Name: Intracavernosal Pressure Recording to Evaluate Erectile Function in Rodents (Video) | JoVE Journal
Uploaded: 2018-06-06T12:30:00.000+00:00
Duration: 8 min 3 s
Description: Learn intracavernosal pressure recording to evaluate erectile function in rats using catheterization and cavernous nerve stimulation. This method enables precise assessment of erectile response for urology research.

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5 minutes

This work was supported by the Fundamental Research Funds for the Central Universities (020814380018, 020814380077), The China Scholarship Council (CSC, No. 201606195024), Natural Science Foundation of Jiangsu Province (BK20160138), and Key Project supported by Science and Technology Development Foundation, Nanjing Medical University (2014NJMUZD053).

Three-month-old and 18-month-old Sprague-Dawley rats were used in the present study. All animals were handled in accordance with the NIH Guidelines for the Care and Use of Laboratory Animals. Procedures involving animal subjects were approved by the local Institutional Animal Care and Ethics Committee, with an effort to minimize animal suffering. The protocols were approved by the Institutional Animal Care and Use Committee (IACUC) at Nanjing Tech University (Nanjing, China).
The rats were divided into two groups according to their age and preliminary performance in the APO-induced erectile function test prior to ICP recording: the young normal group (YN group) and aged erectile dysfunction group (AE group)10.
1. Preparation Before Surgery
<ol>
	<li>Manually make a pair of bipolar electrodes for the ICP recording (Figure 1). Slightly bend the ends of electrodes, and adjust the distance between two electrodes to 1-2 mm wide, as shown in Figure 1A.</li>
	<li>Connect the electrodes to the stimulator using two crocodile clamps (Figure 1A,B).</li>
	<li>Assemble the catheter system: First, connect a hypodermic 23G needle to a 3-way stopcock with tubing, then connect the stopcock to the pressure transducer. Next, attach a 10-mL syringe to the third end of stopcock to provide heparin saline.</li>
	<li>Carefully check for leakage after filling the whole system with heparin saline (200 U/mL). Then turn the 3-way stopcock to close the syringe channel or the pressure transducer channel (Figure 1C).</li>
	<li>Lift the needle 20 cm up the level of the wooden pad. Then calibrate the pressure recording system to 20 cm H2O. After that, move the height of the needle to verify the accuracy of the recording system. Repeat the calibration until the accuracy was confirmed.</li>
	<li>Transfer the rats from the animal facility to the surgery room, and allow them to become accustomed to the surgery room for at least 30 min.</li>
	<li>The autoclaved instruments are sprayed with 70% ethanol just before surgery</li>
</ol>
2. Surgery Procedure
<ol>
	<li>Anesthetize the rat with an intraperitoneal injection of sodium pentobarbital at a dose of 45 mg/kg body weight, and wait for 5-10 min. Pinch the toes to confirm a proper anesthetization.</li>
	<li>Shave the fur of the abdomen and neck with an electric shaver, and place the rat on its back on a heating pad.</li>
	<li>Wipe the surgery area with 10% povidone-iodine solution soaked cotton balls followed by 70% ethanol soaked cotton balls. Also, apply ophthalmic ointment to prevent the eyes from drying out.</li>
	<li>Catheterize the left carotid artery.
	<ol>
		<li>Grasp the skin of the neck with forceps and make a horizontal incision in the middle of the neck. Incise the muscles, carefully expose the left carotid artery, and isolate a 5-mm section of the vessel.</li>
		<li>Carefully separate the carotid artery from the vagus nerve using forceps, draw a silk suture under the carotid artery, and put a loose tie on the caudal end of the vessel, then make another tight knot on the cranial end of the vessel.</li>
		<li>Caudally clamp the vessel with a bulldog clamp above the suture to stop the blood flow.</li>
