Rat Carotid Artery Balloon Injury Model

All animal experiments were conducted in compliance with the Guidelines for the Care and Use of Research Animals under protocols approved by Washington University’s Animal Studies Committee. Mature, male Sprague-Dawley (SD) rats (Charles River Laboratories, Inc, Wilmington, Massachusetts) were used for all experiments.

The rat carotid artery balloon injury procedure was carried out according to published methods.⁹ Briefly, 350 to 700 g male SD rats were anesthetized with isoflurane (1-3%). The trifurcation of the right common carotid artery with the external and internal carotid branches was exposed by a ventral skin incision and blunt dissection. Sterile sutures were placed around the common and external carotid artery (ECA) branch in order to isolate the ECA branch for vascular access and to control blood flow. A deflated sterile balloon catheter (2F Fogarty, Edwards Lifesciences, Irvine, California) was introduced through an arteriotomy in the external branch and passed proximally down the common carotid into the aorta. Slight inflation of the balloon with saline and withdrawal of the catheter identified when it began to engage the brachiocephalic artery. The balloon pressure was then decreased just enough to allow the withdrawal of the catheter with rotation along the full length of the common carotid artery to the area of the carotid trifurcation. The balloon was then deflated, and this procedure was repeated 3 times. The arteriotomy was closed proximally, and blood flow through the common carotid artery was restored. The contralateral (left) common carotid artery and branches were similarly exposed without ligation or catheterization as a sham control.