Mouse Model of Oleic Acid-Induced Acute Respiratory Distress Syndrome

This model induces in mice several key features of the acute respiratory syndrome, such as edema, alveolar permeability, and leukocyte filtration, thus helping researchers better understand ARDS pathophysiology Using oleic to induce RDS better mimics these conditions, while avoiding the risk of altering bloods pH and cause emboli when using pure oleic acid. A well done sedation is very important. Make sure the animal is deeply sedated throughout the procedure.

This way, no sudden expand may hinder the of the Doing this procedure step-by-step, allows any associates to perform this procedure correctly. Also, this technique may be applied to study different diseases by changing the injector substance. Start preparing the sodium oleate solution by adding sodium hydroxide tablets or solution in the ultrapure water to elevate the pH to 12 to 13.

Then, add oleic acid drop by drop under constant agitation in an ultrasonic bath at 37 degrees Celsius. Next, to perform intratracheal administration of oleic acid, lay the anesthetized mouse in a dorsal decubitus position on a heating pad at 37 degrees Celsius, and make an incision of 0.5 to 1 centimeter in V-shape at the thyroid level. Remove the thyroid to expose the trachea, and inject 50 microliters of the oleate solution.

After the injection, close the incision with a synthetic non-absorbable monofilament suture. Then, return the mouse to the home cage and monitor it until complete recovery from the surgery. For intravenous administration, use an ultra fine needle to inject oleic acid into the orbital plexus of the anesthetized mouse.

To collect the bronchoalveolar lavage fluid, lay the euthanized mouse in the dorsal decubitus position and make a 1 centimeter incision in the anterior region with surgical scissors. Expose it to the trachea and make a small cut to introduce a 20 gauge intravenous catheter. Connect the catheter to a 1 milliliter sterile syringe to slowly inject 500 microliters of sterile saline into the lungs.

Then, aspirate the bronchoalveolar lavage fluid with the same syringe. After repeating the fluid collection 3 to 5 times, transfer the fluid to a sterile micro tube and place the tube on ice. In representative analysis, oleic acid injection increased total leukocytes in intratracheal and intravenous routes compared to the control.

Intratracheal administration of oleic acid induces the production of inflammatory mediators, such as tumor necrosis factor alpha, interleukin 6, and interleukin 1 beta, compared to the control. Intratracheal and intravenous administration of oleic acid also increased total protein concentration in the bronchoalveolar lavage fluid. Intratracheal and intravenous injection enhanced Prostaglandin E2 concentration and lipid bodies formation than the control.

Further, hematoxylin and eosin staining. Illustrated tissue disruption, hemorrhage and leukocyte infiltration after intravenous and intratracheal administration of oleic acid. After the research performed the technique, the collected samples could be analyzed by to evaluate protein These procedures can help research and understand how can mimic ARDS, and choose and develop new treatments that