C.D.M. was supported by the American College of Surgeons (ACS) Resident Research Scholarship. M.S.H. was supported by the California Institute for Regenerative Medicine (CIRM) Clinical Fellow training grant TG2-01159. M.S.H., H.P.L., and M.T.L. were supported by the American Society of Maxillofacial Surgeons (ASMS)/Maxillofacial Surgeons Foundation (MSF) Research Grant Award. H.P.L. was supported by NIH grant R01 GM087609 and a gift from Ingrid Lai and Bill Shu in honor of Anthony Shu. H.P.L. and M.T.L. were supported by the Hagey Laboratory for Pediatric Regenerative Medicine and The Oak Foundation. M.T.L. was supported by the Gunn/Olivier Fund.

The following protocol has been approved by the Stanford University Institutional Animal Care and Use Committee (IACUC) and complies with all institutional ethical guidelines regarding the use of research animals.
1. Creation of Abdominal Adhesions
<ol>
	<li>Start the mouse on antibiotic chow diet one week prior to the procedure.</li>
	<li>Autoclave the surgical instruments and pre-warm the saline irrigation solution.</li>
	<li>Anesthetize the mouse using 2% inhaled isoflurane.</li>
	<li>Using a hair clipper followed by a quick application (5 - 10 sec) of depilatory agent, remove the hair from the majority of the surface of the abdomen. Thoroughly remove the depilatory agent by gently wiping with wet gauze and, optionally, by carefully dunking the lower half of the mouse into warm water. Thoroughly dry the animal.</li>
	<li>Place the animal&#39;s snout into the anesthetic nose cone. During the entire surgery, carefully monitor the respiratory rate of the animal and titrate the anesthetic flow rate as needed.</li>
	<li>Use a warming device, such as a heating pad or a warming lamp, to prevent hypothermia.</li>
	<li>Prior to prepping the abdomen, secure the mouse with strips of tape placed above and below the abdomen to prevent the mouse from shifting during surgery. Disinfect the abdomen with betadine, then follow with 70% ethanol. Include as much area as possible in the prep, including the hair on the edges of the shaved area. Place a sterile drape over the mouse. (Figure 1)</li>
	<li>Subcutaneously inject 0.1 mg/kg buprenorphine, or 3 &#181;g for a 30 g mouse.</li>
	<li>Make the skin incision.
	<ol>
		<li>Starting in the lower abdominal midline, grasp the skin with forceps and make a shallow vertical cut in the skin using sharp scissors.</li>
		<li>Carry the cut superiorly to the xyphoid with the scissors. Take care to enter only the skin.</li>
	</ol>
	</li>
	<li>As the abdominal musculature is now visible covering the viscera, grasp the midline of the musculature with forceps and very carefully make a small cut into it using sharp scissors. Make sure not to accidentally cut into an abdominal organ.</li>
	<li>After entering the peritoneal space with a small cut and seeing the muscular layer pull away from the abdominal organs, extend the cut superiorly and inferiorly by inserting the scissors into the opening and carefully cutting in both directions. Extend the incision from the xyphoid superiorly to above the bladder inferiorly. (Figure 2)</li>
	<li>Now that the intestines are exposed, locate the cecum and gently exteriorize it. Avoid grasping the cecum with toothed or sharp forceps. Instead use an atraumatic forceps such as an Adson serrated forceps.</li>
	<li>Abrade the cecum with sandpaper.
	<ol>
		<li>Gently abrade the entire surface of both sides of the cecum with 100 grit sandpaper for 30 - 60 sec until the surface becomes less shiny and petechiae appear on the surface. If the surgeon is right-handed, it helps to orient the cecum with the tip facing to the right and drape the cecum over the surgeon&#39;s left index finger. (Figure 3)</li>
		<li>Perform the sanding gently, as it is easy to accidentally cause a perforation of the thin cecal wall. A small amount of grittiness should be felt as the sandpaper is moved along the cecal surface. If the sandpaper is felt repeatedly catching on the cecum, this will likely cause a tear in the cecal wall. Watch carefully to ensure that particles of sandpaper do not dislodge and remain in the abdomen, as this may cause excessive foreign body reaction.</li>
		<li>If a tear in the cecal wall occurs, terminate the procedure and euthanize the animal.</li>
		<li>If a cecal blood vessel is sheared by the sandpaper and causes bleeding, hold pressure for up to two minutes with gauze. However, if bleeding persists after this time, place a figure-of-eight 7-0 monofilament suture around the point of bleeding. This will reliably stop the bleeding in almost all cases. Take care not to incorporate a large amount of cecal wall into the suture, as this risks causing necrosis of the involved part of the wall.</li>
	</ol>
	</li>
	<li>Injure the right abdominal sidewall.
	<ol>
		<li>Use a strip of sandpaper to abrade the peritoneal surface of the muscle of the right abdominal sidewall. Be more aggressive with the sanding here than on the cecum and continue until the entire surface of the right abdominal sidewall appears roughed up. Avoid sanding so hard that skin is visible through openings in the muscular layer. (Figure 4)</li>
