Dr. Khan acknowledges grant support from NIH/NICHD K12HD052892, the Alpha-1 Foundation, the Hillman Foundation, and the Pittsburgh Liver Research Center. Dr. Michalopoulos acknowledges grant support from NIH/NIDDK P01DK096990. We appreciate the excellent and generous technical assistance of Anne Orr. We are also grateful to Dr. David A. Geller for providing access to the Transplant/Rodent Microsurgery lab.

All procedures were conducted in accordance with ethical guidelines of the Institutional Animal Care and Use Committee of the University of Pittsburgh.
1. Basic Techniques and Common Procedures
<ol>
	<li>Autoclave all microsurgical equipment before use.</li>
	<li>To avoid killing the mouse by anesthesia, check its breathing pattern carefully.</li>
	<li>Touch organs and intestines as little as possible to avoid damaging organs and causing bleeding. Press bleeding points with wet cotton swabs or gauze sponges.</li>
	<li>Use wet cotton swabs for gentle manipulation of organs. Wet, non-woven gauze sponges are used in two sizes, 3.5 &#215; 3.5 cm and 6.0 &#215; 6.0 cm. Use the smaller one to retract whole liver. Use the larger one to wrap the small and large intestines.</li>
</ol>
2. Presurgical Preparation
<ol>
	<li>Use male c57/b6 mice, 8-12 weeks of age (when body weight is approximately 20-35 g) for partial bile duct ligation.</li>
	<li>Allow the mice free access to water and food until induction of anesthesia.</li>
</ol>
3. Partial Bile Duct Ligation Operation
<ol>
	<li>Anesthetize the mouse by putting the animal in an induction chamber with a mix of 1.5-2.0% isoflurane and 1 L/min oxygen. Monitor the animal carefully by observing the respiration rate. When the respiration rate of the animal is one breath per second, the mouse is well-anesthetized.&#160;Since front limb withdrawal reflex disappears more rapidly, pinch the hind limb foot as well to confirm complete absence of the withdrawal reflex.&#160;Eyes should be lubricated with an ophthalmic lubricating agent to prevent corneal ulcers.&#160;Note that first dose of analgesic can be given pre-operatively to prevent stimulation of pain receptors.</li>
	<li>Shave the abdominal wall with hair clippers, and place the mouse on the surgical table under the surgical microscope. Fix all limbs to the table with tape. Use isoflurane inhalation to maintain the mouse under general anesthesia.
	<ol>
		<li>Adjust the isoflurane vaporizer and use 2.0-3.0% isoflurane for induction.</li>
	</ol>
	</li>
	<li>Using sterile swabs, disinfect the abdominal wall first with 0.3-0.5 mL povidone-iodine applied topically, followed by 70% ethanol.&#160;Animal should be covered with a sterile drape.</li>
	<li>Make a long midline abdominal incision from the xiphoid to the pubis using the scissors and Adson Forceps. After making the abdominal incision, reduce isoflurane to 0.8-1.0% for maintenance.</li>
	<li>Expose the abdominal cavity by using a Micro-retractor. Hold the xiphoid with mosquito forceps and retract toward the head of the mouse. Fix the mosquito forceps in place using soft clay.</li>
	<li>Instill 1-2 mL of warmed (37 &#176;C) sterilized phosphate-buffered saline (PBS) into the abdominal cavity to avoid injuring abdominal organs. Hold the small intestines with wet cotton swabs and gently retract them toward the head of the mouse. Cut the ligaments between the small intestines and the retroperitoneum to avoid injuring the small intestines (Figure 1A).</li>
	<li>Wrap the small and large intestines with a wet, non-woven gauze sponge. Place them on the caudal side of the abdominal cavity.&#160;Intestines wrapped in sterile gauze can be placed on the sterile draped field to avoid contamination.</li>
	<li>Gently retract the whole liver toward the xiphoid by using a small wet non-woven gauze sponge to expose the hepatic hilum and hepato-duodenal ligament (Figure 1B).</li>
	<li>Check to confirm the anatomy of the hepatic hilum. The common bile duct is located on ventral side of the portal vein. Confirm locations of the right and the left hepatic bile duct, which drain into the main biliary confluence at the hepatic hilum.</li>
	<li>Identify the left hepatic bile duct which drains the left lobe, and encircle it with a 10-0 nylon suture using the blunt side of a suture needle (Figure 2A). Avoid injuring the portal vein, hepatic artery, and liver surface.</li>
	<li>Ligate the left bile duct with 10-0 nylon. (Figure 2B).</li>
	<li>Place the small and large intestines in the same position as before the operation by using wet cotton swabs.</li>
	<li>Confirm there is no intestinal torsion and intra-abdominal bleeding, then close the muscle and the skin in two layers with 4-0 vicryl.&#160;Braided suture (Vicryl) was used for skin closure, but monofilament is preferred to reduce likelihood of infection. 
	NOTE: Close fascia by continued suture from xiphoid to pubis, and close the skin by continued suture from pubis to xiphoid.</li>
	<li>Stop anesthesia after closing the incision.</li>
</ol>
4. Postoperative Treatment and Follow-Up
<ol>
	<li>Just after the surgery, pinch the dorsal skin of the mouse and inject Buprenex (0.1 mg/kg) and Cefazolin (100 mg/kg) subcutaneously, followed by Buprenex injection every 12 h for 3 days, and Cefazolin every 24 h for 3 days respectively11,12,13.&#160;Note that first dose of analgesic can be given pre-operatively to prevent stimulation of pain receptors. Cefazolin and other peri-operative antibiotics are only necessary for immune-suppressed animals, such as those used in transplantation studies. 
	&#8203;NOTE: If the surgery is successfully performed, the mouse usually recovers within 30 min. Activity of the mice will be almost the same as the preoperative condition.</li>
	<li>Check the mice daily for any signs of distress.
	<ol>
		<li>Sacrifice the mice by the cervical dislocation under general anesthesia to procure livers and other tissue samples at defined time points (i.e., 7, 14, 21 days) after pBDL.</li>
	</ol>
	</li>
</ol>

