We would like to acknowledge Drs. Robert Gereau, Henry Lai, and Lara Crock for their helpful assistance in setting up this system. We would also like to acknowledge funding sources for this work (BJK &#8211; International Association for the Study of Pain Early Career Research Grant by the Scan&#124;Design Foundation by INGER &#38; JENS BRUUN and the Duquesne University Hunkele Dreaded Disease Fund).

The following protocol has been approved by the Institutional Animal Care and Use Committee at Duquesne University and is consistent with guidelines from the National Institutes of Health.
1. Surgical Implantation of Wire Electrodes and Urinary Bladder Catheter Using Sterile Techniques&#160;(total time 5-10 min)
<ol>
	<li>The following items should be prepared prior to starting surgery:
	<ol>
		<li>Actively monitor and adjust body temperature to 37.5&#177;0.5 &#176;C using temperature monito...

<ol>
	<li>Merskey, H., Bogduk, 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> Classification of Chronic Pain. , (1994).</li><li>Gureje, O., Korff, M. V., Simon, G. E., Gater, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peristent+pain+and+well-being.+A+World+Health+Organization+study+in+primary+care.">Peristent pain and well-being. A World Health Organization study in primary care.</a> J. Am. Med. Assoc. 280, 147-151 (1998).</li><li>Gaskin, D. J., Richard, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+economic+costs+of+pain+in+the+United+States.">The economic costs of pain in the United States.</a> J. Pain. 13, 715-754 (2012).</li><li>Berry, S. 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=Prevalence+of+Symptoms+of+Bladder+Pain+Syndrome/Interstitial+Cystitis+Among+Adult+Females+in+the+United+States.">Prevalence of Symptoms of Bladder Pain Syndrome/Interstitial Cystitis Among Adult Females in the United States.</a> J. Urol. 186, 540-544 (2011).</li><li>Tunitsky, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bladder+Pain+Syndrome/Interstitial+Cystitis+in+twin+sisters.">Bladder Pain Syndrome/Interstitial Cystitis in twin sisters.</a> J. Urol. 187, 148-152 (2012).</li><li>Tettamanti, 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=Influence+of+smoking,+coffee,+and+tea+consumption+on+Bladder+Pain+Syndrome+in+female+twins.">Influence of smoking, coffee, and tea consumption on Bladder Pain Syndrome in female twins.</a> Urology. 77, 1313-1317 (2011).</li><li>Warren, J. W., et al., Longo, D. L., 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=.">.</a> Harrison's Principles of Internal Medicine. , (2012).</li><li>Baldoni, F., Ercolani, M., Baldaro, B., Trombini, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stressful+events+and+psychological+symptoms+in+patients+with+functional+urinary+disorders.">Stressful events and psychological symptoms in patients with functional urinary disorders.</a> Perceptual Motor Skills. 80, 605-606 (1995).</li><li>Tannenbaum, C., Gray, M., Hoffstetter, S., Cardozo, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comorbidities+associated+with+bladder+dysfunction.">Comorbidities associated with bladder dysfunction.</a> Int. J. Clin. Practice. 67, 105-113 (2013).</li><li>Ness, T. J., Elhefni, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reliable+visceromotor+responses+are+evoked+by+noxious+bladder+distention+in+mice.">Reliable visceromotor responses are evoked by noxious bladder distention in mice.</a> J. Urol. 171, 1704-1708 (2004).</li><li>Ness, T. J., Richter, H. E., Varner, R. E., Fillingim, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+psychophysical+study+of+discomfort+produced+by+repeated+filling+of+the+urinary+bladder.">A psychophysical study of discomfort produced by repeated filling of the urinary bladder.</a> Pain. 76, 61-69 (1998).</li><li>Ness, T. J., Gebhart, G. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visceral+pain:+a+review+of+experimental+studies.">Visceral pain: a review of experimental studies.</a> Pain. 41, 167-234 (1990).</li><li>Crock, L. 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=Central+amygdala+metabotropic+glutamate+receptor+5+in+the+modulation+of+visceral+pain.">Central amygdala metabotropic glutamate receptor 5 in the modulation of visceral pain.</a> J. Neurosci. 32, 14217-14226 (2012).</li><li>Anderson, R. H., Ness, T. J., Gebhart, G. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+distension+control+device+useful+for+quantitative+studies+of+hollow+organ+sensation.">A distension control device useful for quantitative studies of hollow organ sensation.</a> Physiol. Behav. 41, 635-638 (1987).</li><li>Dimitrakov, 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=Pharmacologic+Management+of+Painful+Bladder+Syndrome/Interstitial+Cystitis:+A+Systematic+Review.">Pharmacologic Management of Painful Bladder Syndrome/Interstitial Cystitis: A Systematic Review.</a> Arch. Intern. Med. 167, 1922-1929 (2007).</li><li>Qin, C., Van Meerveld, B. G. r. e. e. n. w. o. o. d. -., Foreman, 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=Spinal+neuronal+responses+to+urinary+bladder+stimulation+in+rats+with+corticosterone+or+aldosterone+onto+the+amygdala.">Spinal neuronal responses to urinary bladder stimulation in rats with corticosterone or aldosterone onto the amygdala.</a> J. Neurophysiol. 90, 2180-2189 (2003).</li><li>Randich, A., Mebane, H., DeBerry, J. J., Ness, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rostral+ventral+medulla+modulation+of+the+visceromotor+reflex+evoked+by+urinary+bladder+distension+in+female+rats.">Rostral ventral medulla modulation of the visceromotor reflex evoked by urinary bladder distension in female rats.</a> J. Pain. 9, 920-926 (2008).</li></ol>

