A Murine Model of Arterial Restenosis: Technical Aspects of Femoral Wire Injury

The goal of this procedure is to create prominent intimal hyperplasia induced by wire injury in the femoral artery in mice. This is accomplished by first making a longitudinal skin incision on the left thigh. Next, the femoral artery is found and looped at three important anatomical regions, the superficial femoral artery or SFA common femoral artery, or CFA and deep femoral artery, or DFA.

Then a small hole is made on the DFA wall and a metallic wire is inserted and advanced into the CFA where it is left for one minute. Finally, the wire is retrieved and the DFA is ligated at two points. Ultimately, h and e staining of cross-sections shows thick intimal hyperplasia in the femoral artery.

Generally, individuals new to this method will struggle because of two reasons. First, they have to find the right access artery from deep inside the muscle. Second, they have to insert a wire, which is roughly three times thicker than the access artery After anesthetizing a male C 57 plaque six mouse.

According to the text protocol, confirming proper anesthesia and applying eye ointment place the mouse in the supine position, the left limb slightly abducted and the knee joints slightly flexed. Once the hair has been shaved and the region has been disinfected with fine tweezers, open the thin fascia overlying the superficial femoral artery, and use nine zero nylon suture. To loop the SFA use mosquito forceps to hold the suture and gently pull it slightly downward to make further dissection easier.

Continue to dissect the artery to expose the common femoral artery or CFA. Then use nine zero nylon suture. To loop the CFA while holding both suture loops.

Pull the CFA suture loop upward and the SFA suture loop downward to uncover the bifurcation of the SFA and the deep femoral artery or DFA, which branches towards the thigh muscle. Next, using extra caution loop the DFA taking care to avoid the adjacent vein that is tangled beneath the artery. In case of bleeding from the vein, use GREs to apply a 30 to 62nd compression to produce hemostasis.

Once the DFA is looped, make sure all three suture loops are at their correct positions. Then proceed to dissect the DFA distally and ligate the artery at a point as far away as possible from the bifurcation. Cut, extra suture, but leave a certain length for using mosquito forceps to hold the two ends to stabilize the DFA, which will make the wire insertion easier to insert the wire via the DFA, begin by straining the C-F-A-S-F-A and DFA sutures.

To establish a temporary hemostat, loosen the CFA suture loop and use dull tipped micro tweezers to gently clamp or squeeze the DFA several times. This will expand the arterial diameter remarkably to ease wire insertion. Next with sharp tipped micro tweezers, make a small V-shaped nip in the DFA and pinch the flap.

Use PBS to moisten the wire thoroughly and without using force. Insert it through the adequately dilated hole on the DFA gently advance the wire toward the iliac artery. While loosening the suture loop around the CFA five to eight millimeters is enough to cover the length of the CFA in most cases.

After inserting the wire to the optimal length, leave it for one minute to overstretch the arterial wall, use PBS to moisten the wire and arteries to prevent drying while waiting. Place another nine zero suture around the DFA proximal to the wire insertion point to be used later. To close the hole of the DFA to retrieve the wire and resume blood flow.

Use vessel cannulation forceps to hold the wire and gently pull it back, rotating it if necessary to overcome any resistance due to sticking to the arterial wall. After retrieving the wire, use nine zero suture to ligate the DFA as a point closer to the bifurcation, ensuring that blood outflow to the SFA will not be jeopardized. Loosen the SFA and CFA suture loops to resume normal blood flow.

The CFA will be well expanded by the wire insertion, close the skin, carry out postoperative care, and later harvest the wire injured femoral artery. According to the text protocol, after harvesting the femoral artery, the tissue was fixed in paraldehyde and embedded in param shown. Here are h and e stain slices of the embedded tissue.

Neoma formation can be clearly seen inside the wire injured femoral artery. The lumen area internal elastic lamina, or IEL area, and the external elastic lamina or EEL area from the cross section are indicated in this panel. These values can be used to calculate the intimate area by subtracting the lumen area from the IEL area and the media area.

By subtracting the IEL area from the EEL area, the intimate area media area ratio is used to compare the neointima formations between different experimental groups. Once mastered, this technique can be done in 20 minutes if it is performed properly.