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J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prolonged+bile+duct+obstruction:+a+new+experimental+model+for+cirrhosis+in+the+rat.">Prolonged bile duct obstruction: a new experimental model for cirrhosis in the rat.</a> Br J Exp Pathol. 65 (3), 305-311 (1984).</li><li>Michalopoulos, G. K., Barua, L., Bowen, W. 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Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toxicology+of+cefazolin+in+animals.">Toxicology of cefazolin in animals.</a> J Infect Dis. 128, 378 (1973).</li><li>Kunst, M. W., Mattie, H., van Furth, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibacterial+efficacy+of+cefazolin+and+cephradine+in+neutropenic+mice.">Antibacterial efficacy of cefazolin and cephradine in neutropenic mice.</a> Infection. 7 (1), 30-34 (1979).</li><li>Traul, K. A., 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=Safety+studies+of+post-surgical+buprenorphine+therapy+for+mice.">Safety studies of post-surgical buprenorphine therapy for mice.</a> Lab Anim. 49 (2), 100-110 (2015).</li><li>Carlson, J. A., 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=Accumulation+of+PiZ+alpha+1-antitrypsin+causes+liver+damage+in+transgenic+mice.">Accumulation of PiZ alpha 1-antitrypsin causes liver damage in transgenic mice.</a> J Clin Invest. 83 (4), 1183-1190 (1989).</li><li>Sifers, R. N., Finegold, M. J., Woo, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alpha-1-antitrypsin+deficiency:+accumulation+or+degradation+of+mutant+variants+within+the+hepatic+endoplasmic+reticulum.">Alpha-1-antitrypsin deficiency: accumulation or degradation of mutant variants within the hepatic endoplasmic reticulum.</a> Am J Respir Cell Mol Biol. 1 (5), 341-345 (1989).</li><li>Rudnick, D. A., Shikapwashya, O., Blomenkamp, K., Teckman, J. 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The authors have no disclosures.