		<li>Carefully make an incision on the vessel with microsurgical scissors, and insert the arterial catheter towards the heart with the assistance of the micro-dissecting hook and forceps.</li>
		<li>Fasten the loose caudal ligature around the catheter to secure it. Remove the bulldog clamp to recover the blood flow.</li>
	</ol>
	</li>
	<li>Isolate the CN and Place the Electrode
	<ol>
		<li>Lift the skin and muscle of the abdomen with a pair of forceps. With the dissecting scissors, cut through the lower abdomen to the penis to make a midline incision.</li>
		<li>Gently push the intestine with swab into the upper part of the abdominal cavity.</li>
		<li>Grasp the bladder with a pair of forceps and pull out the bladder from the abdominal cavity. Expose the ventral lobes of the prostate, which is located on the ventral portion of the urethra.</li>
		<li>Pull out the ventral lobes of the prostate, seminal vesicle, and vas deferens to expose the dorsal lobe of the prostate. Find the point of adhesion of the vas deferens and prostate.</li>
		<li>Separate the space between the prostate and vas deferens. Carefully expose the fibrous capsule, which is located posterior to the junction point of the prostate and vas deferens. Then find the major pelvic ganglion (Figure 2). 
		NOTE: The major pelvic ganglion and cavernous nerves can be seen at the surface of the prostate.</li>
		<li>Carefully dry CN area with a sterile swab.&#160;Carefully isolate and hook the right cavernous nerve with the bipolar electrodes.</li>
	</ol>
	</li>
	<li>Catheterize the Left Crura
	<ol>
		<li>Cut a small incision in the skin of the penis with dissecting scissors, and then carefully denude the skin of the penis shaft.</li>
		<li>Dissect the striated penile musculature. Find the upper branch of pubis bone.</li>
		<li>Expose the bulbospongiosus muscle, which covers the spongious bulb.</li>
		<li>Divide the bulbospongiosus muscle from the ischiocavernosus muscle by using curved forceps.</li>
		<li>Carefully isolate the ischiocavernosus muscle with curved forceps, and then cut the ischiocavernosus muscle to expose the white tunica albuginea of the crus corpus cavernosum.</li>
		<li>Following the anatomical direction of the crus corpus cavernosum, carefully insert the needle into the crus corpus cavernosum through the white tunica albuginea. 
		NOTE: This is a crucial step for successful catheterization. A small amount of heparinized saline can be injected, and a slight penile tumescence should be observed, if the needle has been inserted correctly.</li>
		<li>Carefully release the needle and avoid any sliding of the needle or disruption of the connecting tube. Inspect for any leakage.</li>
	</ol>
	</li>
</ol>
3. Stimulate the CN
<ol>
	<li>Open the software program for pressure signal recording and start the pressure signal recording.</li>
	<li>Set the parameters of the stimulation: 15 Hertz, pulse width of 5 milliseconds, 5 volts, and a 60 s duration. Stimulate CN at a frequency of 15&#160;Hz with a pulse width of 5 ms. 
	NOTE: A sharp rise of the ICP can be observed while applying the electrical stimulation.</li>
	<li>Allow a 30-minute rest interval between stimulations. The maximum of consecutive stimulation in each animal is three times.</li>
</ol>
4. End the Procedure
<ol>
	<li>After recording, administer euthanasia by injecting an overdose of pentobarbital sodium at a dose of 150 mg/kg body weight. Confirm the death of rats by checking their arterial pressure. Remove the rats, and clean the surgery tools.</li>
</ol>
5. Data Analysis
<ol>
	<li>Save and export the data from the software. The response is commonly expressed as the ratio of ICP to systemic mean arterial pressure (MAP). The ratio of peak ICP/MAP was calculated to evaluate the erectile function.</li>
	<li>Pool data from at least five rats, and analyze with statistical software. Differences are considered statistically significant when p &#60; 0.05, using Student&#39;s t-test.</li>
</ol>

