Effects of hyperbaric oxygen on expression of fibrinolytic factors of human endothelium in a simulated ischaemia/reperfusion situation

Abstract

Background : Treatment with hyperbaric oxygen (HBO 2 ) is controversial when treating disorders other than decompression sickness. Still, HBO 2 is a treatment modality that has gained recognition in certain situations of ischaemia reperfusion. However, not much is known about its effect on the endothelial cells. Based on earlier studies, the hypothesis was that HBO 2 treatment stimulates the release of fibrinolytic factors. The aim of the study was to investigate the effect of HBO 2 treatment on cultured endothelial cells in a simulated ischaemiareperfusion model. Methods : To mimic the clinical situation during ischaemia reperfusion, endothelial cells were subjected to anoxia for 8 h, followed by reperfusion with either HBO 2 or normobaric air for 1.5 h, and compared with an untreated control that was not exposed to anoxia. Components investigated were the fibrinolytic stimulator tissue plasminogen activator (t-PA), urokinase plasminogen activator (uPA) and the antagonist, plasminogen activator inhibitor type one (PAI-1). Results : Immediately after 8 h of total anoxia and reoxygenation with HBO 2 (for 1.5 h), the mean (SEM) concentrations of t-PA, PAI-1 and uPA were significantly increased compared to the other groups. The difference between the normobaric and control groups, measured at 1.5 h, 6 h and 24 h post-anoxia, persisted throughout the experiment. Conclusion : In this ischaemia-reperfusion model, HBO 2 stimulates the release of fibrinolytic factors. These observations might be relevant in trauma care in preventing thromboses and/or microembolization following ischaemia-reperfusion.

• Endothelial Cells Hyperbaric Oxygen Reoxygenation T-PA