Although cBDL is the most common experimental technique for obstructive cholestasis, it can present multiple challenges in rodents. Depending on the number of post-operative days required to achieve an endpoint, the animals can experience significant morbidity and mortality as time progresses. The degree of tissue injury and biliary necrosis is further exacerbated when working with some transgenic mouse models of liver disease, which demonstrate abnormal liver parenchyma and function at baseline. Compared to cBDL, report...

Surgical models of acute liver injury and repair, such as partial hepatectomy or common bile duct ligation (cBDL), have been used for decades in rodents to study liver regeneration and pathobiology1,2. In cBDL, the common bile duct (which drains all bile produced in the liver) is ligated, resulting in obstructive cholestasis, inflammation, and fibrosis in the first 2-3 weeks following surgery, with eventual progression to cirrhosis3. Bile duct proliferation, transdifferentiation, and induction of resident liver progenitor cells are also features of cBDL4,5. Although cBDL elucidates specific mechanisms of obstructive cholangiopathy, which are well-characterized with reproducible outcomes in wild-type mice and in those strains with normal livers6,7,8, the procedure can be technically demanding in some transgenic mouse models of liver diseases, requiring more animals than anticipated due to the higher morbidity and mortality of biliary obstruction over time. This technique is also beneficial for studying transgenic mice with underlying liver disease, which might not otherwise tolerate the stress of prolonged time course experiments following cBDL.
pBDL can provide a reasonable alternative to help overcome some of these challenges. Initial pBDL studies in wild-type mice aimed to distinguish locally acting and systemic mediators of inflammation9. In pBDL, the main biliary confluence of the right and left hepatic bile ducts above the common bile duct is carefully visualized at the hilum, and only the left hepatic bile duct is ligated to generate a localized obstructive cholestasis. pBDL offers several advantages to cBDL. In pBDL, the unligated right lobe serves as an identically matched internal control for the ligated left lobe, subjected to the same systemic effects, such as nutritional status or circulating factors. Although systemic pro-inflammatory mediators were present, Osawa et al. observed less fibrosis and necrosis in the unligated lobes, but increased inflammatory cells and transforming growth factor-&#946; expression in the ligated lobe9.
More recently, pBDL has been redefined to study liver parenchymal effects of retained bile10. By using the same animal for internal control (unligated &#34;sham&#34;) and experimental groups, pBDL effectively halves the number of animals needed per experiment, which in turn is more cost-effective. The mice tolerate the effects of pBDL much better, so that the ideal time course experiment (&#8805;2 weeks) can be achieved in the ligated lobe. Most importantly, pBDL can distinguish direct intrahepatic effects of obstructive cholestasis and retained bile components in the ligated lobe, compared to the unligated control lobe. Overall, pBDL is an attractive method to study lobe-specific effects of localized cholestasis in the liver.

