Endothelial denudation and myointimal thickening in the rat carotid artery induced by the passage of bubbles.

A new technique for the selective removal of endothelium in the rat carotid artery has been developed, and subsequent events in the vascular wall have been examined. To achieve de-endothelialization, more than 2,000 bubbles of nitrogen in phosphate-buffered saline are passed through a temporarily isolated segment of rat carotid over a period of 3 min. Bubbles are generated by a simple apparatus, consisting of a pressurized tilting chamber and catheter. Endothelium is removed while subendothelial basement membrane and other subjacent structures remain intact. Platelets attach to the denuded surface within minutes after re-establishment of blood flow. Myointimal thickening is found at 5 weeks and 4 months after de-endothelialization. The method is quite reliable and will facilitate further studies of reactions to carotid endothelial injury in young adult rats.