Importance of Chemical Reduction in Plasma and Serum Homocysteine Analysis

Featured Article: Refsum H, Helland S, Ueland PM. Radioenzymic determination of homocysteine in plasma and urine. Clin Chem 1985;31:624–8.1In 1977, as part of the research on which I based my PhD thesis, I purified S-adenosylhomocysteine hydrolase to homogeneity, and in the years that followed, my colleagues and I studied its role in the metabolism of S-adenosylhomocysteine in cells and animals treated with adenosine analogs. During these experiments, we gained knowledge about the catalytic properties of the enzyme, which enabled us to construct an enzymic assay for homocysteine in rat and mouse tissues as well as in plasma from mice(1). When this methodological work was being carried out in 1982, data on homocysteine were sparse and addressed limited aspects of homocysteine in health and disease, such as homocyst(e)ine in patients with the inborn error of homocystinuria, increased homocyst(e)ine (often the homocysteine-cysteine mixed disulfide) in patients with cardiovascular disease …