الفهرس 
Diabetes MellitusOnly 14 pages are availabe for public view
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Abstract
Nitric oxide (NO) is a colourless gas synthetized and released by the endothelium of both arteries and veins and contributes to the control of basal and regional blood flow as an important modulator of vascular tone. NO is also formed in non-vascular tissues and cells as neurons in the brain,platelets and macrophages.It is noticed that the vascular endothelium has the key role in maintaining haemostasis of the vasculature through the synthesis of vasoactive substances that modulate vascular tone, inhibit platelet aggregation and vascular smooth muscle (VSM) proliferation. Endothelial dysfunction has been suggested to be an early event in diabetic vascular disease, and per se may initiate haemostatic abnormalities .Progression of diabetic nephropathy’is now associated with intrarenal hemodynamic disorders (renal hyperperfusion, hyperfiltration, intraglomerular hypertension). It is supposed that the endothelium derived relaxation factor [EDRF and endogenous NO] can cause these intrarenal hemodynamic alteration in diabetes mellitus. Also, it is reported that NO is responsible for increased blood flow in retinal vascular bed in early diabetes.Furthermore, NO inhibits thrombocyte aggregation and adhesion. So its decrease may contribute to an increased susceptibility to vasospasm, decrease inhibition of thrombus formation and an impaired ability to reduce vascular resistance in ischemic conditions. In diabetes mellitus, this impairment may be interpreted as an early marker of a process that ultimately will lead to atherosclerosis.