In humans, interstitial cystitis/bladder pain syndrome (IC/BPS) represents a significant clinical problem because patients have debilitating pain that is often unresponsive to regular pain treatment15. One of the major challenges in understanding and ultimately treating chronic bladder pain is to understand the normal neural processes that are involved in the response to noxious bladder distention. In order to overcome this challenge, an animal model of bladder pain is necessary. This model should be reproduci...

Chronic pain is officially defined as pain that persists for approximately three months, or for longer than the normal tissue healing time1. This type of pain is one of the main reasons that people are driven to seek medical attention2 and can cost up to $635 billion dollars annually3. Current chronic pain coping strategies are considered archaic; after decades of medical advancements, NSAIDs (nonsteroidal anti-inflammatory drugs) and opioids are still the primary treatments prescribed by physicians. However these treatments target all different types of pain in the same way, providing analgesic effects all over the body as opposed to specifically focusing on the cause of that exact pain incident. In order to better help those suffering from chronic pain, research attention should be shifted towards the etiology and possible pain-specific treatments associated with the most common causes of chronic pain. The goal of this manuscript is to describe a model used to better understand a condition known as Interstitial Cystitis/Painful Bladder Syndrome (IC/BPS).
IC/BPS is a debilitating condition that affects millions of people, primarily women over the age of 40 4. The exact causes of IC/BPS are not known, however prevalence has been linked to genetics5, specific diets, and high stress levels6. Symptoms of IC/BPS include but are not limited to: Increased urgency to urinate, increased frequency of urination, aching, piercing, or burning pain during bladder filling and voiding, and nocturia7. Patients experiencing these conditions have higher stress levels and are more anxious8. This increased stress results in increased pain, which augments the original stress levels. Studies have shown that depression and anxiety levels decrease following treatments that relieve urinary pain, thus effectively breaking this positive-feedback cycle9. One of the challenges in discovering new treatments for IC/BPS has been the paucity of a basic science understanding of bladder pain.
In order to study nervous system contributions to the condition, many animal models have been developed to mimic the pain and symptoms associated with IC/BPS. Traditionally, cystitis has been recreated in animals with the introduction of various chemicals such as mustard oil, acetone, lipopolysaccharide, hydrochloric acid, and cyclophosphamide into the bladder. However no foreign agents are present in the sterile urine of IC/BPS patients, thus questioning the validity of these models. Another murine model of urological pain is urinary bladder distension (UBD)10. In this model, compressed air of a specific pressure is delivered to the bladder of an awake or lightly anesthetized animal over a set period of time. Throughout the procedure, wires in the superior oblique abdominal muscles record electrical activity from the muscle (with an electromyogram (EMG)). This activity is known as the visceromotor response (VMR) and is reliable, reproducible measure of nociception10. Similar hollow organ distention (e.g. bladder, rectum) in healthy human volunteers produces feelings of discomfort and significant increases in reported pain11,12, traits that are often used to diagnose IC/BPS. Thus, in conjunction with electrical, pharmacological, and optogenetic methods of stimulation or inhibition, UBD is a useful and valid model for understanding both the peripheral and central nervous system components of bladder nociception and pain.
Here, we describe the procedure for UBD as is currently used in our laboratory within female members of the common mouse strain, C57Bl/6J. Due to difficulties in the catheterization process of males, this procedure is primarily performed in female mice. This protocol has been adapted from that developed by Ness et al.10 and previously published from our lab13. The following protocol describes four primary components of this model in anesthetized animals: (1) bladder catheter and recording electrode surgery (2) partial anesthesia induction (3) bladder distention and VMR recording, and (4) data analysis of raw VMR/EMG traces. Subtle differences in the UBD-VMR procedure due to choice of organism, anesthesia depth and induction, and body temperature are discussed below.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Infrared heating blanket and monitoring system</td>
			<td>Kent Scientific</td>
			<td>Right-Temp System&#160;</td>
			<td>This system is setup to monitor two separate temperatures.&#160; This should include the animal and the heating blanket.&#160; In addition, the system can automatically adjust the temperature to maintain a set temp.&#160; However, this automatic function produces electrical interference during EMG recording and must be turned off.&#160; Kent can provide a battery pack for the heating pad for use during the riEMG recording part of the experiment.</td>
		</tr>
		<tr>
			<td>Isoflurane vaporizer</td>
			<td>Draeger</td>
			<td>Vapor 19.1</td>
