The fate of mural thrombi produced by injury in the ear artery of the rabbit.

By exposing the central artery of the ear of a rabbit through a skin incision it is possible regularly to produce platelet thrombi in the lumen by a unipolar electrical stimulus. By closing the skin incision the fate of such thrombi has been followed up to 50 days. One to 2 hours after injury endothelium has disappeared completely and the media is destroyed. A thrombus consisting of amorphous material and platelets is present on the luminal surface. During repair endothelium grows over the thrombus and smooth muscle cells migrate into it. These cells gradually become mature, a stage reached at about 15 days, at which time elastic fibres and collagen appear between the muscle cells. At 50 days there are several layers of smooth muscle cells interspersed with collagen and elastic fibres interleaved between endothelium and internal elastic lamina.