<table><tbody><tr><td>Microscope-Leica Wild M650, 6&amp;ndash;40&amp;times; magnification</td><td>Leica Microsystems</td><td>n/a</td><td></td></tr><tr><td>Tec 3 isoflurane funnel fill vaporizer</td><td>General Anesthetic Services</td><td>n/a</td><td></td></tr><tr><td>Stevens Tenotomy Scissors</td><td>Accurate Surgical &amp;amp; Scientific Instruments Corporation</td><td>ASSI.9193</td><td></td></tr><tr><td>Adson Forceps</td><td>Fine science tools</td><td>11006-12</td><td></td></tr><tr><td>Mosquito classic delicate hemostatic forceps</td><td>Codman</td><td>30-4472</td><td></td></tr><tr><td>Micro-retractor</td><td>Murdock; Roboz Surgical Instrument</td><td>RS-6550</td><td></td></tr><tr><td>Nonwoven gauze sponges</td><td>Fisherband</td><td>870-PC-DBL</td><td></td></tr><tr><td>Puritan 6&amp;rdquo; Small Cotton Swab w/Wooden Handle</td><td>Puritan Medical Products Company</td><td>868-WCS</td><td></td></tr><tr><td>Dumont SS Forceps - Standard Tips/Straight/Inox/13.5cm</td><td>Fine science tools</td><td>11203-23</td><td></td></tr><tr><td>Dumont SS Forceps - Standard Tips/Angled 45&amp;deg;/Inox/13.5cm</td><td>Fine science tools</td><td>11203-25</td><td></td></tr><tr><td>Vannas Spring Scissors - 3mm Cutting Edge</td><td>Fine science tools</td><td>15000-00</td><td></td></tr><tr><td>Microneedle holder</td><td>Aesculap Surgical Instruments</td><td>FD231R</td><td></td></tr><tr><td>Micro AROSuture, sterile 10-0 nylon suture, 70 &amp;micro;m, TAP points</td><td>AROSurgical Instruments Corporation</td><td>T4A10N07</td><td></td></tr><tr><td>4-0 Vicryl</td><td>Ethicon</td><td>J662H</td><td></td></tr><tr><td>5-ml Syringe</td><td>BD</td><td>309646</td><td></td></tr><tr><td>Falcon tissue culture dish, 60 &amp;times; 15 mm</td><td>Corning</td><td>353002</td><td></td></tr><tr><td>Isoflurane, United States Pharmacopeia (USP) liquid for inhalation, 250 ml</td><td>Piramal Healthcare</td><td>NDC 66794-017-25</td><td></td></tr><tr><td>Buprenex injectable (buprenorphine hydrochloride)</td><td>Reckitt Benckiser Pharmaceuticals</td><td>NDC 12496-0757-1</td><td></td></tr><tr><td>Cefazolin for injection , USP</td><td>APP Pharmaceuticals</td><td>NDC 63323-238-61</td><td></td></tr><tr><td>PVP scrub solution (povidone&amp;ndash;iodine 7.5%)</td><td>Medline</td><td>NDC 12496-0757-1</td><td></td></tr><tr><td>70% Ethanol</td><td>Decon Labs</td><td>2716</td><td></td></tr><tr><td>Phosphate Buffered Saline Without Calcium or Magnesium</td><td>LONZA</td><td>17-516F</td><td></td></tr><tr><td>Sirius Red</td><td>Sigma</td><td>365548</td><td></td></tr><tr><td>Hematolxylin</td><td>Fisher (Richard-Allan Scientific)</td><td>22-050-111 (7211)</td><td></td></tr><tr><td>Eosin</td><td>Anatech (Fisher)</td><td>832 (NC9686037)</td><td></td></tr><tr><td>Formalin</td><td>Fisher</td><td>SF100-20</td><td></td></tr></tbody></table>

partial bile duct ligation in the mouse: a controlled model of localized obstructive cholestasis

In rodents, complete bile duct ligation (cBDL) of the common bile duct is an established surgical technique for studying obstructive cholestasis and bile duct proliferation. However, long-term experiments can lead to increased morbidity and mortality. In select mouse strains with underlying liver disease, meaningful comparisons can be made even with ligation of a single lobe of the liver, which can reduce animal losses and expenses. Here, we describe partial bile duct ligation (pBDL) in the mouse, in which only the left hepatic bile duct is ligated, causing biliary obstruction in the left lobe but not the remaining lobes. With careful microsurgical technique, pBDL experiments can be cost-effective, since the unligated lobe serves as an internal control to the ligated lobes, when subjected to the same conditions in the same animal. Unlike cBDL, a separate sham-operated control group is not necessary. pBDL is highly useful to directly compare localized versus systemic effects of cholestasis and other retained bile components. pBDL can also be repurposed as a novel method to investigate mechanisms related to medications and cell migration.

For this typical experiment, pBDL was performed in triplicate PiZ transgenic mice, which recapitulate the human liver disease found in alpha-1 antitrypsin (A1AT) deficiency. The PiZ mouse overexpresses a transgene consisting of multiple genomic fragments of DNA that contain the coding regions of the mutant human A1AT gene and promoter, together with introns and ~2 kilobases of upstream and downstream flanking regions14,15. Normal ...

