Platelet activity, reactivity and platelet-leukocyte conjugate formation before and after exhaustive or moderate...

Diabetes mellitus alters blood coagulation and platelet function which supports the suggestion that diabetes mellitus is a hypercoagulable state. Firstly the aim of the study was to investigate if differences in platelet activity, reactivity and platelet-leukocyte conjugate (PLC) formation can be observed in subjects with IDDM; secondly, if differences can be seen between the diabetic and control group concerning exercise-induced changes in platelet activation and conjugate formation; and thirdly, if different types of exercise lead to different patterns in platelet activation. Sixteen subjects with IDDM and 16 controls underwent a maximal step test and an endurance test (90% IAT, 45 min). Blood samples were taken after 30 min rest, and immediately and 1 h after completion of exercise. CD62P expression and differentiated platelet-leukocyte conjugates (CD45, CD14, CD41) were detected flow-cytometrically with and without stimulation with TRAP-6. The rest values of the platelet-granulocyte (PGC) and platelet-lymphocyte conjugates (PLyC) were higher (P < 0.05) in the diabetics. After exercise, platelet reactivity (CD62P-TRAP; P < 0.05) but not the activity (CD62P-unstimulated), as well as all different conjugates with or without stimulation were increased (P < 0.05) independently from the group. Differences according to the type of exercise were barely observable. IDDM without vascular complications leads to higher PCG and PLyC at rest and to identical increases in differentiated platelet-leukocyte formation after exercise in comparison with matched controls.