Acute Biliary Pancreatitis Model: A Method to Generate Acute Biliary Pancreatitis Mouse Model via Pancreatic Duct Infusion

The pancreatic duct transports digestive enzymes and connects with the common bile duct near the intestine. These ducts form a channel where bile salts activate digestive enzymes before exiting into the intestine.

When gallstones obstruct this channel, bile flows backward, activating digestive enzymes in the pancreas itself, leading to acute biliary pancreatitis - a severe inflammatory condition. To mimic this condition in a mouse model, prep an anesthetized mouse in the supine position.

Incise the upper abdomen, below the chest. Then, pull the upper portion of the small intestine with pancreas and fix its lateral ends to access the periampullary region - a complex anatomical structure that includes the pancreatic duct opening.

Secure the proximal and distal ends of the common bile duct to prevent any leakage to other organs. Next, connect a syringe filled with sodium taurocholate solution to an infusion pump. Sodium taurocholate is a bile salt that activates enzymes for fat digestion.

Now, insert the needle into the periampullary region and start perfusing at optimum speed and concentration for the desired duration. After perfusion, remove the needle and sutures. Place the intestine back into the peritoneum.

Suture the incision. Allow the mouse to recover. Eventually, sodium taurocholate enters the pancreas and activates digestive enzymes, causing pancreatic damage.

After checking the depth of anesthesia with a toe pinch, clean the abdominal area of an anesthetized mouse with a 5% povidone-iodine solution. Using a trimmer, remove hair between the chest and lower abdomen, and clean an approximately 2 square centimeter surgical area with 70% alcohol. Immobilize the animal on the surgical board and use scissors to cut 5 millimeters of the skin horizontally on the upper part of the abdomen and 1 centimeter below the xiphoid process. Repeat the cut on the peritoneum.

To perform the laparotomy with minimal exposure of the cavity, using a tractor pull the liver towards the head approximately 1 centimeter from the intestine and locate the region of the pancreas and the duodenum. Using forceps, lift the liver towards the animal head. By gently pulling the portion of the small intestine, fix the two lateral ends with a 6-0 polypropylene suture for a better view of the distal portion of the common bile duct tube.

Using a microvessel clip, occlude the proximal common bile duct temporarily. Expose the organ out of the abdominal cavity. Then, make a temporary occlusion of the distal common bile duct with an 8-0 suture. To access the common bile duct, puncture the periampullary region, which appears as a whitish part of the small intestine's wall, with a 0.4-millimeter needle connected to a 0.54-millimeter polyethylene tube. Start the infusion pump for 2.5% sodium taurocholate solution infusion at a constant speed of 10 microliters per 10 grams of body weight for 3 minutes.

After the infusion, remove the microvessel clip, the temporary 8-0 suture, and the injection needle from the pancreatic bile duct. Suture the abdomen with a 6-0 non-absorbent monofilament polypropylene suture. The time between the laparotomy and the end suture should not be more than 30 minutes. After the surgery, house the animals in polyethylene boxes lined with wood shavings and water and food ad libitum.