Watch this Scientific Journal Video about Partial Bile Duct Ligation in the Mouse: A Controlled Model of Localized Obstructive Cholestasis at JoVE.com

Partial Bile Duct Ligation in the Mouse: A Controlled Model of Localized Obstructive Cholestasis

Here, we present partial bile duct ligation as a surgical model of liver injury and regeneration in rodents.

In rodents, complete bile duct ligation (cBDL) of the common bile duct is an established surgical technique for studying obstructive cholestasis and bile ...

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Biology

15.5K Views.  Jichi Medical University. Hier presenteren we gedeeltelijke gal duct afbinding als een chirurgische model van lever schade en regeneratie van knaagdieren.

Video: Partial Bile Duct Ligation in the Mouse: A Controlled Model of Localized Obstructive Cholestasis

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 ...

Medicine

Determining Bile Duct Density in the Mouse Liver

Mouse is broadly used as a model organism to study biliary diseases. To evaluate the development and function of the biliary system, various techniques are used, including serum chemistry, histological analysis, and immunostaining for specific markers. Although these techniques can provide important information about the biliary system, they often do not present a full picture of bile duct (BD) developmental defects across the whole liver. This is in part due to the robust ability of the mouse liver to drain the bile even in animals with significant impairment in biliary development. Here we present a simple method to calculate the average number of BDs associated with each portal vein (PV) in sections covering all lobes of mutant/transgenic mice. In this method, livers are mounted and sectioned in a stereotypic manner to facilitate comparison among various genotypes and experimental conditions. BDs are identified via light microscopy of cytokeratin-stained cholangiocytes, and then counted and divided by the total number of PVs present in liver section. As an example, we show how this method can clearly distinguish between wild-type mice and a mouse model of Alagille syndrome. The method presented here cannot substitute for techniques that visualize the three-dimensional structure of the biliary tree. However, it offers an easy and direct way to quantitatively assess BD development and the degree of ductular reaction formation in mice.

We present a rather simple and sensitive method for accurate quantification of bile duct density in the mouse liver. This method can aid in determining the effects of genetic and environmental modifiers and the effectiveness of potential therapies in mouse models of biliary diseases.

Mouse is broadly used as a model organism to study biliary diseases. To evaluate the development and function of the biliary system, various techniques ...

Developmental Biology

Bile Duct Ligation in Mice: Induction of Inflammatory Liver Injury and Fibrosis by Obstructive Cholestasis

In most vertebrates, the liver produces bile that is necessary to emulsify absorbed fats and enable the digestion of lipids in the small intestine as well as to excrete bilirubin and other metabolic products. In the liver, the experimental obstruction of the extrahepatic biliary system initiates a complex cascade of pathological events that leads to cholestasis and inflammation resulting in a strong fibrotic reaction originating from the periportal fields. Therefore, surgical ligation of the common bile duct has become the most commonly used model to induce obstructive cholestatic injury in rodents and to study the molecular and cellular events that underlie these pathophysiological mechanisms induced by inappropriate bile flow. In recent years, different surgical techniques have been described that either allow reconnection or reanastomosis after bile duct ligation (BDL), e.g., partial BDL, or other microsurgical methods for specific research questions. However, the most frequently used model is the complete obstruction of the common bile duct that induces a strong fibrotic response after 21 to 28 days. The mortality rate can be high due to infectious complications or technical inaccuracies. Here we provide a detailed surgical procedure for the BDL model in mice that induce a highly reproducible fibrotic response in accordance to the 3R rule for animal welfare postulated by Russel and Burch in 1959.

Disruption of bile flow results in severe inflammatory cholestatic liver injury with a characteristic time-dependent sequence of morphological alterations. Here we present a protocol for the surgical ligation of the common bile duct in mice that allows to induce a strong fibrotic response after 21 to 28 days.

