Does heparin therapy lead to platelet activation and prolongation of PFA-100 closure time?
Unfractionated heparin leads to direct platelet activation and increases platelet aggregation in vitro. Unfractionated heparin causes prolongation of the collagen/adenosine diphosphate closure time in PFA-100 testing, possibly as a result of direct binding to von Willebrand factor in solution and interference with von Willebrand factor-glycoprotein Ib binding.
The present study demonstrated preservation of vascular smooth muscle and endothelium-dependent relaxations after prolonged hypothermic storage in UW solution. Furthermore, storage in this solution preserved basal release of nitric oxide.