Increased in vivo platelet activation and reduced intravascular endothelium-derived relaxing factor and nitrate/nitrite production in patients with insulin-dependent diabetes mellitus

Limited information seems to be available about the role of reduced endothelial production of endotheliumderived relaxing factor (EDRF)-nitrate/nitrite (NO) in the pathogenesis of diabetic angiopathy in insulindependent diabetes. A report of urinary and serum nitrate/nitrite, glucometabolic parameters, endothelial and in vivo platelet activation markers of 22 insulin dependent diabetics (IDDM) patients are given. Urinary and serum nitrate/nitrite concentrations were reduced in IDDM. This was independent of disease duration, presence of angiopathy and the glucometabolic parameters. A significant and inverse correlation of nitrate/nitrite excretion with endothelial markers (von Willebrand factor, soluble thrombomodulin) was documented. Moreover, reduced nitrate/nitrite excretion was strongly associated with elevated plasmatic beta -thromboglobulin levels. EDRF-NO production is reduced in IDDM and this reduction correlates with endothelial damage. Decreased nitrate/nitrite excretion may also influence in vivo platelet function, which results in increased in vivo platelet activation and suggests that the reduced intravascular production of EDRF-NO might play a role in the pathogenesis of angiopathy in IDDM.