Decreased plasma prostacyclin-regenerating activities in diabetics

We assessed prostacyclin-regenerating activities (PGI2-RA) in 27 each of diabetic patients and of normal subjects by incubating plasma with "exhausted" rat aortic tissues, and compared these activities with platelet aggregability, vascular complications and the levels of fasting blood sugar (FBS) as an indicator of diabetic control. Patients' plasma showed a significantly decreased PGI2-RA when compared with normal (p less than 0.001). The activities in the patients with enhanced ADP-induced platelet aggregation in plasma or in whole blood were significantly decreased as compared with those with normal platelet functions (p less than 0.01). The patients with diabetic retinopathy showed significantly decreased PGI2-RA compared with those without this complication (p less than 0.02). A significant negative correlation was found between PGI2-RA and FBS levels before or during treatment. This abnormality found in patients' plasma appeared to be reversible and related to the degree of diabetic control. These results suggest that the decreased PGI2-RA could play a pathogenetic role together with platelet hyperaggregability in the development of microvascular and thrombotic complications in some diabetic patients.