In most vertebrates, the liver produces bile that is necessary to emulsify absorbed fats and enable the digestion of lipids in the small intestine as well ...

A Silver Nanoparticle Method for Ameliorating Biliary Atresia Syndrome in Mice

Biliary atresia (BA) is a severe type of cholangitis with high mortality in children of which the etiology is still not fully understood. Viral infections may be one possible cause. The typical animal model used for studying BA is established by inoculating a neonatal mouse with a rhesus rotavirus. Silver nanoparticles have been shown to exert antibacterial and antiviral effects; their function in the BA mouse model is evaluated in this study. Currently, in BA animal experiments, the methods used to improve the symptoms of BA mice are generally symptomatic treatments given via food or other drugs. The aim of this study is to demonstrate a new method for ameliorating BA syndrome in mice by the intraperitoneal injection of silver nanoparticles and to provide detailed methods for preparing the silver nanoparticle gel formulation. This method is simple and widely applicable and can be used to research the mechanism of BA, as well as in clinical treatments. Based on the BA mouse model, when the mice exhibit jaundice, the prepared silver nanoparticle gel is injected intraperitoneally to the surface of the lower liver. The survival status is observed, and biochemical indicators and liver histopathology are examined. This method allows a more intuitive understanding of both the establishment of the BA model and novel BA treatments.

This article describes in detail a method based on silver nanoparticles for ameliorating biliary atresia syndrome in an experimental biliary atresia mouse model. A solid understanding of the reagent preparation process and the neonatal mouse injection technique will help familiarize researchers with the method used in neonatal mouse model studies.

Biliary atresia (BA) is a severe type of cholangitis with high mortality in children of which the etiology is still not fully understood. Viral infections ...

Immunology and Infection

A Mouse Model of Chronic Liver Fibrosis for the Study of Biliary Atresia

Biliary atresia (BA) is a fatal disease involving obstructive jaundice, and it is the most common indication for liver transplantation in children. Due to the complex etiology and unknown pathogenesis, there are still no effective drug treatments. At present, the classic BA mouse model induced by rhesus rotavirus (RRV) is the most commonly used model for studying the pathogenesis of BA. This model is characterized by growth retardation, jaundice of the skin and mucosa, clay stools, and dark yellow urine. The histopathology shows severe liver inflammation and obstruction of the intrahepatic and extrahepatic bile ducts, which are similar to the symptoms of human BA. However, the livers of end-stage mice in this model lack fibrosis and cannot fully simulate the characteristics of liver fibrosis in clinical BA. The presented study developed a novel BA mouse model of chronic liver fibrosis by injecting 5-10 &#181;g of anti-Ly6G antibody four times, with gaps of 2 days after each injection. The results showed that some of the mice successfully formed chronic BA with typical fibrosis after the time lapse, meaning these mice represent a suitable animal model for the virus-induced liver fibrosis mechanistic study of BA and a platform for developing future BA treatments.

We established a mouse model of chronic liver fibrosis, which provides a suitable animal model for the virus-induced liver fibrosis mechanistic study of biliary atresia (BA) and a platform for future BA treatments.

Biliary atresia (BA) is a fatal disease involving obstructive jaundice, and it is the most common indication for liver transplantation in children. Due to ...

A Mouse Model for Chronic Pancreatitis via Bile Duct TNBS Infusion

Chronic pancreatitis (CP) is a complex disease involving pancreatic inflammation and fibrosis, glandular atrophy, abdominal pain and other symptoms. Several rodent models have been developed to study CP, of which the bile duct 2,4,6 -trinitrobenzene sulfonic acid (TNBS) infusion model replicates the features of neuropathic pain seen in CP. However, bile duct drug infusion in mice is technically challenging. This protocol demonstrates the procedure of bile duct TNBS infusion for generation of a CP mouse model. TNBS was infused into the pancreas through the ampulla of Vater in the duodenum. This protocol optimized drug volume, surgical techniques, and drug handling during the procedure. TNBS-treated mice showed features of CP as reflected by bodyweight and pancreas weight reductions, changes in pain-associated behaviors, and abnormal pancreatic morphology. With these improvements, mortality associated with TNBS injection was minimal. This procedure is not only critical in generating pancreatic disease models but is also useful in local pancreatic drug delivery.