<ol><li><a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((NIH+Consensus+Conference.+Impotence.+NIH+Consensus+Development+Panel+on+Impotence%5BTitle%5D)+AND+%22JAMA%22%5BJournal%5D)">NIH Consensus Conference. Impotence. NIH Consensus Development Panel on Impotence.</a> JAMA. 270 (1), 83-90 (1993).</li>
<li>Chung, E., De Young, L., Brock, G. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Investigative+models+in+erectile+dysfunction%3A+a+state-of-the-art+review+of+current+animal+models%5BTitle%5D)+AND+%22J+Sex+Med%22%5BJournal%5D)">Investigative models in erectile dysfunction: a state-of-the-art review of current animal models.</a> J Sex Med. 8 (12), 3291-3305 (2011).</li>
<li>Lue, T. F., Takamura, T., Schmidt, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Hemodynamics+of+erection+in+the+monkey%5BTitle%5D)+AND+%22J+Urol%22%5BJournal%5D)">Hemodynamics of erection in the monkey.</a> J Urol. 130 (6), 1237-1241 (1983).</li>
<li>Carati, C. J., Creed, K. E., Keogh, E. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Autonomic+control+of+penile+erection+in+the+dog%5BTitle%5D)+AND+%22J+Physiol%22%5BJournal%5D)">Autonomic control of penile erection in the dog.</a> J Physiol. 384, 525-538 (1987).</li>
<li>Steers, W. D., Mallory, B., de Groat, W. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Electrophysiological+study+of+neural+activity+in+penile+nerve+of+the+rat%5BTitle%5D)+AND+%22Am+J+Physiol%22%5BJournal%5D)">Electrophysiological study of neural activity in penile nerve of the rat.</a> Am J Physiol. 254 (6 Pt 2), R989-R1000 (1988).</li>
<li>Kapoor, M. S., Khan, S. A., Gupta, S. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Animal+models+of+erectile+dysfunction%5BTitle%5D)+AND+%22J+Pharmacol+Toxicol+Methods%22%5BJournal%5D)">Animal models of erectile dysfunction.</a> J Pharmacol Toxicol Methods. 76, 43-54 (2015).</li>
<li>Burnett, A. L., Lowenstein, C. J., Bredt, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Nitric+oxide%3A+A+physiologic+mediator+of+penile+erection%5BTitle%5D)+AND+%22Science%22%5BJournal%5D)">Nitric oxide: A physiologic mediator of penile erection.</a> Science. 257 (5068), 401-403 (1992).</li>
<li>Oh, T. Y., Kang, K. K., Ahn, B. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Erectogenic+effect+of+the+selective+phosphodiesterase+type+5+inhibitor%2C+DA-8159%5BTitle%5D)+AND+%22Arch+Pharm+Res%22%5BJournal%5D)">Erectogenic effect of the selective phosphodiesterase type 5 inhibitor, DA-8159.</a> Arch Pharm Res. 23 (5), 471-476 (2000).</li>
<li>Ouyang, B., Sun, X., Han, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Human+urine-derived+stem+cells+alone+or+genetically-modified+with+FGF2+Improve+type+2+diabetic+erectile+dysfunction+in+a+rat+model%5BTitle%5D)+AND+%22PLoS+One%22%5BJournal%5D)">Human urine-derived stem cells alone or genetically-modified with FGF2 Improve type 2 diabetic erectile dysfunction in a rat model.</a> PLoS One. 9 (3), e92825(2014).</li>
<li>Pan, F., Xu, J., Zhang, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Identification+and+characterization+of+the+MicroRNA+profile+in+aging+rats+with+erectile+dysfunction%5BTitle%5D)+AND+%22J+Sex+Med%22%5BJournal%5D)">Identification and characterization of the MicroRNA profile in aging rats with erectile dysfunction.</a> J Sex Med. 11 (7), 1646-1656 (2014).</li>
<li>Cho, M. C., Park, K., Kim, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Restoration+of+erectile+function+by+suppression+of+corporal+apoptosis%2C+fibrosis+and+corporal+veno-occlusive+dysfunction+with+rho-kinase+inhibitors+in+a+rat+model+of+cavernous+nerve+injury%5BTitle%5D)+AND+%22J+Urol%22%5BJournal%5D)">Restoration of erectile function by suppression of corporal apoptosis, fibrosis and corporal veno-occlusive dysfunction with rho-kinase inhibitors in a rat model of cavernous nerve injury.</a> J Urol. 193 (5), 1716-1723 (2015).</li>
