This work was supported by grants from the Ministry of Education Innovation Team Development Program of China (No. IRT16R57), National Natural Science Foundation of China (No. 81470896), and a research fund for Young Talent Recruiting Plans of Xi'an Jiaotong University (RW).

The protocol was carried out in accordance with the Guidelines for the Care and Use of Laboratory Animals and was approved by the Committee on the Ethics of Animal Experiments of Xi&#39;an Jiaotong University, Xi&#39;an, Shaanxi Province, China.
NOTE: None of the procedures in this protocol was performed under a surgical microscope.
1. Preoperative Preparation
<ol>
	<li>The Design and Shape of the Magnetic Rings (Figure 1)
	<ol>
		<li>Assemble the magnetic anastomosis device by matching a pair of neodymium-iron-boron magnetic rings.</li>
		<li>Design the rings according to the parameters of rat SHVC with a major axis diameter, minor axis diameter, thickness and weight of 8 mm, 5.5 mm, 1 mm, 0.5 g, respectively.</li>
		<li>Curve the rings to the desired shape by a wire-electrode cutting technique, and then coat the obtained rings with a titanium oxide airbrush and sterilize with 500 mg/L ethylene oxide at 55-60 &#176;C for 6 h.</li>
	</ol>
	</li>
	<li>The cuffs (Figure 2)
	<ol>
		<li>Prepare the cuff for anastomosis of the IHVC and PV by cutting the polyethylene tube. Ensure that the cuff body is 5 mm long with a 2 mm cuff extension. 
		NOTE: The inner and outer diameters of the PV cuff are 1.8 and 2.1 mm, while those of the IHVC cuff are 2.6 and 2.8 mm, respectively.</li>
	</ol>
	</li>
	<li>The Stent (Figure 2)
	<ol>
		<li>Prepare the stent for anastomosis of the BD by cutting 24-G intravenous cannula with a length of 5 mm to produce slant at both ends.</li>
	</ol>
	</li>
	<li>Experimental Animals
	<ol>
		<li>Use male Sprague Dawley rats weighing between 250 and 280 g as donors and recipients. Ensure that the recipient is the same weight or slightly heavier (&#60; 10 g) than the donor.</li>
		<li>Keep the rats in climate-controlled rooms with free access to food and water before surgery.</li>
	</ol>
	</li>
</ol>
2. Donor Operation
<ol>
	<li>Inject buprenorphine (0.05 mg/kg) subcutaneously as an analgesic 1 hour before operation.</li>
	<li>Anesthetize the donor rat by isoflurane inhalation. Use 5 vol% isoflurane at a flow rate of 1.5 L/min in a Plexiglas box for the induction of anesthesia and 2 vol% isoflurane at a flow rate 0.6-0.8 L/min on a cone mask for the maintenance of anesthesia. Confirm depth of anesthesia by performing a toe pinch and a skin pinch.</li>
	<li>Shave the entire abdominal skin of the rat using an electric shaver to allow for cleaner exposure. Disinfect the corresponding skin with a povidone-iodine solution.</li>
	<li>Open the abdominal cavity via a cruciform incision using surgical scissors from the root of the penis extending to 1 cm above the xiphisternum along linea alba, extending from the midpoint of the longitudinal incision to the midaxillary line. Exteriorize the gastrointestinal tract to the left and cover it with wet gauze.</li>
	<li>Clamp and pull the xiphisternum toward the head using a hemostatic forceps. Dissect the falciform ligament and the connective tissues around the liver. Isolate and ligate the left inferior phrenic vein with a 6-0 silk suture.</li>
	<li>Insert the stent into the bile duct.
	<ol>
		<li>Clamp the BD just above the point where the gastroduodenal vein joins the portal vein and pull it to maintain a little tension using a microforceps. Then perform a &#34;V&#34; incision of 1 mm length on the anterior wall about 5 mm proximal to the biliary confluence by a micro scissors.</li>
		<li>Insert the stent into the lumen of the bile duct using a curved microforceps. Make sure at least a half of the stent lies outside the bile duct.</li>
		<li>Secure the stent with a 6-0 silk suture. Cut one end of the suture. Keep the other one to hold during later anastomosis. Transect the bile duct below the stent and make sure the bile can come out of the stent.</li>
	</ol>
	</li>
	<li>Isolate the IHVC down to the left renal vein level. Free the IHVC from anterior and lateral surrounding tissues by cotton bud dissection until the IHVC is skeletonized. Separate and ligate the right suprarenal vein and the right renal vein with a 6-0 silk suture.</li>
	<li>Heparinize the rat by injecting 50 U of heparin diluted in 2 mL of normal saline solution through the dorsal vein of the penis.</li>
	<li>Perfuse the liver.
	<ol>
		<li>Isolate the abdominal aorta below the left renal vein. Insert a 22-G catheter into the aorta.</li>
		<li>Perform a thoracotomy, clamp the thoracic aorta using a microforceps.</li>
		<li>Perfuse the donor liver through the catheter in the aorta with 20 mL of normal saline solution containing 25 U of heparin (4 &#176;C) at the rate of 3 mL/min with an infusion pump. In the meantime, cut the vena cava below the right renal vein&#160;to allow the perfusion solution to flow out of the liver.</li>
		<li>Transect the SHVC along with part of the diaphragm and IHVC at the level of the left renal vein when the donor liver became pallid.</li>
	</ol>
	</li>
	<li>Dissect the connective tissue surrounding the PV by two micro forceps. Ligate and divide the pyloric veins with an 8-0 prolene suture. Transect the PV at the level of the splenic vein. Excise the donor liver and rinse it with cold normal saline solution. Place it in a cold saline bath 4 &#176;C.</li>
</ol>
3. Graft Preparation
NOTE: All procedures for the liver graft preparation are performed in a cold saline bath at 4 &#176;C.
<ol>