Chronic pancreatitis (CP) is a disease characterized by inflammation and fibrosis of the pancreas, often associated with intractable abdominal pain. This article focuses on refining the technique to generate a mouse model of CP via bile duct infusion with 2,4,6 -trinitrobenzene sulfonic acid (TNBS).

Chronic pancreatitis (CP) is a complex disease involving pancreatic inflammation and fibrosis, glandular atrophy, abdominal pain and other symptoms. ...

Extrahepatic Bile Duct and Gall Bladder Dissection in Nine-Day-Old Mouse Neonates

The dissection of murine neonatal bile ducts has been described as difficult. The main aim of the described standard operating procedure is the isolation of the extrahepatic bile duct (EBD) in mouse neonates without damaging the bile duct during preparation. Because of its exceptionally close preparation compared to the cholangiocytes cell line and harvesting of the entire extrahepatic bile duct system (EBDS), the described approach is extremely useful in researching animal models of newborn bile duct disorders, such as biliary atresia. After euthanasia, the peritoneal cavity was accessed, and the bile duct system, duodenum, and liver were extracted with the unique En-bloc-Resection (EbR). The extracted sample is placed on a foam mat, and the EBD is dissected from contaminating cells atraumatically without necessary touch. The dissection of the entire EBDS is a significant advantage of this method. Caution must be taken due to the small size and amount of bile duct tissue. Using the described technique, there is no damage to the cholangiocytes. Further, the purity of the technique is reproducible (n = 10). Therefore, optimally comparable samples can be harvested. Furthermore, no bile duct tissue is harmed, because any contact with the bile duct system can be avoided during preparation, leaving the bile fluid inside the gall bladder. Most importantly, while performing the final gall bladder and bile duct dissection, atraumatic microinstruments were used only slightly lateral of the bile duct without squeezing it. This is the key to a clean and intact sample, and essential for further histological investigation or the isolation of cholangiocytes. To summarize, the described innovative dissection technique enables especially inexperienced operators with the necessary equipment to isolate the EBDS as cleanly as possible.

For the observation of murine neonatal bile duct disorders, an intact bile duct and efficient preparation are required. Therefore, a new approach for isolating the entire extrahepatic bile duct system in murine neonates was successfully developed while maintaining the integrity of the bile duct.

The dissection of murine neonatal bile ducts has been described as difficult. The main aim of the described standard operating procedure is the isolation ...

Studying Liver Regeneration of ALLPS in Animal Models for Staged Hepatectomy

A Mouse Model of the Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy Procedure Aided by Microscopy

Hepatectomy is widely regarded as the primary treatment for hepatic malignancies; yet, postoperative liver failure remains a major cause of perioperative mortality, severely impacting patient outcomes. In a robust hepatic environment, the future liver remnant (FLR) must exceed 25%, and in cases of cirrhosis, this requirement increases to over 40%. The inadequacy of FLR is currently a major obstacle in the progression of hepatic surgery.
Traditional methods to enhance FLR hypertrophy mainly focus on portal vein embolization (PVE), but its effectiveness is considerably limited. In recent years, there have been numerous reports on a novel biphasic hepatectomy method involving hepatic partitioning and portal vein ligation, known as associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). ALPPS surpasses PVE in efficiently and considerably inducing FLR hypertrophy. However, the detailed mechanisms driving ALPPS-facilitated hepatic regeneration are not fully understood. Thus, replicating ALPPS in animal models is crucial to thoroughly investigate the molecular mechanisms of hepatic regeneration, offering valuable theoretical and practical insights.

Author Spotlight: Advancing Liver Regeneration Research through ALPPS Mouse Model

Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS) has been shown to result in remarkable liver regeneration after several weeks post first-stage surgery. Animal models that have undergone ALPPS have been developed to explore potential liver regeneration ability and achieve favorable clinical outcomes.

