The investigation of platelets in the thrombotic diatheses

1. Consideration of the morphology of a thrombus shows the presence of platelets and many confounding factors and processes. 2. This suggests that in vivo a balance is stuck between activation and inactivation. 3. Laboratory evidence of platelet involvement in thrombus will be reviewed. While a short platelet survival is proof of platelet involvement, "damage" can result in "exhausted" platelets which circulated for a normal time. The following tests will be considered; The non-specific heparin thrombin clotting time; serotonin release; malondialdehyde production and platelet factor 4 and (3 thromboglobulin and platelet aggregation. 4. The contribution of the vessel wall will be considered. 5. Successful therapeutic treatment of thrombosis if rightly understood should enlarge our knowledge of the mechanics involved.