	<li>Attach a cuff to the donor&#39;s IHVC (Figure 3).
	<ol>
		<li>Insert the IHVC into its cuff with the cuff extension pointing towards the liver. Position the cuff extension on the posterior wall of IHVC. Fix the cuff extension and the IHVC with a curved microforceps itself attached using a file clip to the bath container.</li>
		<li>Evert the distal end of the IHVC over the cuff body using two micro forceps.</li>
		<li>Secure the edge with a 6-0 silk suture. Make sure the IHVC is not twisted during the process.</li>
	</ol>
	</li>
	<li>Repeat step 3.1 on the PV to attach a cuff to the donor&#39;s PV.</li>
	<li>Attach a magnetic ring to the donor&#39;s SHVC (Figure 4).
	<ol>
		<li>Pull the diaphragm through the four forceps and trim the SHVC.</li>
		<li>Pass the SHVC through the magnetic ring using the titanium-alloy micro forceps.</li>
		<li>Evert the distal end of the SHVC over the ring.</li>
		<li>Secure the ring with a 6-0 silk suture. Make sure the SHVC is not twisted during the process.</li>
		<li>Remove the excess diaphragm around the liver.</li>
	</ol>
	</li>
	<li>Immerse the donor liver in a cold normal saline bath and store at 4 &#176;C.</li>
</ol>
4. Recipient Operation
NOTE: The schema of the graft implantation in the recipient rat is shown in Figure 5.
<ol>
	<li>Inject buprenorphine (0.05 mg/kg) subcutaneously as an analgesic 1 hour before operation. Anesthetize the donor rat by isoflurane inhalation. Use 5 vol% isoflurane at a flow rate of 1.5 L/min in a Plexiglas box for the induction of anesthesia and 2 vol% isoflurane at a flow rate 0.6-0.8 L/min on a cone mask for the maintenance of anesthesia.</li>
	<li>Shave the entire abdominal skin of the rat. Disinfect the corresponding skin with a povidone-iodine solution.</li>
	<li>Open the abdominal cavity via a 4 cm midline incision. Place the abdominal retractors. Pull the ribs as far apart as possible from the midline.</li>
	<li>Clamp and pull the xiphisternum toward the head using a hemostatic forceps. Dissect the connective tissues and ligaments around the liver. Ligate and divide the hepato-esophageal ligament. Ligate and divide the hepatic artery with an 8-0 prolene suture.</li>
	<li>Isolate the common bile duct from the first hepatic portal. Place a 6-0 silk suture around the common bile duct just below its division and ligate the common bile duct.</li>
	<li>Dissect the IHVC down to the right renal vein. Ligate and divide the right adrenal vein. Place a strap in the SHVC of the liver.</li>
	<li>Clamp the IHVC just above the right renal vein with microvessel clips. Clamp the PV at the level of the pyloric vein with microvessel clips.
	<ol>
		<li>To flush the blood out of the liver, slowly inject 2 mL of normal saline through the PV. Drag down the liver by pulling the previously placed strap. Clamp the SHVC and part of the diaphragm with a Satinsky clamp.</li>
		<li>Transect the IHVC close to the parenchyma and the PV at the porta hepatis. Excise the liver by transecting the SHVC just above the liver. Remove the recipient liver quickly.</li>
	</ol>
	</li>
	<li>Attach a magnetic ring to the recipient&#39;s SHVC.
	<ol>
		<li>Insert the recipient&#39;s remaining SHVC into a magnetic ring.</li>
		<li>Fix the magnetic ring on a Satinsky clamp by magnetic attraction.</li>
		<li>Evert the SHVC over the magnetic ring until the vessel covers the edge of the ring.</li>
	</ol>
	</li>
	<li>Place the donor liver graft orthotopically and cover it with a cold wet gauze.</li>
	<li>Fill the lumen of the donor&#39;s and the recipient&#39;s SHVCs with normal saline solution. Remove air bubbles thoroughly to prevent air embolism. Finish the SHVC reconstruction by coupling the magnetic rings embedded in the donor&#39;s and recipient&#39;s SHVC together through magnetic force.</li>
	<li>Reconstruct the PV.
	<ol>
		<li>Tract the right and left branch of the recipient&#39;s PV by pulling an 8-0 prolene suture to maintain the tension of the PV.</li>
		<li>Move the clamp of recipient&#39;s PV down from the pylorus vein to the splenic vein in order to expose the vein fully.</li>
		<li>Incise the anterior wall of the recipient. Fill the lumen of the PV with normal saline solution.</li>
		<li>Hold the cuff extension of the donor&#39;s PV with a curved forceps.</li>
		<li>Insert the cuff body of the donor&#39;s PV into the recipient&#39;s PV while keep flushing the PV lumen with normal saline.</li>
		<li>Secure it with a circumferential 6-0 silk ligature. Re-establish the blood flow to the graft liver by releasing the clamps on the PV and SHVC.</li>
	</ol>
	</li>
	<li>Repeat step 4.11 on the IHVC to reconstruct the IHVC.</li>
	<li>Reconstruct the bile duct by a stent technique.
	<ol>
		<li>Incise a &#34;V&#34; on the anterior wall of the recipient common bile duct.</li>
		<li>Insert the donor stent into the lumen of the recipient BD and fix it with a 6-0 silk circumferential suture. Pull the sutures on the two bile ducts together and tie the sutures to bring the BD close to each other.</li>
		<li>Wrap omentum tissue around the anastomotic site to prevent bile leak.</li>
	</ol>
	</li>
	<li>Irrigate the abdominal cavity with warm normal saline solution. Close the abdomen incision in two layers with a continuous 3-0 non-absorbable surgical suture.</li>
	<li>Administer 16 mg/kg cefuroxime (an antibiotic) and 0.05 mg/kg buprenorphine (an analgesic) by subcutaneous injection after the operation immediately.</li>
	<li>Place the rat in a clean cage and allow food and water ad libitum.</li>
	<li>Inject cefuroxime (16 mg/kg) and buprenorphine (0.05 mg/kg) into the abdominal cavity every 12 hours for 3 days.</li>
</ol>

