Abstract
Diabetic retinopathy often progresses after rapid blood sugar control in patients with long-standing diabetes. We investigated the changes that occurred in diabetic patients who achieved blood sugar control from the standpoint of platelet aggregation and arachidonate cascade. Platelet aggregation induced by ADP, collagen, PAF or epinephrine, plasma TXB2 (TXB2) and 6-keto-PGF1 α(PG), the ability of platelets to produce TXB2 during spontaneous clotting, and blood viscosity, were measured pre-treatment and about 3 weeks and 6 weeks after blood sugar control in 19 diabetic patients.
Platelet aggregation induced by each agonist and plasma TXB2 increased at 3 weeks but returned to the previous level at 6 weeks after blood sugar control. Plasma PG gradually increased and the plasma TXB2/PG ratio decreased gradually after blood sugar control. Blood viscosity also decreased gradually after blood sugar control. There was a correlationship between the increase in plasma TXB2 and the decrease in HbA1 level at 3 weeks after blood sugar control. It is suspected that the increase in platelet aggregation and plasma TX may have an influence on the deterioration of retinopathy after blood sugar control.
