/a</td>
			<td>n/a</td>
			<td>Drugstore, men&#39;s beard trimmer suitable</td>
		</tr>
		<tr>
			<td>Dipilatory Cream</td>
			<td>n/a</td>
			<td>n/a</td>
			<td>Veet brand, sensitive skin formula</td>
		</tr>
		<tr>
			<td>10% Povidone Iodine</td>
			<td>Purdue Products</td>
			<td>Betadiene</td>
			<td></td>
		</tr>
		<tr>
			<td>70% Ethanol</td>
			<td>n/a</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Steel microretractors</td>
			<td>n/a</td>
			<td>n/a</td>
			<td>Made in-house. Bend a steel paper clip &#38; loop 4-0 silk to form a retractor</td>
		</tr>
		<tr>
			<td>Hemostats</td>
			<td>Fine Science Tools</td>
			<td>13011-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Heat Gun</td>
			<td>Fisher Scientific</td>
			<td>09-201-27</td>
			<td></td>
		</tr>
	</tbody>
</table>

novel approach for simultaneous recording of renal sympathetic nerve activity and blood pressure with intravenous infusion in conscious, unrestrained mice.

Renal sympathetic nerves contribute significantly to both physiological and pathophysiological phenomena. Evaluating renal sympathetic nerve activity (RSNA) is of great interest in many areas of research such as chronic kidney disease, hypertension, heart failure, diabetes and obesity. Unequivocal assessment of the role of the sympathetic nervous system is thus imperative for proper interpretation of experimental results and understanding of disease processes. RSNA has been traditionally measured in anesthetized rodents, including mice. However, mice usually exhibit very low systemic blood pressure and hemodynamic instability for several hours during anesthesia and surgery. Meaningful interpretation of RSNA is confounded by this non-physiological state, given the intimate relationship between sympathetic nervous tone and cardiovascular status. To address this limitation of traditional approaches, we developed a new method for measuring RSNA in conscious, freely-moving mice. Mice were chronically instrumented with radio-telemeters for continuous monitoring of blood pressure as well as a jugular venous infusion catheter and custom-designed bipolar electrode for direct recording of RSNA. Following a 48-72 hour recovery period, survival rate was 100% and all mice behaved normally. At this time-point, RSNA was successfully recorded in 80% of mice, with viable signals acquired up to 4 and 5 days post-surgery in 70% and 50% of mice, respectively. Physiological blood pressures were recorded in all mice (116&plusmn;2 mmHg; n=10). Recorded RSNA increased with eating and grooming, as well-established in the literature. Furthermore, RSNA was validated by ganglionic blockade and modulation of blood pressure with pharmacological agents. Herein, an effective and manageable method for clear recording of RSNA in conscious, freely-moving mice is described.

Following the described protocol, survival rate was 100% - all mice instrumented in this study survived and recovered well following the surgical procedure. Within 24 hours of surgical preparation, all mice behaved normally, exhibiting typical eating, grooming and exploratory behaviors. No animals showed any sign of pain or distress at this time. 48 hours following surgery, a verifiable and clear RSNA signal was recorded in 10 out of the 12 mice. This signal was maintained in these mice 7...

Watch this Scientific Journal Video about Novel Approach for Simultaneous Recording of Renal Sympathetic Nerve Activity and Blood Pressure with Intravenous Infusion in Conscious, Unrestrained Mice. at

Novel Approach for Simultaneous Recording of Renal Sympathetic Nerve Activity and Blood Pressure with Intravenous Infusion in Conscious, Unrestrained Mice.

Anesthetized mice exhibit non-physiological systemic blood pressure, which precludes meaningful assessment of autonomic tone given the intimate relationship between blood pressure and the autonomic nervous system. Thus, a novel method to simultaneously record renal sympathetic nerve activity and blood pressure with intravenous infusion in conscious mice is outlined.

Renal sympathetic nerves contribute significantly to both physiological and pathophysiological phenomena. Evaluating renal sympathetic nerve activity ...

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JoVE Journal

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