Begin by spraying the properly euthanized mouse with 75%alcohol to disinfect the skin. Then place the mouse in a supine position. Lift the skin of the animal's abdominal region, and using surgical scissors, make a small incision in it.
Then using the scissors, bluntly separate the skin and abdominal muscles from the pelvis to the neck, along the ventral midline. Expose the heart and lungs by cutting the diaphragm and ribs along both sides of the midline. Next, carefully remove the liver, spleen, bowels, and kidney, avoiding damage to the intestinal wall.
Following that, remove the lungs and esophagus. Now gently lift the heart using forceps held in one hand and separate the aorta from the spine with surgical scissors held in the other hand. Then place the heart and aorta in a 60 millimeter petri dish, containing antibiotic supplemented PBS.
Retrieve the microsurgical forceps and microsurgical scissors from the alcohol, and rinse them in 25 milliliters of PBS to remove excess alcohol. Working under a stereo microscope, remove the thymus and other tissues from the heart and aorta. Then remove the heart, leaving the aorta with the perivascular adipose tissues or PVATs.
Transfer the aorta along with the PVATs to a clean 60 millimeter petri dish containing antibiotic supplemented PBS. Using one pair of microsurgical forceps, hold the aorta, and using another pair, pull off the attached adipose tissues to separate the PVATs from the aorta. Remove as much vascular tissue as possible while causing minimal harm to the PVATs.
Finally, transfer the collected PVATs into a two milliliter microcentrifuge tube, containing antibiotic supplemented, high glucose, DMEM, placed on ice.
