ALTERED LYSIS RESISTANCE OF PLATELET-RICH CLOTS IN PATIENTS WITH INSULIN-DEPENDENT DIABETES-MELLITUS

The fibrinolytic resistance of platelet-rich arterial thrombi received much attention. Clot lysis method was used to assess the in vitro fib rinolytic properties in diabetes mellitus. Platelet rich (PRP) clots w ere formed by addition of thrombin, and lysis was induced by tissue-pl asminogen-activator. The coagulation and lysis was followed by the lig ht scattering properties. A special pattern of good initial lysis foll owed by a second clotting phase was observed in more than half of insu lin dependent diabetic patients, while a similar pattern of clot-lysis was only occasionally found in non-insulin dependent diabetes mellitu s or in the healthy control group. Following the thrombin activation o f washed, gel-filtered platelets, the supernatants possessed an inhibi tory action on in vitro lysis of PPP-clots. This suppression was remar kably stronger in IDDM, along with the highest PAI-1 activity concentr ation ratio of the platelet lysates, compared to plasmatic levels. The relation of this special type of PRP clot-lysis resistance to diabeti c vascular complications needs further clarifying and investigations.