		<li>Using a Castro-Viejo needle driver, place between two and four figure-of-eight 4-0 silk stitches into the muscular layer of the right abdominal sidewall. Leave the tails about 5 mm long. Take care not to accidentally catch bowel wall into the suture. (Figure 5)</li>
	</ol>
	</li>
	<li>Using a 10 ml syringe filled with warmed saline, irrigate the intestines several times. Direct the stream of saline into the abdominal cavity to irrigate the interior as well. If the surface underneath the mouse becomes soaked, move the mouse over or replace the surface, in order to avoid hypothermia.</li>
	<li>Use a sterile gauze placed over the incision to soak up excess irrigation.</li>
	<li>Take a pinch of starch and sprinkle it onto the surface of the right abdominal sidewall and onto both sides of the cecum. (Figure 6)</li>
	<li>Make sure that there is no active bleeding. If there is, use a gauze sponge to apply pressure directly onto the point of bleeding until it stops. If the bleeding does not stop readily, place a hemostatic suture as described above.</li>
	<li>Using the blunt end of the forceps and a finger, gently push the intestines back into the abdominal cavity. Position the cecum next to the sutures in the right abdominal sidewall in order to maximize adhesion formation.</li>
	<li>Close the abdominal incision.
	<ol>
		<li>Using 6-0 absorbable braided suture, place a running stitch into the muscular layer at the top of the incision.</li>
		<li>Run the suture down toward the bottom of the incision, bringing together the muscular layer. Travel by about 3 mm and take 3 mm bites with each new stitch. Take care not to accidentally take a bite of intestine while placing sutures.</li>
		<li>At the bottom of the incision, leave a loop of suture from the previous bite and use this to instrument tie the suture. Cut the suture leaving 5 mm tails.</li>
		<li>Repeat the above three steps with 6-0 nylon monofilament suture to close the skin.</li>
	</ol>
	</li>
	<li>Administer a 20 ml/kg subcutaneous saline bolus (roughly 0.5 ml for a 30 g mouse).</li>
	<li>Using a dry gauze, thoroughly dry the entire animal, as the dorsal fur tends to get wet during irrigation.</li>
	<li>Loosely wrap an adhesive dressing around the abdomen to cover the incision. Take care not to constrain the animal&#39;s legs or breathing mechanics with the dressing.</li>
	<li>Carefully monitor the animal as it recovers from anesthesia.&#160;Administer buprenorphine every 12 hr for 2-3 days after the procedure for pain control.</li>
</ol>
2. Harvesting Adhesion Tissue
<ol>
	<li>Wait a minimum of seven days after the initial surgery. Again, autoclave surgical instruments and anesthetize the mouse with isoflurane.</li>
	<li>Sterilize the abdomen with betadine followed by 70% ethanol. Shave and depilate additional hair from the right side of the abdomen so that the adhesion specimen containing skin will not be covered in hair, which makes histology more difficult.</li>
	<li>Use a left paramedian incision, since bowel is often stuck to the original incision. Starting at the lower end of the abdomen, about 5 mm to the left of the bottom of the original incision, grasp the skin with small toothed forceps and cut into the skin with sharp scissors. Extend this cut superiorly to the ribcage. (Figure 7)</li>
	<li>Using scissors, cut into the muscular layer and after entering the peritoneal space, extend the cut to the top and bottom of the incision. There will be adhesive tissue causing the cecum and small bowel to adhere to the right sidewall of the abdomen and possibly also to the original incision. (Figure 8)</li>
	<li>Using the scissors and starting on the edge of the incision, above the level of the cecum, start cutting into the abdominal wall in a circle around the area where the bowel is adherent.</li>
	<li>Alternating above and below the level of the cecum, gradually cut all the way around the adhesion and complete the circle, yielding an &#34;island&#34; of skin and abdominal wall adherent to the bowel. (Figure 9)</li>
	<li>Again using the scissors, cut into the bowel and separate the adherent part from the rest of the bowel, yielding a sandwich of tissue that consists of skin and abdominal wall on one side, bowel on the other side, and adhesive tissue connecting the two in between. (Figure 10)</li>
	<li>Optionally, use a pointed scissors to sharply separate the skin from the abdominal wall muscle. For histology consider leaving the skin attached, but for digestion and cell isolation the skin can be removed. If the tissue will be used for histology, make sure to remove as much suture material as possible without excessively disturbing the adhesive interface. For digestion and cell isolation it is acceptable to leave the sutures in place as long as the tissue digest is filtered.</li>
	<li>After excising adhesion tissue, euthanize the mouse using a humane method approved by your institutional animal use committee.&#160;</li>
</ol>

