Effects of somatostatin on the behaviour of thromboxane B2 and beta-thromboglobulin in type I diabetes.

Pharmacological studies have shown that the addition of somatostatin to insulin promotes a more rapid recovery from diabetic ketoacidosis. However, contradictory results have been reported concerning the action of somatostatin on platelet function, frequently deranged in diabetes. Therefore the plasma levels of thromboxane B2, a stable metabolite of proaggregatory thromboxane A2 and of beta-thromboglobulin, a marker of platelet activation, were studied in 9 control subjects and in 13 insulin-dependent diabetic patients before and during somatostatin injection, administered as an initial 250 micrograms iv bolus followed by infusion of 300 micrograms over 3 h. In both groups, after somatostatin infusion thromboxane B2 and beta-thromboglobulin levels showed, respectively, a progressive fall and an increase up to the second hour. Over the next hour thromboxane B2 increased and beta-thromboglobulin decreased but their levels did not return to basal values. During this experiment beta-thromboglobulin plasma values in diabetic patients did not differ from those of control subjects. In contrast, thromboxane B2, decreased in relation to pharmacological treatment, maintained elevated levels. Our data, however, demonstrate that the dose of somatostatin used, produced in the diabetic patients a normal fall of thromboxane B2 in terms of percentage of base-line values, but increases of beta-thromboglobulin lower than in control subjects. It is suggested that platelet function should be evaluated when somatostatin is used in the treatment of poorly controlled type I diabetes.