Uremic plasma after infusion of desmopressin (DDAVP) improves the interaction of normal platelets with vessel subendothelium.

Effects of 1-deamino-8-D-arginine vasopressin (DDAVP; 0.4 microgram/kg iv) were studied in 11 patients with uremia. Bleeding time, platelet retention on glass beads, factor VIII activities, plasma catecholamine levels, and studies on platelet interaction with the subendothelium were performed before, 1 hour after, and 6 hours after DDAVP infusion. Perfusates consisting of normal washed platelets, uremic platelet-poor plasma (u-PPP) and washed red blood cells were perfused through the Baumgartner perfusion system at a shear rate of 800 sec-1. One hour after DDAVP infusion, a shortening in the bleeding time and an increase in platelet retention on glass beads were noticed in these patients (p less than 0.01). Simultaneously, plasma levels of noradrenaline, factor VIII coagulant (FVIII:C), and von Willebrand factor (vWF) activities were statistically increased. Platelet deposition and platelet aggregate formation on subendothelium were consistently increased (p less than 0.05) in perfusions carried out with blood reconstituted with u-PPP obtained 1 hour after DDAVP. The "in vitro" addition of 1 U/ml vWF or 1 U/ml vWF plus 1 U/ml factor VIII to the pretreatment u-PPP had no significant influence on the parameters that quantify platelet-subendothelium interaction. However, after the addition of 10 ng/ml noradrenaline to a similar system containing basal u-PPP, a clear improvement (p less than 0.05) in platelet deposition was noticed. Our results confirm the hemostatic effectiveness of DDAVP in patients with uremia and reveal an increased platelet interaction with subendothelium mediated by a factor present in uremic plasma after DDAVP administration.(ABSTRACT TRUNCATED AT 250 WORDS)