USEFULNESS OF PLATELET-CR-51 LABELING FOR MEASUREMENT OF PLATELET DEPOSITION ON SUBENDOTHELIUM

The subendothelium of the rabbit abdominal aorta was mechanically removed by introduction of a ballon catheter into the aorta. Perfusion was performed with human citrated blood containing 95% 51Cr-labeled platelets. The number of platelets fixed to a square centimeter of subendothelium depended on the platelet count in the perfused blood. This correlation was statistically significant. The regression coefficient characterized the linear relationship between platelet deposition and platelet concentration under standard conditions of anticoagulation, hematocrit and flow rate. The linear relationship found between deposition and circulating concentration indicates that a cumulative phenomenon due to aggregation was eliminated. The global platelet deposition resulting from adhesion and aggregation can be estimated by the use of a moderate citrate concentration.