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The authors have nothing to disclose.

Many clinical progresses in liver transplantation can be attributed to animal studies. Rat OLT is a widely used and well accepted model in the research of organ preservation, transplant immunology, physiology and pathology. However, it is also a very complicated procedure and requires advanced microsurgical skill. Despite many improvements in the procedure of rat OLT, the SHVC anastomosis remained a challenging step. In this article, we describe a novel magnetic anastomosis technique for SHVC reconstruction in rat OLT. T...

The rat model of orthotopic liver transplantation (OLT) is essential for transplant research1,2. The first rat OLT was described by Lee et al. in 19733. In that model, all the vessels were reconstructed by the hand-suture technique. The hand-suture technique requires advanced microsurgical skills, which significantly limits its utilization. Since then, various modifications to the original protocol of rat OLT have been reported. Among them, the cuff technique for anastomosis of the portal vein (PV) and infrahepatic vena cava (IHVC) reported by Kamada et al. in 1979 is considered a major improvement to this model, as it significantly simplified the reconstruction procedures4. However, due to the short anterior wall of the recipients&#39; suprahepatic vena cava (SHVC), the cuff technique is very difficult to use for the reconstruction of the SHVC. Most researchers in this field still use the hand-suture technique for SHVC reconstruction, which makes it the bottleneck step in rat OLT5,6,7.
The magnetic anastomosis technique (i.e., magnamosis) is a method of connecting two vessels or other tubular structures using the attractive force between two magnets8,9,10,11. The magnetic force gradually compresses and remodels the tissue into a strong, sutureless anastomosis12,13. This compression anastomosis has been proven to be effective in humans14,15. We have designed a pair of magnetic rings specifically for the anastomosis of the SHVC in rats. Our recent study has shown that the magnetic anastomosis technique is superior to the hand-suture technique for SHVC reconstruction in rat OLT16. The purpose of this article is to provide a detailed, step-by-step protocol for SHVC reconstruction in rats using the novel magnetic anastomosis technique.

