Effect of Oxalate on the Activity of Lactate Dehydrogenase Isoenzymes

ELECTROPHORETICALLY separated lactate dehydrogenase isoenzymes differ from each other in several respects, including immunochemical specificity 1,2 , substrate affinities 3,4 ability to utilize coenzyme analogues 5 , sensitivity to inhibitors 6,7 , thermal stability 8 and substrate specificity 9 . Among the inhibitors which have been reported to exert different effects on the anodic and cathodic isoenzymes are sulphite, which preferentially inhibits the former 6 , and urea, which at certain concentrations inhibits the latter without much affecting the activity of the former 10,11 .