<li>Hannan, J. L., Matsui, H., Sopko, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Caspase-3+dependent+nitrergic+neuronal+apoptosis+following+cavernous+nerve+injury+is+mediated+via+RhoA+and+ROCK+activation+in+major+pelvic+ganglion%5BTitle%5D)+AND+%22Sci+Rep%22%5BJournal%5D)">Caspase-3 dependent nitrergic neuronal apoptosis following cavernous nerve injury is mediated via RhoA and ROCK activation in major pelvic ganglion.</a> Sci Rep. 6, 29416(2016).</li>
<li>Heaton, J. P., Varrin, S. J., Morales, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+characterization+of+a+bio-assay+of+erectile+function+in+a+rat+model%5BTitle%5D)+AND+%22J+Urol%22%5BJournal%5D)">The characterization of a bio-assay of erectile function in a rat model.</a> J Urol. 145 (5), 1099-1102 (1991).</li>
<li>Mehta, N., Sikka, S., Rajasekaran, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Rat+as+an+animal+model+for+male+erectile+function+evaluation+in+sexual+medicine+research%5BTitle%5D)+AND+%22J+Sex+Med%22%5BJournal%5D)">Rat as an animal model for male erectile function evaluation in sexual medicine research.</a> J Sex Med. 5 (6), 1278-1283 (2008).</li>
<li>Quinlan, D. M., Nelson, R. J., Partin, A. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+rat+as+a+model+for+the+study+of+penile+erection%5BTitle%5D)+AND+%22J+Urol%22%5BJournal%5D)">The rat as a model for the study of penile erection.</a> J Urol. 141 (3), 656-661 (1989).</li>
<li>Albersen, M., Orabi, H., Lue, T. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Evaluation+and+treatment+of+erectile+dysfunction+in+the+aging+male%3A+A+mini-review%5BTitle%5D)+AND+%22Gerontology%22%5BJournal%5D)">Evaluation and treatment of erectile dysfunction in the aging male: A mini-review.</a> Gerontology. 58 (1), 3-14 (2012).</li>
<li>Hedlund, P., Matsumoto, K., Andersson, K. -E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Animal+Models+of+Erectile+Dysfunction%5BTitle%5D)+AND+%22Curr+Prot+Pharmacol%22%5BJournal%5D)">Animal Models of Erectile Dysfunction.</a> Curr Prot Pharmacol. 29, 5.41.1-5.41.22 (2005).</li>
<li>Giuliano, F., Bernabe, J., Rampin, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Telemetric+monitoring+of+intracavernous+pressure+in+freely+moving+rats+during+copulation%5BTitle%5D)+AND+%22J+Urol%22%5BJournal%5D)">Telemetric monitoring of intracavernous pressure in freely moving rats during copulation.</a> J Urol. 152 (4), 1271-1274 (1994).</li>
<li>Bernabe, J., Rampin, O., Giuliano, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Intracavernous+pressure+changes+during+reflexive+penile+erections+in+the+rat%5BTitle%5D)+AND+%22Physiol+Behav%22%5BJournal%5D)">Intracavernous pressure changes during reflexive penile erections in the rat.</a> Physiol Behav. 57 (5), 837-841 (1995).</li>
<li>Bernabe, J., Rampin, O., Sachs, B. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Intracavernous+pressure+during+erection+in+rats%3A+an+integrative+approach+based+on+telemetric+recording%5BTitle%5D)+AND+%22Am+J+Physiol%22%5BJournal%5D)">Intracavernous pressure during erection in rats: an integrative approach based on telemetric recording.</a> Am J Physiol. 276 (2 Pt 2), R441-R449 (1999).</li>
<li>Adachi, H., Kodama, K., Ishihara, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Evaluation+of+erectile+response+by+continuous+measurement+of+penile+diameter+in+rats%5BTitle%5D)+AND+%22J+Pharmacol+Toxicol+Methods%22%5BJournal%5D)">Evaluation of erectile response by continuous measurement of penile diameter in rats.</a> J Pharmacol Toxicol Methods. 41 (4), 147-152 (1999).</li>
</ol>