Hepatectomy is widely regarded as the primary treatment for hepatic malignancies; yet, postoperative liver failure remains a major cause of perioperative ...

Mouse Extended Hepatectomy Model for Liver Regeneration Studies

Extended 78&#37; Hepatectomy in a Mouse Surgical Model

Partial 2/3 hepatectomy in mice is used in research to study the liver's regenerative capacity and explore outcomes of liver resection in a number of disease models. In the classical partial 2/3 hepatectomy in mice, two of the five liver lobes, namely the left and median lobes representing approximately 66% of the liver mass, are resected en bloc with an expected postoperative survival of 100%. More aggressive partial hepatectomies are technically more challenging and hence, have seldom been used in mice. Our group has developed a mouse model of an extended hepatectomy technique in which three of the five liver lobes, including the left, median, and right upper lobes, are resected separately to remove approximately 78% of the total liver mass. This extended resection, in otherwise healthy mice, leaves a remnant liver that cannot always sustain adequate and timely regeneration. Failure to regenerate ultimately results in 50% postoperative lethality within 1 week due to fulminant hepatic failure. This procedure of extended 78% hepatectomy in mice represents a unique surgical model for the study of small-for-size syndrome and the evaluation of therapeutic strategies to improve liver regeneration and outcomes in the setting of liver transplantation or extended liver resection for cancer.

Author Spotlight: Evaluating Therapeutic Strategies to Enhance Liver Regeneration

The mouse model of partial 2/3 (66%) hepatectomy is well described in the literature, but more extended hepatectomies mimicking small-for-size syndrome after liver transplantation have seldom been used. We describe an extended 78% hepatectomy procedure in a mouse model that results in approximately 50% postoperative lethality in healthy mice.

Partial 2/3 hepatectomy in mice is used in research to study the liver's regenerative capacity and explore outcomes of liver resection in a number of ...

Isolation and Culture of Primary Cholangiocytes from Mice with Polycystic Liver Disease Using a Two-step Digestion Method

In this protocol, we optimized a two-step digestion method to isolate high-purity and high-viability primary cholangiocytes from wild-type mice and mice with polycystic liver disease (PLD). After anesthetizing the mice, the livers were perfused through the inferior vena cava with 50 mL of Solution A, followed by 30 mL of Solution B at 37 &#176;C to enzymatically digest the liver tissue. Mechanical dissociation, shaking, and microdissection were performed to remove adherent parenchymal cells, leaving an intact biliary tree. The biliary tree was then finely minced and digested with shaking for 60 min at 37 &#176;C. The resulting single-cell suspension was collected using a 70 &#181;m cell strainer. Cholangiocytes were purified using immunomagnetic isolation. The cell suspension was incubated with an anti-EpCAM antibody under rotation for 45 min at 4 &#176;C, followed by the addition of Protein G beads and further rotation for another 45 min at 4 &#176;C. After three washes with PBS, the cholangiocytes were collected using a magnetic separator. The purified primary cholangiocytes were resuspended in Cholangiocyte Culture Medium and seeded onto cell culture dishes coated with 1 mg/mL type I rat tail collagen. The purity of the cholangiocytes was confirmed by immunostaining for the cholangiocyte-specific marker cytokeratin-19 (CK19). Although this study focused on isolating primary cholangiocytes from wild-type and PLD mice, we are confident that the protocol can be applied to other disease mouse models as well. This detailed two-step digestion method facilitates in vitro studies of cholangiopathies and the development of targeted therapies.

This protocol describes an optimized two-step digestion method for isolating high-purity and high-viability primary cholangiocytes from wild-type mice and mice with polycystic liver disease.

In this protocol, we optimized a two-step digestion method to isolate high-purity and high-viability primary cholangiocytes from wild-type mice and mice ...

Partial Bile Duct Ligation in the Mouse: A Controlled Model of Localized Obstructive Cholestasis

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