<table><tbody><tr><td>Anesthesia Machine</td><td>Harvard</td><td>&amp;nbsp;tabletop</td><td>Animal anaesthesia</td></tr><tr><td>PLX7000B HF Mobile Digital C-arm System</td><td>Perlong Medical</td><td>PLX7000B</td><td>It is mainly used for the angiography and photography of various operations</td></tr><tr><td>Syringe Pump</td><td>Mindray</td><td>BeneFusion SP5</td><td>intravenous infusion</td></tr><tr><td>Isoflurane</td><td>RWD life Science Co.</td><td></td><td>anesthetic:for the induction and maintenanceof anesthesia</td></tr><tr><td>iohexol</td><td>Shanghai General Pharmaceutical Co</td><td></td><td>&amp;nbsp;intravascular contrast media&amp;nbsp;&amp;nbsp;</td></tr><tr><td>heparin sodium injection</td><td>SPH No.1 Biochemical &amp;amp; Pharmaceutical Co., LTD&amp;nbsp;</td><td></td><td>&amp;nbsp;prevent the formation of thrombosis&amp;nbsp;</td></tr><tr><td>cefuroxime&amp;nbsp;</td><td>Glaxo Operations UK Limited&amp;nbsp;</td><td></td><td>an antibiotic</td></tr><tr><td>buprenorphine&amp;nbsp;</td><td>TIPR Pharmaceutical Responsible Co.,Ltd</td><td></td><td>an analgesic</td></tr><tr><td>curved microforceps</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>W40350</td><td>surgical tool</td></tr><tr><td>hemostatic forceps(straight)</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>J31010</td><td>surgical tool</td></tr><tr><td>hemostatic forceps(curved)</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>J31020</td><td>surgical tool</td></tr><tr><td>Satinsky clamp</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>XEC050</td><td>surgical tool</td></tr><tr><td>needle holder</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>J32010</td><td>surgical tool</td></tr><tr><td>microneedle holder</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>WBA040</td><td>surgical tool</td></tr><tr><td>notched forceps</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>J42010</td><td>surgical tool</td></tr><tr><td>tissue forceps(with hook)</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>J41010</td><td>surgical tool</td></tr><tr><td>tissue scissor</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>Y00040</td><td>surgical tool</td></tr><tr><td>surgical scissors</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>Y00030</td><td>surgical tool</td></tr><tr><td>micro scissors</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>MR-S121T</td><td>surgical tool</td></tr><tr><td>microvessel clips</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>XEC240</td><td>surgical tool</td></tr><tr><td>straight microforceps(titanium alloy)</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>WCC010</td><td>surgical tool</td></tr><tr><td>curved microforceps&amp;nbsp; (titanium alloy)</td><td>Shanghai Medical Instruments (Group) Ltd., Corp.</td><td>WCC020</td><td>surgical tool</td></tr></tbody></table>

a rat model of orthotopic liver transplantation using a novel magnetic anastomosis technique for suprahepatic vena cava reconstruction

The rat model of orthotopic liver transplantation (OLT) is essential for transplant research. It is a very sophisticated animal model and requires a steep learning curve. The introduction of the cuff technique for anastomosis of the portal vein (PV) and infrahepatic vena cava (IHVC) has significantly simplified the transplant procedure in rats. However, due to the short anterior wall of the recipients' suprahepatic vena cava (SHVC), the cuff technique is very difficult to use for the reconstruction of the SHVC. Most researchers in this field still use the hand-suture technique for SHVC reconstruction, which makes it the bottleneck step in rat orthotopic liver transplantation. The magnetic anastomosis technique (i.e., magnamosis) is a method of connecting two vessels using the attractive force between two magnets. Our recent study has shown that the magnetic anastomosis technique is superior to the hand-suture technique for SHVC reconstruction in rats. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using the novel magnetic anastomosis technique. In this model, the reconstruction of the PV and IHVC was performed by the standard cuff technique, while the reconstruction of the bile duct (BD) was performed by a stent technique. The hepatic re-arterialization was not performed. The magnetic anastomosis technique made SHVC reconstruction much easier and significantly shortened the anphepatic phase. After a reasonable learning curve, even researchers without advanced microsurgical skills can produce reliable and reproducible results using this rat model of OLT.

