Filament Insertion-based Transient Stroke Model: A Surgical Procedure to Perform Middle Cerebral Artery Occlusion in Murine Brain

The neck region of the mouse has a pair of common carotid arteries, or CCA. As the left CCA advances toward the head region, it bifurcates into the external carotid artery, or ECA, and the internal carotid artery, or ICA. The ICA branches further, forming the middle cerebral artery, or MCA, which supplies oxygenated blood to the brain. Any disruption to the blood flow within the MCA can cause a stroke.

To perform transient middle cerebral artery occlusion, or MCAO, place an anesthetized mouse in the supine position. Make a small incision on the neck. Retract the skin and muscle layers to locate the CCA and ligate it, stopping the blood flow toward the brain. Subsequently, use a removable surgical clip to ligate the ICA transiently.

Place two slightly distant sutures to ensure a tight and a loose ligation around the ECA before reaching the bifurcation point of the ICA. Make a small incision between the two ECA sutures and insert the silicon-coated filament intraluminally into the ECA.

Remove the clip clamping the ICA. Advance the filament further through the length of the ICA until the filament head blocks the origin of the MCA. With all the sutures in place, close the surgery site. Return the mouse to the cage and monitor it.

Transient MCAO causes an abrupt reduction in the blood flow, eventually leading to a stroke.