<ol>
	<li>Ellis, 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=Adhesion-related+hospital+readmissions+after+abdominal+and+pelvic+surgery:+a+retrospective+cohort+study.">Adhesion-related hospital readmissions after abdominal and pelvic surgery: a retrospective cohort study.</a> Lancet. 353 (9163), 1476-1480 (1999).</li><li>Brochhausen, 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=Current+strategies+and+future+perspectives+for+intraperitoneal+adhesion+prevention.">Current strategies and future perspectives for intraperitoneal adhesion prevention.</a> J Gastrointest Surg. 16 (6), 1256-1274 (2012).</li><li>diZerega, G. S., Campeau, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peritoneal+repair+and+post-surgical+adhesion+formation.">Peritoneal repair and post-surgical adhesion formation.</a> Hum Reprod Update. 7 (6), 547-555 (2001).</li><li>Hellebrekers, B. W., Kooistra, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogenesis+of+postoperative+adhesion+formation.">Pathogenesis of postoperative adhesion formation.</a> Br J Surg. 98 (11), 1503-1516 (2011).</li><li>Herrick, S. 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=Human+peritoneal+adhesions+are+highly+cellular,+innervated,+and+vascularized.">Human peritoneal adhesions are highly cellular, innervated, and vascularized.</a> J Pathol. 192 (1), 67-72 (2000).</li><li>Beyene, R. T., Kavalukas, S. L., Barbul, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intra-abdominal+adhesions:+Anatomy,+physiology,+pathophysiology,+and+treatment.">Intra-abdominal adhesions: Anatomy, physiology, pathophysiology, and treatment.</a> Curr Probl Surg. 52 (7), 271-319 (2015).</li><li>ten Broek, R. 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=Benefits+and+harms+of+adhesion+barriers+for+abdominal+surgery:+a+systematic+review+and+meta-analysis.">Benefits and harms of adhesion barriers for abdominal surgery: a systematic review and meta-analysis.</a> Lancet. 383 (9911), 48-59 (2014).</li><li>Becker, J. 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=Prevention+of+postoperative+abdominal+adhesions+by+a+sodium+hyaluronate-based+bioresorbable+membrane:+a+prospective,+randomized,+double-blind+multicenter+study.">Prevention of postoperative abdominal adhesions by a sodium hyaluronate-based bioresorbable membrane: a prospective, randomized, double-blind multicenter study.</a> J Am Coll Surg. 183 (4), 297-306 (1996).</li><li>Cassidy, M. R., Sherburne, A. C., Heydrick, S. J., Stucchi, A. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combined+intraoperative+administration+of+a+histone+deacetylase+inhibitor+and+a+neurokinin-1+receptor+antagonist+synergistically+reduces+intra-abdominal+adhesion+formation+in+a+rat+model.">Combined intraoperative administration of a histone deacetylase inhibitor and a neurokinin-1 receptor antagonist synergistically reduces intra-abdominal adhesion formation in a rat model.</a> Surgery. 157 (3), 581-589 (2015).</li><li>Thaler, 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=Coincidence+of+connective+tissue+growth+factor+expression+with+fibrosis+and+angiogenesis+in+postoperative+peritoneal+adhesion+formation.">Coincidence of connective tissue growth factor expression with fibrosis and angiogenesis in postoperative peritoneal adhesion formation.</a> Eur Surg Res. 37 (4), 235-241 (2005).</li><li>Hong, G. S., 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+macrophage-dependent+peroxisome+proliferator-activated+receptor+gamma+signalling+on+adhesion+formation+after+abdominal+surgery+in+an+experimental+model.">Effects of macrophage-dependent peroxisome proliferator-activated receptor gamma signalling on adhesion formation after abdominal surgery in an experimental model.</a> Br J Surg. 102 (12), 1506-1516 (2015).</li><li>Whang, 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=In+search+of+the+best+peritoneal+adhesion+model:+comparison+of+different+techniques+in+a+rat+model.">In search of the best peritoneal adhesion model: comparison of different techniques in a rat model.</a> J Surg Res. 167 (2), 245-250 (2011).</li><li>Buckenmaier, C. C., Pusateri, A. E., Harris, R. A., Hetz, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+antiadhesive+treatments+using+an+objective+rat+model.">Comparison of antiadhesive treatments using an objective rat model.</a> Am Surg. 65 (3), 274-282 (1999).</li><li>Rajab, T. 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=An+improved+model+for+the+induction+of+experimental+adhesions.">An improved model for the induction of experimental adhesions.</a> J Invest Surg. 23 (1), 35-39 (2010).</li></ol>

The authors declare that they have no competing financial interests.

The critical steps in this procedure are: thoroughly abrading the cecum without causing perforation, placing sutures in the abdominal sidewall, and applying the right amount of starch. Only apply sandpaper to the cecum, or to a small specific portion of the bowel. Wide use of sandpaper on large amounts of small bowel tends to cause significant ileus. Take care to abrade the cecum with enough force that the surface becomes rough, but not so much that the wall tears. Finding this balance can take some time. Always handle t...

