A Radiolabeled Assay for Aldose Reductase

A radiolabeled assay of aldose reductase has been developed based on the use of 14C-glyceraldehyde as substrate. The reaction is measured by the formation of 14C-glycerol, separation being effected by extraction with organic solvent. The Km value for glyceraldehyde has been estimated as 5.7 × 10−6 M. Inhibition by 2-oxoglutarate has been shown to be noncompetitive with a Ki value of 12.5 mM.