After approximately 10 attempts, the magnetic anastomosis technique for SHVC reconstruction was successfully mastered by a researcher who had no prior microsurgical training. The reconstruction of the SHVC took less than 2 min. The anhepatic phase for the recipient rats was approximately 10 min. No thrombosis, bleeding or angiostegnosis was observed at the SHVC anastomotic site at 1, 5 and 30 days after reperfusion. The inferior vena cavography was performed at 2 weeks after transplantati...

Watch this Scientific Journal Video about A Rat Model of Orthotopic Liver Transplantation Using a Novel Magnetic Anastomosis Technique for Suprahepatic Vena Cava Reconstruction at JoVE.com

A Rat Model of Orthotopic Liver Transplantation Using a Novel Magnetic Anastomosis Technique for Suprahepatic Vena Cava Reconstruction

The reconstruction of the suprahepatic vena cava (SHVC) remains a difficult step in rat orthotopic liver transplantation. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using a novel magnetic anastomosis technique.

The rat model of orthotopic liver transplantation (OLT) is essential for transplant research. It is a very sophisticated animal model and requires a steep ...

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9.8K Views.  First Affiliated Hospital, Xi'an Jiaotong University. The reconstruction of the suprahepatic vena cava (SHVC) remains a difficult step in rat orthotopic liver transplantation. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using a novel magnetic anastomosis technique. 

Video: A Rat Model of Orthotopic Liver Transplantation Using a Novel Magnetic Anastomosis Technique for Suprahepatic Vena Cava Reconstruction

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 ...

Surgical Procedures for a Rat Model of Partial Orthotopic Liver Transplantation with Hepatic Arterial Reconstruction

Orthotopic liver transplantation (OLT) in rats using a whole or partial graft is an indispensable experimental model for transplantation research, such as studies on graft preservation and ischemia-reperfusion injury 1,2, immunological responses 3,4, hemodynamics 5,6, and small-for-size syndrome 7. The rat OLT is among the most difficult animal models in experimental surgery and demands advanced microsurgical skills that take a long time to learn. Consequently, the use of this model has been limited. Since the reliability and reproducibility of results are key components of the experiments in which such complex animal models are used, it is essential for surgeons who are involved in rat OLT to be trained in well-standardized and sophisticated procedures for this model.
While various techniques and modifications of OLT in rats have been reported 8 since the first model was described by Lee et al. 9 in 1973, the elimination of the hepatic arterial reconstruction 10 and the introduction of the cuff anastomosis technique by Kamada et al. 11 were a major advancement in this model, because they simplified the reconstruction procedures to a great degree. In the model by Kamada et al., the hepatic rearterialization was also eliminated. Since rats could survive without hepatic arterial flow after liver transplantation, there was considerable controversy over the value of hepatic arterialization. However, the physiological superiority of the arterialized model has been increasingly acknowledged, especially in terms of preserving the bile duct system 8,12 and the liver integrity 8,13,14.
In this article, we present detailed surgical procedures for a rat model of OLT with hepatic arterial reconstruction using a 50% partial graft after ex vivo liver resection. The reconstruction procedures for each vessel and the bile duct are performed by the following methods: a 7-0 polypropylene continuous suture for the supra- and infrahepatic vena cava; a cuff technique for the portal vein; and a stent technique for the hepatic artery and the bile duct.

Orthotopic liver transplantation in rats is an indispensable experimental model for biomedical research. Here we present our surgical procedures for orthotopic rat liver transplantation with hepatic arterial reconstruction using a 50% partial graft.

Orthotopic liver transplantation (OLT) in rats using a whole or partial graft is an indispensable experimental model for transplantation research, such as ...

Heterotopic Auxiliary Rat Liver Transplantation With Flow-regulated Portal Vein Arterialization in Acute Hepatic Failure

