Abstract
Microangiopathy and vaso-occlusive disease are recognized complications of diabetes mellitus, and platelets are probably involved in the pathogenesis of these disorders.
Increased platelet adhesiveness, an increased tendency to undergo spontaneous aggregation, and a heightened sensitivity to aggregating agents such as ADP., adrenaline and collagen, have been demonstrated in diabetic patients with vascular complications. However, there are considerable vari ations in these parameters and individual values for both control and diabetic subjects are so dispa rate that it is generally not possible to make distinctions between them on an individual basis.
β-Thromboglobulin represents a recently isolated platele-tspecific protein that is released during platelet aggregation. The sensitivity and precision of the j3-thromboglobulin radioimmunoassay have been proved satisfactory. Plasma β-thromboglobulin levels were therefore measured in blood samples from healthy control subjects and from diabetic patients with and without microangiopathic complications. The mean level of plasma β-thromboglobulin in the healthy controls was 24 ng/ml (n =36). The patients with retinopathy had significantly elevated β-thromboglobulin levels (56.2 33.5ng/ml, n=18), although no correlation was found between the plasma β-thromboglobulin and the extent or activity of the diabetic complications. There was no significant difference between the diabetic group without vascular complications and the healthy controls.
Diabetic patients in the stroke process of cerebral thrombosis at the time of examination had markedly elevated β-thromboglobulin levels, while diabetic patients in an established thrombotic state showed normal blood levels of β-thromboglobulin.
The above results are considered to provide additional evidence that platelet function in dia betes mellitus is abnormal. If elevation of the thromboglobulin concentration proves to be an early change associated with the development of widespread vascular lesions, use of this parameter in the assessment of the risk of developing vascular change may become possible.
