In Vitro Model for the Study of Platelet-Vessel Wall Interactions Following a Freeze-Thaw Injury.

摘要

Platelet-endothelial cell interactions are important for maintaining normal hemodynamics. The intact endothelial cell lining is considered non-thrombogenic, but following disruption of the lining platelets will bind to the subendothelium. There is also much conjeture concerning the affinity of platelets for damaged endothelial cells. A model is described for the study of platelet-arota vessel wall interactions following freeze-thaw insult. Using this model, control aortas (37C) perfused with platelet rich palmsa (PRP) or gel filtered platelets did adhere to areas of exposed subendothelium. Following freeze-thaw insult (-15C of -20C), the endothelial lining was grossly disrupted. The remaining endothelium was severely damaged, demonstrating holes and pits in the plasma membranes and separation of adjacent cell borders. Platelets readily adhere to the subendothelium, but were rarely noted in sole contact with the damaged endothelium. Platelet binding did not result in morphological changes, degranulation or aggregation. Using transmission electron microscopy, platelets were noted in contact with amorphous material and microfibrils but not collagen fibers of the subehdothelium. It is concluded that this model is suitable for the in vitro study of certain hemodynamic phenomena associated with blood vessel freeze-thaw injury. In addition, freeze-thaw damage in this in vitro model, indicated that platelet-vessel wall interactions were limited to areas of exposed subendothelium.