1. Comparison of Asymmetric DimethylArginine Levels and Coronary Artery Calcifications in Different Stages of Chronic Kidney Disease and Kidney Transplantation Belda Dursun 1, Baki Yağcı 2, Aysun Toraman 1,Simin Rota 3 Pamukkale University, Medical School, Departments of 1 Nephrology, 2 Radiology,and 3 Biochemistry, Denizli, Turkey Introduction Abstract Category: Kidney Poster No: P794 Results Objectives Methods Conclusions References Dialysis patients had higher levels of ADMA and CACS compared to controls, pre- dialysis and transplantation patients. ADMA levels and CACS were comparable between kidney transplantation and predialysis patients. CACS levels showed positive correlations with age, serum creatinine, GFR, ALP, PTH, hs-CRP, ADMA and cIMT. ADMA levels showed positive correlations with P, Ca, Ca-P product, ALP, PTH, triglyceride, CIMT and negative correlation with HDL. Dialysis vintage was postively related to ADMA. CACS and hs-CRP. In conclusion, we suggest a linkage between ADMA and coronary artery calcifications in chronic kidney patients and kidney transplantation patients. ADMA may promote vascular calcifications through a deranged calcium-phosphate metabolism and the severity of hyperpratahyroidism and may serve as a new cardiac risk predictor in these groups of patients. Coronary artery calcifications are associated with cardiovascular events which is a major cause of death in CKD and kidney transplantation patients. Plasma asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is a potential cardiovascular risk factor. We conducted a study to determine an association between ADMA levels and coronary artery calcifications in pre-dialytic and dialytic stages of chronic kidney disesase and kidney transplantation. The study was performed on 38 pre-dialytic CKD (stage 3-5) patients, 39 chronic hemodialysis patients without diabetes, 44 kidney tranplantation patients and 46 non-uremic controls. None of the subjects had a previously documented cardiovascular history or revascularization. Plasma ADMA, hs-CRP, homocysteine, nitric oxide, Lipoprotein (a), HOMA- IR, Ca, P, PTH, alkaline phosphatase (ALP), cholesterol, albumin were determined in all subjects. Carotis intima-media thickness (cIMT) was measured by B- mode high resolution ultrasonography. Coronary artery calcification scores (CACS) were measured by multislice computed tomographytomography. 1. Moe SM et al. Role of calcification inhibitors in the pathogenesis of vascular calcification in chronic kidney disease (CKD). Kidney Int. 2005 Jun;67(6):2295-304.Kidney Int. 2. Coen G et al. Asymmetric dimethylarginine, vascular calcifications and parathyroid hormone serum levels in hemodialysis patients. J Nephrol. 2009 Sep-Oct;22(5):616-22.J Nephrol. 3. Mazzaferro S et al. Serum levels of calcification inhibition proteins and coronary artery calcium score: comparison betweentransplantation and dialysis. Am J Nephrol. 2007;27(1):75-83.Am J Nephrol. Cardiovascular disease is the leading cause of death in patients with chronic kidney disease (CKD) as well as kidney transplantation. Coronary artery calcifications are associated with cardiac disease. Pathophysiology of vascular calcifications in CKD is complex due to multiple traditional and non-traditional risk factors. Plasma asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is a potential cardiovascular risk factor. Increased ADMA levels lead to endothelial dysfunction and oxidative stress. ADMA accumulates in renal failure due to defective inactivation and excretion. The impact of kidney transplantation on ADMA levels is not clear.