Lactate dehydrogenase isoenzyme patterns in human foetal tissues during development.

The changes in lactate dehydrogenase isoenzyme fractions in various tissues from human foetuses were studied at different stages of development. The isoenzyme pattern changes with the gestation period. The adult pattern is attained at birth in heart, liver, muscle and kidney. Brain shows predominance of cathodic fractions even at birth, but becomes aerobic after 6-12 months. LDH1/LDH5 ratio shows a similar trend. It appears that the adult pattern of LDH isoenzymes consists of predominantly either the faster (aerobic tissues) or slower (anaerobic tissue moving isoenzymes resulting from a gradual shift during foetal and neonatal life.