			<td>Any isoflurane vaporizer will work, but it is helpful to have one that has mutliple notches between 0 and 2% isoflurane.</td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>100% Oxygen air tank</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td>For ventilation of animal</td>
		</tr>
		<tr>
			<td>Air breathing grade</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td>For bladder distention</td>
		</tr>
		<tr>
			<td>24GA 0.56inch IV catheter</td>
			<td>BD biosciences&#160;</td>
			<td>381411</td>
			<td>For bladder catheterization</td>
		</tr>
		<tr>
			<td>Surgilube (sterile)</td>
			<td>Savage Laboratories</td>
			<td>0281-0205-02</td>
			<td>Any surgical grade lubricate would work fine.</td>
		</tr>
		<tr>
			<td>Mineral oil (sterile)</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Saline (sterile)</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>AG8W Silver Wire, 2 m, 0.20 mm (.008&#34;) D, L, No Insulation&#160;</td>
			<td>Warner Instruments</td>
			<td>W4 64-1318&#160;</td>
			<td>Any silver wire with these specifications will work.&#160; Wire does not need to be &#34;chlorinated.&#34;</td>
		</tr>
		<tr>
			<td>opthalamic ointment</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Small surgical scissors</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Sharp forceps</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>21 Ga needle</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Grass amplifier P511 with 3-lead input cable</td>
			<td>Grass Instruments</td>
			<td>P511 (F-P5IC3/REV1)</td>
			<td>This is the &#34;amplifier&#34; used in the protocol.&#160; Amplifier with the following settings: Calibrator = 1 mV; Lo freq = 300 Hz; Amplification = 20; Hi freq = 10 kHz; Line filter = in.</td>
		</tr>
		<tr>
			<td>Cambridge Electronic Design (CED) 1401 Plus (or equivalent)</td>
			<td>Cambridge Electronic Design</td>
			<td>1401 Plus</td>
			<td>This is the &#34;digitizer&#34; used in the protocol.&#160; Other digitizer systems from WINDAQ or other companies would work fine; Need inputs for pressure signal, EMG, and stimulus signal.</td>
		</tr>
		<tr>
			<td>CED Spike2 software</td>
			<td>Cambridge Electronic Design</td>
			<td>Spike 2</td>
			<td>This is the the &#34;digitizer software&#34; used in the protocol.&#160; Should be from same manufacturer as digitizer.&#160; Program should be setup with 3 channels for pressure (0-100 mmHg scale), EMG signal (typically -5 to +5 V range), and stimulus marker (0-2 V) range.</td>
		</tr>
		<tr>
			<td>Flow chart from air tank to bladder catheter</td>
			<td>n/a</td>
			<td>n/a</td>
			<td>Sequence of connections from pressurized air tank to animal bladder:&#160; Air tank to 1/4 inch tubing to Gilmont flowmeter to Y connector.&#160; Branch 1 of y connector to to sphygmomanometer.&#160; Branch 2 to a single input on the 4-way gang valve to 4-way valve output to the timed pressure regulator to 3/32 tubing from timed pressure regulator to 2nd Y connector (branch 1 to sphygmomanometer) with branch 2 to 3/32 tubing&#160; to a 3rd Y connector.&#160; Branch 1 of Y connector to a 3rd sphygmomanometer and branch 2 to animal bladder catheter.</td>
		</tr>
		<tr>
			<td>Gilmont Flowmeter&#160;</td>
			<td>Gilmont</td>
			<td>GF8321-1401</td>
			<td>Multiple brands of flowmeters will work.&#160; For bladder distention air, flow meter should be able to handle high pressures (such as this Gilmont meter).&#160; For breathing air, flow rate should be adjustable down to 100 cc/min (typical mouse rate is 500-1000 cc/min).&#160;</td>
		</tr>
		<tr>
			<td>4-way gang valve</td>
			<td>Elite</td>
			<td></td>
			<td>This is a specific piece of equipment.&#160; The Elite gang valve is designed for fish tanks at low air pressures.&#160; In the bladder distention setup, this valve acts as a safety valves in case the pressure spikes.&#160; Too high pressure during initial turning on of the tank will ruin the pressure transducer in the Timed pressure regulator and/or the sphygnometers. In addition, by providing a small amount of leak in the system, this valve makes it easier to adjust the pressure between 10-80 mmHg.&#160;&#160;</td>
		</tr>
		<tr>
			<td>1/4 inch tubing</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>3/32 inch tubing</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>&#34;Y&#34; connectors (1/4 and 3/32 inch)</td>
			<td>Multiple</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Sphygmomanometer</td>
			<td>CVS</td>
			<td></td>
			<td>Any analog sphygmomanometer from a drug store will work for this application.&#160;&#160;</td>
		</tr>
		<tr>
			<td>Timed Pressure Regulator</td>
			<td>Custom</td>
			<td></td>
			<td>This is a custom built machine (Washington University in St. Louis Machine shop) that allows for automated pressure delivery including digitization of air pressure, control of trial length, inter-trial interval automation, control of trial number, and stimulus onset digital signal.&#160; However, the basic components of the system (pressure on and off for a given trial period) could be controlled with a simple on/off in-line switch.&#160;&#160; Such analog control of a trial would necessitate additional analysis parameters (see below section 4).&#160; In addition, one would have to manually assign the pressure based on the analog sphygmomanometer during data analysis.&#160;&#160;</td>
		</tr>
		<tr>
			<td>IGOR Pro</td>
			<td>Wavemetrics</td>
			<td>n/a</td>
			<td>For analysis of EMG signal. Many different types of software can be used for data analysis in these experiments.</td>
		</tr>
	</tbody>
</table>