In acute hepatic failure auxiliary liver transplantation is an interesting alternative approach. The aim is to provide a temporary support until the failing native liver has regenerated.1-3 The APOLT-method, the orthotopic implantation of auxiliary segments- averts most of the technical problems. However this method necessitates extensive resections of both the native liver and the graft.4 In 1998, Erhard developed the heterotopic auxiliary liver transplantation (HALT) utilizing portal vein arterialization (PVA) (Figure 1). This technique showed promising initial clinical results.5-6 We developed a HALT-technique with flow-regulated PVA in the rat to examine the influence of flow-regulated PVA on graft morphology and function (Figure 2).
A liver graft reduced to 30 % of its original size, was heterotopically implanted in the right renal region of the recipient after explantation of the right kidney.&#160; The infra-hepatic caval vein of the graft was anastomosed with the infrahepatic caval vein of the recipient. The arterialization of the donor&#8217;s portal vein was carried out via the recipient&#8217;s right renal artery with the stent technique. The blood-flow regulation of the arterialized portal vein was achieved with the use of a stent with an internal diameter of 0.3 mm. The celiac trunk of the graft was end-to-side anastomosed with the recipient&#8217;s aorta and the bile duct was implanted into the duodenum. A subtotal resection of the native liver was performed to induce acute hepatic failure. 7
In this manner 112 transplantations were performed. The perioperative survival rate was 90% and the 6-week survival rate was 80%. Six weeks after operation, the native liver regenerated, showing an increase in weight from 2.3&#177;0.8 g to 9.8&#177;1 g. At this time, the graft&#8217;s weight decreased from 3.3&#177;0.8 g to 2.3&#177;0.8 g.
We were able to obtain promising long-term results in terms of graft morphology and function. HALT with flow-regulated PVA reliably bridges acute hepatic failure until the native liver regenerates.

Auxiliary liver transplantation provides a temporary support in acute hepatic failure, until regeneration of the failing liver. The heterotopic auxiliary liver transplantation (HALT) with portal vein arterialization (PVA) renders sufficient liver function. We developed an analogous technique in the rat, to examine the influence of the portal vein arterialization on the morphology and function of the graft.

In acute hepatic failure auxiliary liver transplantation is an interesting alternative approach. The aim is to provide a temporary support until the ...

Rat Heterotopic Abdominal Heart/Single-lung Transplantation in a Volume-loaded Configuration

Herein, we describe a novel technique for heterotopic abdominal heart-lung transplantation (HAHLT) in rats. The configuration of the transplant graft involves anastomosis of donor inferior vena cava (IVC) to recipient IVC, and donor ascending aorta (Ao) to recipient abdominal Ao. The right upper and middle lung lobes are preserved and function as conduits for blood flow from right heart to left heart.
There are several advantages to using this technique, and it lends itself to a broad range of applications. Because the graft is transplanted in a configuration that allows for dyamic volume-loading, cardiac function may be directly assessed in vivo. The use of pressure-volume conductance catheters permits characterization of load-dependent and load-independent hemodynamic parameters. The graft may be converted to a loaded configuration by applying a clamp to the recipient&#8217;s infra-hepatic IVC. We describe modified surgical techniques for both donor and recipient operations, and an ideal myocardial protection strategy. Depending on the experimental aim, this model may be adapted for use in both acute and chronic studies of graft function, immunologic status, and variable ventricular loading conditions. The conducting airways to the transplanted lung are preserved, and allow for acute lung re-ventilation. This facilitates analysis of the effects of the mixed venous and arterial blood providing coronary perfusion to the graft.
A limitation of this model is its technical complexity. There is a significant learning curve for new operators, who should ideally be mentored in the technique. A surgical training background is advantageous for those wishing to apply this model. Despite its complexity, we aim to present the model in a clear and easily applicable format. Because of the physiologic similarity of this model to orthotopic transplantation, and its broad range of study applications, the effort invested in learning the technique is likely to be worthwhile.

We describe a novel technique for heterotopic abdominal heart-lung transplantation (HAHLT) in rats. The transplant configuration results in a partially loaded graft circulation, allowing direct functional assessment. This model may be employed for acute or chronic studies of function and immunologic status of the transplanted graft.

Herein, we describe a novel technique for heterotopic abdominal heart-lung transplantation (HAHLT) in rats. The configuration of the transplant graft ...

Orthotopic Hind Limb Transplantation in the Mouse

In vivo animal model systems, and in particular mouse models, have evolved into powerful and versatile scientific tools indispensable to basic and translational research in the field of transplantation medicine. A vast array of reagents is available exclusively in this setting, including mono- and polyclonal antibodies for both diagnostic and interventional applications. In addition, a vast number of genotyped, inbred, transgenic, and knock out strains allow detailed investigation of the individual contributions of humoral and cellular components to the complex interplay of an immune response and make the mouse the gold standard for immunological research. 
Vascularized Composite Allotransplantation (VCA) delineates a novel field of transplantation using allografts to replace "like with like" in patients suffering traumatic or congenital tissue loss. This surgical methodological protocol shows the use of a non-suture cuff technique for super-microvascular anastomosis in an orthotopic mouse hind limb transplantation model. The model specifically allows for comparison between established paradigms in solid organ transplantation with a novel form of transplants consisting of various different tissue components. Uniquely, this model allows for the transplantation of a viable vascularized bone marrow compartment and niche that have the potential to exert a beneficial effect on the balance of immune acceptance and rejection. This technique provides a tool to investigate alloantigen recognition and allograft rejection and acceptance, as well as enables the pursuit of functional nerve regeneration studies to further advance this novel field of transplantation.

