Used to measure DDAH (dimethylarginine dimethylaminohydrolase) enzyme activity in human biological samples such as plasma, serum, or tissue extracts. This assay helps in research related to nitric oxide metabolism, cardiovascular diseases, and endothelial dysfunction. By quantifying DDAH activity, researchers can assess the regulation of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase. Elevated ADMA levels are linked to hypertension, atherosclerosis, and chronic kidney disease, making this kit valuable in clinical and pharmaceutical studies focused on vascular health and metabolic disorders.