Abdominal adhesions are a form of scar tissue that form in the abdomen in response to inflammation, typically following surgery or intraabdominal infection. Adhesions are a major cause of chronic abdominal pain and infertility, and are the most common cause of small bowel obstruction1. The presence of adhesions makes performing a second abdominal operation more difficult and increases the likelihood of complications2.
Despite years of research, the mechanisms underlying the formation of adhesions remain poorly understood. It is known that an initial injury to the peritoneal surface causes an exudation of fibrin-rich fluid, which then forms a clot that binds the surfaces of bowel and the abdominal wall together3. Later, fibroblasts and other cells migrate into the adhesive space and secrete connective tissue4. Over months to years the adhesion matures by developing blood vessels and nerves5.
Several commercial products exist that are designed to reduce the formation of adhesions after abdominal surgery (e.g., Seprafilm). All of these products act as mechanical barriers and stop adhesion formation by preventing physical contact between loops of bowel and the abdominal wall6,7. Despite evidence from a controlled trial that a surgical adhesion barrier reduces the formation of adhesions8, many surgeons anecdotally have been disappointed with the effectiveness of mechanical barrier products.
Currently there are no drug-based anti-adhesion therapies, which reflects the fact that the precise processes involved in adhesion formation are poorly understood. Developing a therapy that specifically targets cellular or molecular agents involved in the formation of adhesions will require an improved understanding of the events that are involved in the formation of the adhesion. Several groups have identified molecular pathways that may be important for adhesion formation9-11. Animal models provide a superb environment for studying the formation of adhesions. Many studies have been published describing the surgical creation of adhesion in several animals, particular the rat and mouse6,12-14. Given our experience with studying fibrosis in the mouse and the wide availability of transgenic mice and mouse-based antibodies, we chose the mouse as our model for the study of adhesions. Herein, we report the technique that we have developed to reproducibly and reliably create abdominal adhesions in the mouse.

<table border="0" cellpadding="0" cellspacing="0" width="612">
	<tbody>
		<tr height="63">
			<td height="63" style="height:63px;width:152px;">Fisherbrand Absorbent Underpads, 20&#34; x 24&#34;</td>
			<td style="width:136px;">Fisher Scientific</td>
			<td style="width:116px;">14-206-62</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">Polylined Sterile Field, 18&#34; x 24&#34;</td>
			<td style="width:136px;">Busse Hospital Disposables</td>
			<td style="width:116px;">696</td>
			<td style="width:208px;">Cut a rectangular hole of the appropriate size</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:152px;">Isothesia isoflurane</td>
			<td style="width:136px;">Henry Schein&#160;</td>
			<td style="width:116px;">050033</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:152px;">Fisherbrand Sterile cotton gauze pad, 4&#34; x 4&#34;</td>
			<td style="width:136px;">Fisher Scientific</td>
			<td style="width:116px;">22-415-469</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:152px;">Puralube petrolatum ophthalmic ointment, 1/8 oz. tube</td>
			<td style="width:136px;">Dechra Veterinary Products</td>
			<td style="width:116px;">NDC 17033-211-38</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">Nair depilatory cream</td>
			<td style="width:136px;">Church &#38; Dwight Co.</td>
			<td style="width:116px;">22339-05</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:152px;">Buprenex buprenorphine&#160; 0.3 mg/mL</td>
			<td style="width:136px;">Reckitt Benckiser Pharmaceuticals Inc.</td>
			<td style="width:116px;">NDC 12496-0757-5</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">1 cc insulin syringe, 27G</td>
			<td style="width:136px;">Becton&#160; Dickinson</td>
			<td style="width:116px;">329412</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">Povidone Iodine Prep Solution</td>
			<td style="width:136px;">Medline</td>
			<td style="width:116px;">MDS093944H</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">Webcol alcohol prep swabs</td>
			<td style="width:136px;">Covidien</td>
			<td style="width:116px;">6818</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:152px;">General-Purpose Labarotory Labeling tape</td>
			<td style="width:136px;">VWR</td>
			<td style="width:116px;">89097-912</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">BioGel PI surgical gloves</td>
			<td style="width:136px;">M&#246;lnlycke Health Care</td>
			<td style="width:116px;">ALA42675Z</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">Micro Forceps with teeth</td>
			<td style="width:136px;">Roboz</td>
			<td style="width:116px;">RS-5150</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:152px;">Fine scissors- sharp</td>
			<td style="width:136px;">Fine Science Tools</td>
			<td style="width:116px;">14060-09</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">Straight serrated forceps</td>
			<td style="width:136px;">Fine Science Tools</td>
			<td style="width:116px;">11050-10</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">Castro-Viejo needle driver</td>
			<td style="width:136px;">Fine Science Tools</td>
			<td style="width:116px;">12565-14</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">100 grit 1/4 sheet sandpaper</td>
			<td style="width:136px;">ACE Hardware</td>
			<td style="width:116px;">1010446</td>
			<td style="width:208px;">Cut into strips</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">4-0 silk suture, 30&#34;, SH needle</td>
			<td style="width:136px;">Ethicon</td>
			<td style="width:116px;">K831</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:152px;">7-0 PDS II absorbable monofilament suture, 30&#34;, BV-1 needle</td>
			<td style="width:136px;">Ethicon</td>
			<td style="width:116px;">Z135</td>
			<td style="width:208px;">Usually comes double-armed. Cut the suture at the midway point to generate two usable sutures.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:152px;">Rice starch</td>
			<td style="width:136px;">MP Biomedicals</td>
			<td style="width:116px;">102955</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:152px;">0.9% Sodium Chloride Irrigation</td>
			<td style="width:136px;">Baxter</td>
			<td style="width:116px;">BHL2F7121</td>
			<td style="width:208px;">Warm to 37&#176; C prior to use</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:152px;">10 mL syringe</td>
			<td style="width:136px;">Becton Dickinson</td>
			<td style="width:116px;">309604</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:152px;">6-0 Vicryl absorbable braided suture, 18&#34;, RB-1 taper needle</td>
			<td style="width:136px;">Ethicon</td>
			<td style="width:116px;">J212H</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:152px;">6-0 Ethilon nylon monofilament&#160; suture, 18&#34;, P-3 needle,&#160;</td>
			<td style="width:136px;">Ethicon</td>
			<td style="width:116px;">1698G</td>
			<td style="width:208px;"></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:152px;">Tegaderm Transparent Film Dressing Frame Style, 6 cm x 7 cm</td>
			<td style="width:136px;">3M</td>
			<td style="width:116px;">1624W</td>
			<td style="width:208px;">Cut in half lengthwise</td>
		</tr>
	</tbody>
</table>