This novel model for orthotopic hind limb transplantation in the mouse, applying a non-suture cuff technique for super-microvascular anastomosis, provides a powerful tool for in&#160;vivo mechanistic immunological research related to vascularized composite allotransplantation (VCA).

In vivo animal model systems, and in particular mouse models, have evolved into powerful and versatile scientific tools indispensable to basic and ...

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. To better understand the mechanism behind these surgical procedures, a rat partial liver transplantation (PLTx) model was established for relevant surgical studies. Because of the complexity of the rat PLTx model, a protocol with detailed descriptions is required. An article published previously reported a protocol in which ex vivo hepatectomy was used to achieve 50% rat PLTx. In contrast to this protocol, we introduced a re-arterialized PLTx with an in vivo 70% hepatectomy. An updated vessel-oriented hepatectomy was incorporated into the rat PLTx to refine the microsurgical procedure. The portal veins and hepatic arteries of the left lateral lobe and the median lobe were individually dissected and ligated before removal of the liver parenchyma, thereby decreasing the probability of bleeding in the remnant liver stump. Furthermore, an end-to-side vessel anastomosis between the common hepatic artery and the enlarged proper hepatic artery was introduced to re-arterialize the hepatic artery. By using this end-to-side vessel anastomosis technique, the diameter of the anastomosis was enlarged, thereby decreasing the difficulty of hand suture and maintaining a high rate of anastomotic patency. Moreover, the cuff anastomosis of the infrahepatic vena cava was slightly modified. A section of circumferential liver parenchyma around the vena cava of a recipient was preserved during cuff anastomosis to maintain the three-dimensional shape of the vascular lumen. This section of liver parenchyma was removed after completing the anastomosis. With this modification, the step involving placement of stay sutures was omitted, thereby further shortening the cuff anastomosis time. By using this protocol of rat PLTx, a low liver enzyme level, an intact liver lobular architecture and a high survival rate were achieved after microsurgery.

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Here, a protocol involving re-arterialized rat partial liver transplantation is presented. Specifically, 70% liver was resected in vivo by using an updated technique of vessel-oriented hepatectomy. The hepatic artery was reconstructed in an end-to-side manner. The cuff technique was modified to shorten the anastomosis time of the infrahepatic vena cava.

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. ...

Reduced Complications after Arterial Reconnection in a Rat Model of Orthotopic Liver Transplantation

The rat orthotopic liver transplantation (OLT) model is a powerful tool to study acute and chronic rejection. However, it is not a complete representation of human liver transplantation due to the absence of arterial reconnection. Described here is a modified transplantation procedure that includes the incorporation of hepatic artery (HA) reconnection, leading to a marked improvement in transplant outcomes. With a mean anhepatic time of 12 min and 14 s, HA reconnection results in improved perfusion of the transplanted liver and an increase in long-term recipient survival from 37.5% to 88.2%. This protocol includes the use of 3D-printed cuffs and holders to connect the portal vein and infrahepatic inferior vena cava. It can be implemented for studying multiple aspects of liver transplantation, from immune response and infection to technical aspects of the procedure. By incorporating a simple and practical method for arterial reconnection using a microvascular technique, this modified rat OLT protocol closely mimics aspects of human liver transplantation and will serve as a valuable and clinically relevant research model.

The goal of this study is to modify the rat orthotopic liver transplant model to better represent human liver transplantation and improve recipient survival. The presented method reestablishes hepatic arterial inflow by connecting the donor liver&#39;s common hepatic artery to the recipient liver&#39;s proper hepatic artery.

The rat orthotopic liver transplantation (OLT) model is a powerful tool to study acute and chronic rejection. However, it is not a complete representation ...

Organ Ischemia-Reperfusion Injury by Simulating Hemodynamic Changes in Rat Liver Transplant Model

Orthotopic liver transplantation (OLT) in rats is a tried and proven animal model used for preoperative, intraoperative, and postoperative studies, including ischemia-reperfusion injury (IRI) of extrahepatic organs. This model requires numerous experiments and devices. The duration of anhepatic phase is closely related to the time to develop IRI after transplantation. In this experiment, we used hemodynamic changes to induce extrahepatic organ damage in rats and determined the maximum tolerance time. The time until the most severe organ injury varied for different organs. This method can easily be replicated and can also be used to study IRI of the extrahepatic organs after liver transplantation.