The authors have nothing to disclose

As a direct measure of erectile function, ICP is a reliable method14. It allows for the acquisition of data on basal ICP, peak ICP, plateau ICP, time to erection and detumescence time, duration of response, etc. Besides these direct measured parameters, there are some other index parameters: (1) &#34;T80&#34;, the time to reach 80% of peak ICP; (2) &#34;D20&#34;, the time to decrease to 20% of peak ICP; (3) &#34;&#916;T80&#34;, the rate of increase in pressure (per second) at T80; and (4)...

ED is defined as the inability to attain or keep a penile erection, and has become a common male sexual disorder1. Experimental animals are used and provide reproducible models to investigate erectile function2. For a long time, several larger animal models have been employed for investigating erectile function3,4,5. Although rodents are relatively small compared to other animals, they are also used for the study of male erectile dysfunction due to exhibiting several advantages6. First, the morphological and functional sexual characteristics of humans are recapitulated in rodents. Second, compared to larger animals used in ED studies, rodents are more economical to purchase, house, and maintain. Third, genetically modified rodent models provide advantages in reproducible and subsequent behavioral as well as neurophysiological studies. Therefore, rodents have quickly become the primary animals used in the study of male erectile dysfunction.
Benefiting from a pure genetic background and consistent culture conditions, rodent models have provided consistently reproducible data5,6,7,8. Among the numerous available studies related to many aspects of erectile functions, the apomorphine (APO)-induced erectile response test and the electric-stimulation-induced ICP response test are the most widely used methods that reliably reflect erectile function9,10,11,12. The APO-induced erectile function test, developed by Heaton et al.13, is a bio-assay that utilizes the phenomenon that administration of apomorphine to rats elicits erections and yawns. As an easy, noninvasive, and stable bio-assay to evaluate erectile function, the APO-induced erectile function test is widely used in many studies. However, this assay does not adequately reflect the quality of erections or the dynamic changes in blood flow associated with an erectile response14. ICP measurements were initially developed by Quinlan et al.15. In this method, a catheter is placed into the carotid artery to measure systemic blood pressure, and another catheter is inserted into the crus corpus cavernosum to record the ICP. Before or during the ICP recording, a vasoactive agent and/or electrical field stimulation of the major pelvic ganglion (MPG) or CN were often given to the rats14. This assay has been a reliable tool for evaluating the therapies and medicines for ED, and will likely be used as a vital evaluation method in the future6.
Compared to the easily-performed APO-induced erectile function test, successful ICP recordings require attention to detail, practice, and adherence to the operation method. Therefore, here, we provide a detailed description of how to perform ICP recording.

<table><tbody><tr><td>&lt;strong&gt;Animal&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Rats</td><td></td><td></td><td>Strain: Sprague-Dawley Age: 2-3 month</td></tr><tr><td>Rats</td><td></td><td></td><td>Strain: Sprague-Dawley Age: 15-18 month</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Reagents&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Saline</td><td>Sigma-Aldrich, S7653</td><td></td><td>dissolve 8.5 gram sodium chloride in distilled water</td></tr><tr><td>Pentobarbital sodium solution</td><td>Sigma-Aldrich, P3761</td><td></td><td>dissolve 1 gram in 100 ml saline</td></tr><tr><td>Povidone-iodine</td><td>BTP Pharmaceutical Co. Limited</td><td></td><td>10% (V/V)</td></tr><tr><td>Ethanol</td><td>China National Pharmaceutical Group Corporation (SINOPHARM)</td><td></td><td>70% (V/V)</td></tr><tr><td>Heparin</td><td>Sigma-Aldrich, H3149</td><td></td><td>dissolve 20000U heparin in 100 ml saline</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Materials&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Hypodermic needle</td><td>Shandong Weigao Group Medical Polymer Co., Ltd.&amp;nbsp;</td><td>23G</td><td></td></tr><tr><td>Syringe</td><td>Shandong Weigao Group Medical Polymer Co., Ltd</td><td>10 ml</td><td></td></tr><tr><td>Three-way stopcock</td><td>Chengdu Instrument factory</td><td>TSK 01</td><td></td></tr><tr><td>Electrode</td><td>Chengdu Instrument factory</td><td>JST-1</td><td></td></tr><tr><td>Catheter tube</td><td>Chengdu Instrument factory</td><td>PE-10, PE-50</td><td></td></tr><tr><td>Operating scissors</td><td>Shanghai operation equipment factory</td><td>J22010, J22020</td><td></td></tr><tr><td>Ophthalmic operating scissors</td><td>Shanghai operation equipment factory</td><td>Y00010, Y00020</td><td></td></tr><tr><td>Ophthalmic forceps</td><td>Shanghai operation equipment factory</td><td>JD1010, JD1020</td><td></td></tr><tr><td>MicroScissors</td><td>World Precision Instruments</td><td>WAA260</td><td></td></tr><tr><td>silk suture</td><td>Shandong Weigao Group Medical Polymer Co., Ltd.&amp;nbsp;</td><td>5-0</td><td></td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Equipment&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Stimulator</td><td>Nanjing medease science and technology co. ltd (model 4C501H)</td><td></td><td>15 Hz, 5 ms pulse, 5 V, 60 s duration and 5 minutes interval</td></tr><tr><td>Multichannel signal collection processing system</td><td>Nanjing medease science and technology co. ltd (model 4C501H)</td><td></td><td>Blood pressure model</td></tr><tr><td>Pressure transducer</td><td>Beijing Xin Hang Xing Ye Technology Trading Company Limited (model YP100)</td><td></td><td>40KPa</td></tr></tbody></table>

