A method of testing platelet aggregation in native whole blood.

A method of testing collagen induced platelet aggregation and ATP release in native (= non anticoagulated) whole blood by monitoring the electrical impedance in the Chrono Log Whole Blood Aggregometer is reported. It is the first simple method by which aggregation of human platelets can be measured in their natural environment. In normal individuals lower threshold collagen concentrations could induce platelet aggregation as determined with this method than in the other tested methods (impedance method with citrated blood, optical method in platelet rich plasma). The aggregation response was not inhibited by hirudin or heparin in therapeutic dose. The luminescence channel of the Whole Blood Aggregometer permits measurements of ATP release in native whole blood.