Validity of Electrophoretic Determination of Lactic Dehydrogenase Isozymes

Abstract

ELECTROPHORETIC analysis of lactic dehydrogenase (LDH) generally indicates that most human tissues contain characteristic percentages of five different iso-zymes¹. However, when the same specimen of a tissue homogenate has been analysed under different electro-phoretic conditions, the results are not always consistent. Vesell, for example, has demonstrated that, during starch gel electrophoresis, the migration of isozyme 5 (numbering 1 from the anode) depends on its concentration². It has also been observed that the number and mobilities of isozymes may appear different after starch-gel electrophoresis than after agar electrophoresis^3,4. The causes of such apparent inconsistencies could be important in correctly interpreting electrophoretic results, and attempts have been made to investigate them. Studies so far indicate that, in the process of electrophoresis, isozymes may be subjected to interactions which entirely distort the true isozyme pattern.