A detailed temporal sequence of vessel wall changes in a rabbit model
of balloon angioplasty, to the iliac arteries, at 30 min, 2 h, day 1,
day 3, day 7, day 14, 1 month, and 3 months was established using ligh
t microscopy, immunostaining for proliferating cell nuclear antigen, a
nd electron microscopy. Complete endothelial denudation with extensive
platelet and fibrin deposition was evident early. Intimal thickening,
characterized by myointimal hyperplasia, was observed at day 7 and re
ached a maximum at 1 month. Re-endothelization was complete by day 14.
Cellular proliferation, seen early at day 1, reached a maximum at day
7 for the media and day 14 for the intima before returning to baselin
e levels by 1 month. This simple model of angioplasty with its reprodu
cible myointimal hyperplasia should prove useful for assessing any pot
ential agents for inhibiting this process.