creation of abdominal adhesions in mice

Abdominal adhesions consist of fibrotic tissue that forms in the peritoneal space in response to an inflammatory insult, typically surgery or intraabdominal infection. The precise mechanisms underlying adhesion formation are poorly understood. Many compounds and physical barriers have been tested for their ability to prevent adhesions after surgery with varying levels of success. The mouse and rat are important models for the study of abdominal adhesions. Several different techniques for the creation of adhesions in the mouse and rat exist in the literature. Here we describe a protocol utilizing abrasion of the cecum with sandpaper and sutures placed in the right abdominal sidewall. The mouse is anesthetized and the abdomen is prepped. A midline laparotomy is created and the cecum is identified. Sandpaper is used to gently abrade the surface of the cecum. Next, several figure-of-eight sutures are placed into the peritoneum of the right abdominal sidewall. The abdominal cavity is irrigated, a small amount of starch is applied, and the incision is closed. We have found that this technique produces the most consistent adhesions with the lowest mortality rate.

At seven days after surgery, the cecum and possibly ascending colon, liver, and loops of small bowel should be adherent to the right-sided abdominal wall. (Figure 8) Excised tissue can be embedded and sectioned and will yield excellent histological slides. (Figure 11, 12)
When the procedure is performed properly, 100% of mice should have substantial adhesions at seven days. Mortality should be l...

Watch this Scientific Journal Video about Creation of Abdominal Adhesions in Mice at JoVE.com

Creation of Abdominal Adhesions in Mice

Abdominal adhesions that form after surgery are a major cause of pain, infertility, and hospitalization and reoperation for small bowel obstruction. Our surgical procedure for creating abdominal adhesions in mice is a reliable tool to study the mechanisms underlying the formation of adhesions.

Abdominal adhesions consist of fibrotic tissue that forms in the peritoneal space in response to an inflammatory insult, typically surgery or ...

Research

JoVE Journal

Medicine

12.5K Views.  Stanford University School of Medicine. Abdominal adhesions that form after surgery are a major cause of pain, infertility, and hospitalization and reoperation for small bowel obstruction. Our surgical procedure for creating abdominal adhesions in mice is a reliable tool to study the mechanisms underlying the formation of adhesions.

Video: Creation of Abdominal Adhesions in Mice

The C-seal: A Biofragmentable Drain Protecting the Stapled Colorectal Anastomosis from Leakage

