Effects of somatostatin on the behavior of thromboxane B2 and B-thromboglobulin in type 1 diabetes.

Somatostatin, as an adjunct to insulin in the treatment of poorly controlled type 1 diabetes, has been recently suggested. However, some authors, after injection of the polypeptide, detected a reduction in number and aggregation of platelets, others instead, reported a proaggregatory effect of the drug. To answer these questions, the plasma levels of proaggregatory thromboxane A2 and of B-thromboglobulin, marker of the platelet activation, were studied in nine control subjects and in thirteen insulin dependent diabetic patients before and during the endovenous injection, for three hours, of somatostatin (250 micrograms in bolus followed by infusion of 100 micrograms/h). In both groups, 30 min after the infusion of somatostatin, a fall of thromboxane B2, stable metabolite of thromboxane A2 and an increase of B-thromboglobulin were respectively observed. Their greatest figure was reached after 120 min and their levels did not return to basal values within the end of the observation. In diabetics, during the infusion of somatostatin, thromboxane B2 presented normal percentual falls while B-thromboglobulin showed increases which were lower than controls. In conclusion, the effect of somatostatin implied in the relative lower increase of B-thromboglobulin, seems connected to the precedent continuous activation of circulating platelets, the one, responsible for the decrease of thromboxane B2, instead, seems linked to a direct action of somatostatin, independently on the deranged metabolic conditions found in diabetic patients.