This paper provides a detailed description of how to build an animal model of the anhepatic phase (liver ischemia) in rats to facilitate basic research into ischemia-reperfusion injury after liver transplantation.

Orthotopic liver transplantation (OLT) in rats is a tried and proven animal model used for preoperative, intraoperative, and postoperative studies, ...

Liver Transplantation in Mouse and Analyzing Allograft Patency

Successful Orthotopic Liver Transplantation in Mice Utilizing Microcomputed Tomography Angiography

Microcomputed tomography (microCT) angiography is an invaluable resource to researchers. New advances in this technology have allowed for high-quality images to be obtained of micro-vasculature and are high-fidelity tools in the field of organ transplantation. In this model of orthotopic liver transplantation (OLT) in mice, microCT affords the opportunity to evaluate allograft anastomosis in real time and has the added benefit of not having to sacrifice study animals. The choice of contrast, as well as image acquisition settings, create a high-definition image, which gives researchers invaluable information. This allows for evaluation of the technical aspects of the procedure as well as potentially evaluating different therapeutics over an extended duration of time. In this protocol, we detail an OLT model in mice in a stepwise fashion and finally describe a microCT protocol that can give high-quality images, which aid researchers in in-depth analysis of solid organ transplantation. We provide a step-by-step guide for liver transplantation in a mouse, as well as briefly discuss a protocol for evaluating the patency of the graft through microCT angiography.

Author Spotlight: Enhancing Transplantation Research Through MicroCT Angiography in Murine Models 

In this protocol, we discuss the implementation of a model of successful orthotopic liver transplantation (OLT) in mice. Additionally, adjuvants to further analyze allograft patency after successful OLT in a mouse are discussed as well, specifically utilizing microcomputed tomography (microCT) scans.

Microcomputed tomography (microCT) angiography is an invaluable resource to researchers. New advances in this technology have allowed for high-quality ...

Strategies for Efficient Vascular Anastomosis in Mouse Liver Transplantation

Vascular Reconstruction with the Cuff Technique in Mouse Orthotopic Liver Transplantation

Mouse orthotopic liver transplantation is an effective methodology for investigating the underlying mechanisms of liver ischemia and reperfusion injury. However, the technical challenges pose a barrier to utilizing this valuable experimental model and passing on these skills to the next generation. The most challenging aspect of this procedure is vascular reconstruction, including the portal vein (PV), infrahepatic inferior vena cava (IHIVC), and suprahepatic inferior vena cava. The use of plastic cuffs, rather than sutures, allows for smoother PV and IHIVC reconstruction. Vessels are reconstructed by attaching a cuff made from an intravenous catheter to the tip of the graft vessel and interposing the cuff into the recipient vessel. The two most crucial aspects are properly visualizing the inner lumen of the vessel and avoiding the use of excessive force. Our aim is to provide a technical overview of vascular reconstructions using the cuff technique in recipient surgery. These technical tips for the cuff technique are expected to help microsurgeons facilitate vascular reconstruction and advance their research.

Author Spotlight: Exploring Cold Ischemia and Warm Reperfusion Injury in Fatty Liver Transplantation

This protocol provides technical information for vessel reconstruction using the cuff technique in mouse orthotopic liver transplantation.

Mouse orthotopic liver transplantation is an effective methodology for investigating the underlying mechanisms of liver ischemia and reperfusion injury. ...

A Rat Model of Orthotopic Liver Transplantation Using a Novel Magnetic Anastomosis Technique for Suprahepatic Vena Cava Reconstruction

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Chapters in this video

Orthotopic Liver Transplantation in Rats

Surgical Procedures for a Rat Model of Partial Orthotopic Liver Transplantation with Hepatic Arterial Reconstruction

Heterotopic Auxiliary Rat Liver Transplantation With Flow-regulated Portal Vein Arterialization in Acute Hepatic Failure

Rat Heterotopic Abdominal Heart/Single-lung Transplantation in a Volume-loaded Configuration

Orthotopic Hind Limb Transplantation in the Mouse

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Reduced Complications after Arterial Reconnection in a Rat Model of Orthotopic Liver Transplantation

Organ Ischemia-Reperfusion Injury by Simulating Hemodynamic Changes in Rat Liver Transplant Model

Successful Orthotopic Liver Transplantation in Mice Utilizing Microcomputed Tomography Angiography

Vascular Reconstruction with the Cuff Technique in Mouse Orthotopic Liver Transplantation