Protective effect of defibrotide on perfusion induced endothelial damage

In the present study, in vitro effects of Defibrotide (D) on perfusion-indu ced changes in the morphology of endothelium were investigated by scanning (SEM) and transmission (TEM) electron microscope. Human umbilical cord vein s were incubated or perfused with platelet-rich plasma alone (PRP) or plate let-rich plasma with Defibrotide (PRP + D) at 3ml/min or 14ml/min and the c hanges observed were compared. SEM examination of luminal surfaces demonstr ated that perfusion with high flow rates may damage endothelial cells and l ead to morphological changes which may be prevented by the presence of Defi brotide in the perfusate, Also, the marked reduction in the number of adher ed platelets on luminal surface of veins incubated or perfused with Defibro tide compared to veins treated with platelet-rich plasma only revealed that Defibrotide has anti-thrombotic effects. TEM examination of ruthenium red (RR) stained thin sections of veins demonstrated that perfusion disrupts th e glycosaminoglcan (GAG) coat on endothelial cells. But the presence of D i n the perfusate preserves the integrity of GAG, indicating further cytoprot ective effects of the drug on endothelium. (C) 2000 Elsevier Science Ltd. A ll rights reserved.