Colorectal anastomotic leakage (AL) is a serious complication in colorectal surgery leading to high morbidity and mortality rates1. The incidence of AL varies between 2.5 and 20% 2-5. Over the years, many strategies aimed at lowering the incidence of anastomotic leakage have been examined6, 7. 
The cause of AL is probably multifactorial. Etiological factors include insufficient arterial blood supply, tension on the anastomosis, hematoma and/or infection at the anastomotic site, and co-morbid factors of the patient as diabetes and atherosclerosis8. Furthermore, some anastomoses may be insufficient from the start due to technical failure.
Currently a new device is developed in our institute aimed at protecting the colorectal anastomosis and lowering the incidence of AL. This so called C-seal is a biofragmentable drain, which is stapled to the anastomosis with the circular stapler. It covers the luminal side of the colorectal anastomosis thereby preventing leakage.
The C-seal is a thin-walled tube-like drain, with an approximate diameter of 4 cm and an approximate length of 25 cm (figure 1). It is a tubular device composed of biodegradable polyurethane. Two flaps with adhesive tape are found at one end of the tube. These flaps are used to attach the C-seal to the anvil of the circular stapler, so that after the anastomosis is made the C-seal can be pulled through the anus. The C-seal remains in situ for at least 10 days. Thereafter it will lose strength and will degrade to be secreted from the body together with the gastrointestinal natural contents.
The C-seal does not prevent the formation of dehiscences. However, it prevents extravasation of faeces into the peritoneal cavity. This means that a gap at the anastomotic site does not lead to leakage.
Currently, a phase II study testing the C-seal in 35 patients undergoing (colo-)rectal resection with stapled anastomosis is recruiting. The C-seal can be used in both open procedures as well as laparoscopic procedures. The C-seal is only applied in stapled anastomoses within 15cm from the anal verge. In the video, application of the C-seal is shown in an open extended sigmoid resection in a patient suffering from diverticular disease with a stenotic colon.

The C-seal is a biofragmentable drain protecting the stapled colorectal anastomosis. In this video, details of the manufacturing, deployment and use are shown.

Colorectal anastomotic leakage (AL) is a serious complication in colorectal surgery leading to high morbidity and mortality rates1. The incidence of AL ...

Thermal Ablation for the Treatment of Abdominal Tumors

Percutaneous thermal ablation is an emerging treatment option for many tumors of the abdomen not amenable to conventional treatments. During a thermal ablation procedure, a thin applicator is guided into the target tumor under imaging guidance. Energy is then applied to the tissue until temperatures rise to cytotoxic levels (50-60 &deg;C). Various energy sources are available to heat biological tissues, including radiofrequency (RF) electrical current, microwaves, laser light and ultrasonic waves. Of these, RF and microwave ablation are most commonly used worldwide.
During RF ablation, alternating electrical current (~500 kHz) produces resistive heating around the interstitial electrode. Skin surface electrodes (ground pads) are used to complete the electrical circuit. RF ablation has been in use for nearly 20 years, with good results for local tumor control, extended survival and low complication rates1,2. Recent studies suggest RF ablation may be a first-line treatment option for small hepatocellular carcinoma and renal-cell carcinoma3-5. However, RF heating is hampered by local blood flow and high electrical impedance tissues (eg, lung, bone, desiccated or charred tissue)6,7. Microwaves may alleviate some of these problems by producing faster, volumetric heating8-10. To create larger or conformal ablations, multiple microwave antennas can be used simultaneously while RF electrodes require sequential operation, which limits their efficiency. Early experiences with microwave systems suggest efficacy and safety similar to, or better than RF devices11-13.
Alternatively, cryoablation freezes the target tissues to lethal levels (-20 to -40 &deg;C). Percutaneous cryoablation has been shown to be effective against RCC and many metastatic tumors, particularly colorectal cancer, in the liver14-16. Cryoablation may also be associated with less post-procedure pain and faster recovery for some indications17. Cryoablation is often contraindicated for primary liver cancer due to underlying coagulopathy and associated bleeding risks frequently seen in cirrhotic patients. In addition, sudden release of tumor cellular contents when the frozen tissue thaws can lead to a potentially serious condition known as cryoshock 16.
Thermal tumor ablation can be performed at open surgery, laparoscopy or using a percutaneous approach. When performed percutaneously, the ablation procedure relies on imaging for diagnosis, planning, applicator guidance, treatment monitoring and follow-up. Ultrasound is the most popular modality for guidance and treatment monitoring worldwide, but computed tomography (CT) and magnetic resonance imaging (MRI) are commonly used as well. Contrast-enhanced CT or MRI are typically employed for diagnosis and follow-up imaging.

A thermal tumor ablation procedure is described. The entire procedure is detailed, including pretreatment planning and imaging studies, anesthesia, adjuvant techniques to facilitate a percutaneous approach, imaging guidance of the ablation device to the tumor, thermal treatment, post-treatment care and follow-up.

Percutaneous thermal ablation is an emerging treatment option for many tumors of the abdomen not amenable to conventional treatments. During a thermal ...

Creation of Reversible Cholestatic Rat Model

Cholestasis is a clinical condition commonly encountered by both surgeons and gastroenterologists. Cholestasis can cause various physiological changes and affect the nutritional status and surgical outcomes. Study of the pathophysiological changes occurring in the liver and other organs is of importance. Various studies have been done in cholestatic rat models.
We used a reversible cholestatic rat model in our recent study looking at the role of methylprednisolone in the ischemia reperfusion injury. Various techniques for creation of a reversible cholestatic model have been described. Creation of a reversible cholestatic rat model can be challenging in view of the smaller size and unique hepatopancreatobiliary anatomy in rats. This video article demonstrates the creation of a reversible cholestatic model.
This model can be used in various studies, such as looking at the changes in nutritional, physiological, pathological, histological and immunological changes in the gastrointestinal tract. This model can also be used to see the effects of cholestasis and various therapeutic interventions on major hepatic surgeries.

