The Haemostatic Effect of 51Cr-Labelled Blood Platelets An Experimental Study in the Rabbit

Abstract

The hemostatic effect of 51Cr-labeled platelets was studied in 5 rabbits made thrombocytopenic (35,000/.mu.l blood) by whole body ionizing irradiation. Bleeding times were recorded after standardized cuts on the inner side of the rabbit''s ear, a method with an acceptable reproducibility. The animals were then each transfused with concentrates of labeled platelets from 2 healthy donor rabbits. This increased the platelet counts to about 2 .times. 105/.mu.l blood. Bleeding time values were markably prolonged before transfusion and became normalized when tested 1 and 4 h after transfusion. In 3 control experiments, where unlabeled platelet rich plasma was transfused to thrombocytopenic recipients, a similar shortening of the bleeding time was observed. 51Cr-labeled platelets apparently retain hemostatic ability comparable to non-labeled platelets, when circulating in a recipient animal.