urinary bladder distention evoked visceromotor responses as a model for bladder pain in mice

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition characterized by increased urgency and frequency of urination, as well as nocturia and general pelvic pain, especially upon bladder filling or voiding. Despite years of research, the cause of IC/BPS remains elusive and treatment strategies are unable to provide complete relief to patients. In order to study nervous system contributions to the condition, many animal models have been developed to mimic the pain and symptoms associated with IC/BPS. One such murine model is urinary bladder distension (UBD). In this model, compressed air of a specific pressure is delivered to the bladder of a lightly anesthetized animal over a set period of time. Throughout the procedure, wires in the superior oblique abdominal muscles record electrical activity from the muscle. This activity is known as the visceromotor response (VMR) and is a reliable and reproducible measure of nociception. Here, we describe the steps necessary to perform this technique in mice including surgical manipulations, physiological recording, and data analysis. With the use of this model, the coordination between primary sensory neurons, spinal cord secondary afferents, and higher central nervous system areas involved in bladder pain can be unraveled. This basic science knowledge can then be clinically translated to treat patients suffering from IC/BPS.

An illustration of the overall UBD-VMR setup can be seen in Figure 1A. Increasing pressure steps induce an increase in the raw VMR (i.e. EMG) (Figure 1B.) The raw VMR, pressure, and stimulus marker signal that should be observed during recording using digitizer software can be seen in Figure 2. The top channel seen in Figure 2 is the EMG trace (in V). The background signal of the EMG trace should be steady and low amplitude (&#60;0.2 V). If back...

Watch this Scientific Journal Video about Urinary Bladder Distention Evoked Visceromotor Responses as a Model for Bladder Pain in Mice at JoVE.com

Urinary Bladder Distention Evoked Visceromotor Responses as a Model for Bladder Pain in Mice

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition characterized in part by pelvic pain. In order to study nervous system contributions to the condition, a physiological model of urinary bladder pain is used in mice and rats.

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition ...

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17.6K visualizações.  Duquesne University.  Aproximadamente 3-8.000.000 de pessoas nos Estados Unidos sofrem de síndrome intersticial dor cistite / vesical (IC / BPS), uma condição debilitante caracterizada em parte pela dor pélvica. A fim de estudar as contribuições do sistema nervoso para a condição, um modelo fisiológico de dor na bexiga urinária é usado em ratinhos e ratos. 