Availability of endothelial von Willebrand factor and platelet function in diabetic patients infused with a vasopressin analogue.

Acute release of von Willebrand factor and its immunologically detected correspondent, factor VIII-related antigen, from the endothelial cells into the circulation was induced by an infusion of 1-deamino-8-D-arginine vasopressin in eight normal subjects and eight insulin-dependent diabetic patients. The patients had higher basal levels of von Willebrand factor (140 +/- 13%) and VIII-related antigen (112 +/- 18%) than the normal subjects (95 +/- 5% and 70 +/- 8%, respectively). 1-deamino-8-D-arginine vasopressin induced a two-fold rise of these levels in both groups, von Willebrand factor/VIII-related antigen remaining higher in the diabetic patients throughout the experiment. In the normal subjects, platelet retention in glass bead columns increased soon after the infusion but returned to basal values after 2 h. In the patients, it remained high at the end of the infusion. No changes in platelet aggregation occurred. These results suggest that increased plasma von Willebrand factor/VIII-related antigen in diabetic patients is accompanied by an increased endothelial content of this factor.