ADMA-D6 is intended for use as an internal standard for the quantification of NG,NG-dimethyl-L-arginine by GC- or LC-MS. ADMA (T7682) is an endogenous inhibitor of nitric oxide synthase (NOS). It is formed from arginine by protein arginine methyltransferases (PRMTs)and degraded by dimethylarginine dimethylaminohydrolases (DDAHs)and alanine-glyoxylate aminotransferase 2 (AGXT2). ADMA (T7682)levels are increased concomitant with an increase in blood pressure in Dahl salt-sensitive rats fed a high-salt diet. ADMA (T7682)levels are increased in the plasma in a variety of endothelial dysfunction-related diseases,including hypertension,congestive heart failure,and end-stage renal disease.