Cholestasis is a clinical condition commonly encountered by both surgeons and gastroenterologists. Creation of a reversible cholestatic rat model can be challenging in view of the smaller size and unique hepatopancreatobiliary anatomy in rats. This video article demonstrates the creation of a reversible cholestatic model.

Cholestasis is a clinical condition commonly encountered by both surgeons and gastroenterologists. Cholestasis can cause various physiological changes and ...

Orthotopic Liver Transplantation in Rats

Clinical progress in the field of liver transplantation has been largely supported by animal models1,2. Since the publication of the first orthotopic rat liver transplantation in 1979 by Kamada et al.3, this model has remained the gold standard despite various proposed alternative techniques4. Nevertheless, its broader use is limited by its steep learning curve5.
In this video paper, we show a simple and easy-to-establish revision of Kamada's two-cuff technique. The suprahepatic vena cava anastomosis is performed manually with a running suture, and the vena porta and infrahepatic vena cava anastomoses are performed utilizing a quick-linker cuff system6. Manufacturing the quick-linker kit is shown in a separate video paper.

We present an easy-to-establish revision of the classical two-cuff technique for orthotopic liver transplantation in rat.

Clinical progress in the field of liver transplantation has been largely supported by animal models1,2. Since the publication of the first orthotopic rat ...

Ascending Aortic Constriction in Rats for Creation of Pressure Overload Cardiac Hypertrophy Model

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart failure. Here, we describe a detailed surgical procedure for creating pressure overload and cardiac hypertrophy in rats by constriction of the ascending aorta using a small metallic clip. After anesthesia, the trachea is intubated by inserting a cannula through a half way incision made between two cartilage rings of trachea. Then a skin incision is made at the level of the second intercostal space on the left chest wall and muscle layers are cleared to locate the ascending portion of aorta. The ascending aorta is constricted to 50&#8211;60% of its original diameter by application of a small sized titanium clip. Following aortic constriction, the second and third ribs are approximated with prolene sutures. The tracheal cannula is removed once spontaneous breathing was re-established. The animal is allowed to recover on the heating pad by gradually lowering anesthesia. The intensity of pressure overload created by constriction of the ascending aorta is determined by recording the pressure gradient using trans-thoracic two dimensional Doppler-echocardiography. Overall this protocol is useful to study the remodeling events and contractile properties of the heart during the gradual onset and progression from compensated cardiac hypertrophy to heart failure stage.

We describe a stepwise procedure for creating pressure overload and left ventricular hypertrophy in Wistar rats by constriction of the ascending aorta using a small metallic clip. This model is extensively used for studying remodeling changes during cardiac hypertrophy and for identifying and evaluating strategies for regression of such changes.

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart ...

Carotid Artery Infusions for Pharmacokinetic and Pharmacodynamic Analysis of Taxanes in Mice

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study model. As the use of mouse models are often a vital step in preclinical drug discovery and drug development1-8, it is necessary to design a system to introduce drugs into mice in a uniform, reproducible manner. Ideally, the system should permit the collection of blood samples at regular intervals over a set time course. The ability to measure drug concentrations by mass-spectrometry, has allowed investigators to follow the changes in plasma drug levels over time in individual mice1, 9, 10. In this study, paclitaxel was introduced into transgenic mice as a continuous arterial infusion over three hours, while blood samples were simultaneously taken by retro-orbital bleeds at set time points. Carotid artery infusions are a potential alternative to jugular vein infusions, when factors such as mammary tumors or other obstructions make jugular infusions impractical. Using this technique, paclitaxel concentrations in plasma and tissue achieved similar levels as compared to jugular infusion. In this tutorial, we will demonstrate how to successfully catheterize the carotid artery by preparing an optimized catheter for the individual mouse model, then show how to insert and secure the catheter into the mouse carotid artery, thread the end of the catheter out through the back of the mouse&#8217;s neck, and hook the mouse to a pump to deliver a controlled rate of drug influx. Multiple low volume retro-orbital bleeds allow for analysis of plasma drug concentrations over time.

This method was developed with the goal of delivering a steady drug solution via the carotid artery, to assess the pharmacokinetics of novel drugs in mouse models.

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study ...