intracavernosal pressure recording to evaluate erectile function in rodents

Intracavernosal Pressure Recording to Evaluate Erectile Function in Rodents

Erectile dysfunction (ED) is defined as the inability to attain or keep an erection of the penis, and this has become a prevalent male sexual disorder. Rodents are employed by many studies to research the physiology/pathology of erectile function. Erectile function in rodents can be evaluated by measuring the intracavernosal pressure (ICP). In practice, ICP can be monitored following electrical stimulation of the cavernous nerves (CNs). The arterial pressure of the carotid artery (the mean arterial pressure) is used as the reference for ICP. Using ICP recording protocols, many key parameters of erectile function can be measured from the ICP response curve. The ICP measurement provides more information than the apomorphine-induced penile erection test, and is cheaper than telemetric monitoring of the corpus spongiosum penis, making this method the most popular one to evaluate erectile function. However, compared to the easily-performed APO-induced erectile function test, successful ICP recordings require attention to detail, practice, and adherence to the operation method. In this work, an introduction to ICP recording in rats is provided to complement the procedure efficiently.

Numerous studies have shown that erectile dysfunction in aged males is becoming a common problem. However, medical treatment is limited in the management of aging-related ED16. In rodent models of aging-related ED, many therapies are tested on the erectile function of aged rats. As we have introduced above, the ICP recording test could be used to distinguish the ED animals from the total population of experimental animals, which is also valuable to quantify the eff...

Intracavernosal pressure recording (ICP) is an important method to evaluate the erectile function of experimental animals. Here, a detailed protocol is demonstrated for the recording procedure of ICP by catheterizing the crura penis and then electrically stimulating the cavernous nerves in rats.

Erectile dysfunction (ED) is defined as the inability to attain or keep an erection of the penis, and this has become a prevalent male sexual disorder. ...

intracavernosal-pressure-recording-to-evaluate-erectile-function

Research

JoVE Journal

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This study describes a simplified surgical procedure and technique for performing cavernous nerve stimulation with the isolation of the nerve-electrode complex using silicone glue and intracavernous pressure measurement.

Cavernous Nerve Stimulation and Recording of Intracavernous Pressure in a Rat

Here, we describe a setup for simultaneous recording of electrocardiography and intra-arterial blood pressure (BP) in experimental rats, which can be done with standard equipment in animal facilities and can be applied to physiological or pharmacological studies to investigate pathogenic or therapeutic mechanisms in cardiovascular medicine.

Simultaneous Electrocardiography Recording and Invasive Blood Pressure Measurement in Rats

This protocol describes the procedure for measuring ATP concentrations in the lumen of the bladder in an anesthetized rodent.

In Vivo Luminal Measurement of Distension-Evoked Urothelial ATP Release in Rodents

The monitoring of extracellular neurotransmitter levels in distinct brain regions of  freely moving animals offers insights on the link between neurotransmitter release and behavior. In vivo microdialysis coupled with electrochemical detection provides excellent anatomical and chemical resolution; and information on how basal neurotransmission is altered by pharmacological or physiological manipulations.

Survivable Stereotaxic Surgery in Rodents 

Learn intracavernosal pressure recording to evaluate erectile function in rats using catheterization and cavernous nerve stimulation. This method enables precise assessment of erectile response for urology research.

Intracavernosal Pressure Recording to Evaluate Erectile Function in Rodents

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