Vasopressin analogues. Their role in disorders of hemostasis

At this time, when the acquired immunodeficiency syndrome, hepatitis, and other blood-borne diseases threaten patients, with bleeding disorders, who need treatment with blood products, it is rewarding to realize that a number of them can be safely and effectively treated through the stimulation of their own VIII:C and vWF production with desmopressin. Desmopressin is clinically useful for treatment of patients with moderate and mild hemophilia. The limits of the clinical indications are the nature of the bleeding episode, the resting factor level, the level that must be achieved, and the length of time the level must be maintained to manage any given bleeding episode. Desmopressin can be used more extensively to raise VIII:C in von Willebrand's disease, than in classic hemophilia, because fewer of the patients have the severe form of the disease that is unresponsive to desmopressin. VIII:C increases to about four times the resting values that can be expected in both hemophilia and von Willebrand's disease, but it must be kept in mind that the range of individual responses is large. Even though it is not easy to correct the prolonged bleeding time, particularly in patients with dysfunctional vWF, this drawback is of clinical importance for only a minority of cases. Use of desmopressin in acquired diseases of primary hemostasis has been proposed more recently, and our experience is more limited than for congenital bleeding disorders. Uremia is probably the most firmly established indication, because the bleeding time is often dramatically shortened by desmopressin, and hemorrhages can be stopped or prevented. The indications for the compound in liver cirrhosis and congenital and acquired platelet dysfunctions are promising but much less well-established. The mechanism of action of desmopressin is not well-known, and more work must be done to fill this important gap. This problem is not only of theoretical importance, because understanding of the mechanism of action of the compound should open up new perspectives into understanding the physiological mechanisms that regulate hemostasis. Many unclarified aspects of the mechanism of desmopressin action might be elucidated by using specific antagonists and also by using appropriate animal models. (Dogs and primates respond partially to desmopressin, but rats and rabbits do not respond at all).(ABSTRACT TRUNCATED AT 400 WORDS)