A Model of Cardiac Remodeling Through Constriction of the Abdominal Aorta in Rats

Heart failure is one of the leading causes of death worldwide. It is a complex clinical syndromethat includes fatigue, dyspnea, exercise intolerance, and fluid retention. Changes in myocardial structure, electrical conduction, and energy metabolism develop with heart failure, leading to contractile dysfunction, increased risk of arrhythmias, and sudden death. Hypertensive heart disease is one of the key contributing factors of cardiac remodeling associated with heart failure. The most commonly-used animal model mimicking hypertensive heart disease is created via surgical interventions, such as by narrowing the aorta. Abdominal aortic constriction is a useful experimental technique to induce a pressure overload, which leads to heart failure. The surgery can be easily performed, without the need for chest opening or mechanical ventilation. Abdominal aortic constriction-induced cardiac pathology progresses gradually, making this model relevant to clinical hypertensive heart failure. Cardiac injury and remodeling can be observed 10 weeks after the surgery. The method described here provides a simple and effective approach to produce a hypertensive heart disease animal model that is suitable for studying disease mechanisms and for testing novel therapeutics.

A rat model of abdominal aortic constriction that induces cardiac hypertrophy and remodeling is described. An efficient, highly-reproducible, and minimally-invasive method is used to provide a simple yet useful platform for research in myocardial hypertrophy and dysfunction.

Heart failure is one of the leading causes of death worldwide. It is a complex clinical syndromethat includes fatigue, dyspnea, exercise intolerance, and ...

Creation of a Rodent Model of Abdominal Aortic Aneurysm by Blocking Adventitial Vasa Vasorum Perfusion

The adventitial vasa vasorum (VV) provides oxygen and nourishment to the aortic wall. Hypoxia in the aortic wall can cause enlarged abdominal aortic aneurysms (AAAs). This article introduces and describes a standard protocol used to induce AAAs through adventitial VV hypoperfusion created with a combination of polyurethane catheter insertion into the aortic lumen and suture ligation of the infrarenal abdominal aorta.
The protocol involves the use of male rats weighing 300-400 g, which are provided food and water ad libitum. After laparotomy with a ventral midline abdominal incision, exfoliation of the aorta is performed, which blocks blood flow from the perivascular tissue. Aortotomy involving a small incision adjacent to the renal artery branches is performed, and a polyurethane catheter is inserted using an 18-gauge indwelling needle. After repairing the incision, tight ligation of the aorta over the catheter blocks VV blood flow from the proximal direction through the aortic wall without disturbing the aortic blood flow. This technique can induce an AAA with progressive aortic dilatation.
The greatest benefit of this model is that VV hypoperfusion causes tissue hypoxia and the development of an infrarenal AAA, which has morphological and pathological characteristics similar to those of a human AAA.

Polyurethane catheter insertion into the aortic lumen and suture ligation of the aorta induce chronic hypoxia due to hypoperfusion of the adventitial vasa vasorum. This article describes a novel animal model of abdominal aortic aneurysm (AAA) with characteristics similar to those of AAA in humans.

The adventitial vasa vasorum (VV) provides oxygen and nourishment to the aortic wall. Hypoxia in the aortic wall can cause enlarged abdominal aortic ...

Balloon-based Injury to Induce Myointimal Hyperplasia in the Mouse Abdominal Aorta

The use of animal models is essential for a better understanding of MH, one major cause for arterial stenosis.In this article, we demonstrate a murine balloon denudation model, which is comparable with established vessel injury models in large animals. The aorta denudation model with balloon catheters mimics the clinical setting and leads to comparable pathobiological and physiological changes. Briefly, after performing a horizontal incision in the aorta abdominalis, a balloon catheter will be inserted into the vessel, inflated, and introduced retrogradely. Inflation of the balloon will lead to intima injury and overdistension of the vessel. After removing the catheter, the aortic incision will be closed with single stiches. The model shown in this article is reproducible, easy to perform, and can be established quickly and reliably. It is especially suitable for evaluating expensive experimental therapeutic agents, which can be applied in an economical fashion. By using different knockout-mouse strains, the impact of different genes on MH development can be assessed.

This article demonstrates a murine model to study the development of myointimal hyperplasia (MH) after aortic balloon injury.

The use of animal models is essential for a better understanding of MH, one major cause for arterial stenosis.In this article, we demonstrate a murine ...

Creation of Colonic Anastomosis in Mice

Intestinal anastomoses are commonly performed in both elective and emergent operations. Even so, anastomotic leaks are a highly feared complications of colonic surgeries and can occur in up to 26% of surgical anastomoses, with mortality being up to 39% for patients with such a leak. Currently, there remains a paucity of data detailing the cellular mechanisms of anastomotic healing. Devising preventative strategies and treatment modalities for anastomotic leak could be greatly potentiated by a better understanding of appropriate anastomotic healing.
A murine model is ideal as previous studies have shown that the murine anastomosis is the most clinically similar to the human case as compared with other animal models. We offer an easily reproducible murine model of colonic anastomosis in mice that will allow for further illustration of anastomotic healing.

Anastomotic leak or breakdown after surgery is a major cause of postoperative morbidity and mortality. Our surgery for creating a colonic anastomosis is a reliable and reproducible method for studying the healing mechanisms of anastomoses.

Intestinal anastomoses are commonly performed in both elective and emergent operations. Even so, anastomotic leaks are a highly feared complications of ...