Ultrastructural Studies of Aortic Endothelial Injury and Regeneration

Jang, Gium Mi; Kim, Dong Hoon; Kwak, Jyung Sik; Sohn, Tae Joong

Abstract

Author performed this experiment to define the most important factor preventing the intimal thickening. An endothelium of abdominal aorta in the rat was denuded by two different wires having same caliver. The degree of injury was limited to the endothelial cells in one, and extended to the internal elastic lamina in another. The results showed that at 72 hours, in the case of superficial injury, the entire injury site was covered by new regenerating cells, but in the case of disruption of the internal elastic lamina, the migrating smooth muscle cell completely reached into the intima and resulted in intemal thickening. Similar findings persisted to 1 week later. Above results suggest the most important factor preventing the intimal thickening in endothelial injury is the depth of the injury which limited within the endothelial cells without extending into the internal elastic lamina and medial smooth muscle cells.