The Role of Fibronectin in Arterial Subendothelium in Platelet Adhesion

The role of fibronectin in vascular subendothelium in platelet adhesion after the removal ofthe endothelium of aorta was studied in normal rabbits. The thoracic aortae were treated with 1%Nonidet P-40 for 5 min and with 0. 3 mol/L KCl for 10 min. The whole endothelium was re-moved and a large amount of fibronectin in the subendothelium was exposed. Autogenous platelet-rich plasma was isolated and platelets were labeled with 1:1000 acridine orange. The adheredplatelets were washed away with 2% SDS solution. Finally, the intensity of fluorescence of the wash-ing fluid was measured with a spectrofluorophotometer. The animals were divided into 4 groups:(1) normal endothelium group. (2) lysed endothelium group, (3) lysed endothelium and guineapig anti-rabbit fibronectin antisera inhibition group, (4) lysed endothelium and guinea pig normalsera control group. The adhesion of platelets in the 2nd group was taken as 100%. The resultsshowed that after the treatment of anti-rabbit fibronectin antisera the platelet adhesion onsubendothelium was inhibited up to 70. 1%. It is suggested that the fibronectin in subendotheliumplays an important role in platelet adhesion.

The Role of Fibronectin in Arterial Subendothelium in Platelet Adhesion

The role of fibronectin in vascular subendothelium in platelet adhesion after the removal of the endothelium of aorta was studied in normal rabbits. The thoracic aortae were treated with 1% Nonidet P-40 for 5 min and with 0. 3 mol/L KCl for 10 min. The whole endothelium was re- moved and a large amount of fibronectin in the subendothelium was exposed. Autogenous platelet- rich plasma was isolated and platelets were labeled with 1:1000 acridine orange. The adhered platelets were washed away with 2% SDS solution. Finally, the intensity of fluorescence of the wash- ing fluid was measured with a spectrofluorophotometer. The animals were divided into 4 groups: (1) normal endothelium group. (2) lysed endothelium group, (3) lysed endothelium and guinea pig anti-rabbit fibronectin antisera inhibition group, (4) lysed endothelium and guinea pig normal sera control group. The adhesion of platelets in the 2nd group was taken as 100%. The results showed that after the treatment of anti-rabbit fibronectin antisera the platelet adhesion on subendothelium was inhibited up to 70. 1%. It is suggested that the fibronectin in subendothelium plays an important role in platelet adhesion.