Toshio Takai

Enzymatic Development of the Human Fetus; The Isozyme of Lactic Dehydrogenase in the Developing Human Fetal Tissues*

Studies on LDH‐isozyme during development of the human fetus were undertaken. In the heart and liver during the early fetal life, the activity was found to be predominant in the LDH‐3 area. In the heart the predominancy of LDH‐3 area was found to continue throughout the fetal life, while in the liver it decreased and LDH‐5 region increased at 5 months of gestation. A decrease in the activity of LDH‐3 in the heart was found to occur after birth. Changes in LDH isozyme pattern in the skeletal muscle were found to be approximate to those in the liver. No remarkable changes in the isozyme pattern were shown in the brain and kidney.

Enzymatic Development of Human Fetus; Studies on Cytochrome Oxidase and Succinic Dehydrogenase in Developing Human Fetus*

Activities of cytochrome oxidase and succinic dehydrogenase in the heart, liver and brain of the developing human fetus were determined.

Enzymatic Development of the Human Fetus: LDH/Aldolase Ratio in Developing Human Fetus

Studies on fructose diphosphate aldolase during development of the human fetus were undertaken. Additionally, the relation of the activity of LDH and its isozymes to aldolase in developing tissues including the liver, skeletal muscle, heart and brain were observed.

Enzymatic Development of the Human Fetus: Glucose-6-Phosphate Dehydrogenase in the Liver and Red Cells of the Human Fetus

The studies were undertaken to examine changes in glucose‐6‐phosphate dehydrogenase activity during development of human fetal liver and red cells. In the liver, high activity of glucose‐6‐phosphate dehydrogenase was observed through 6 months of gestation. Thereafter, the activity promptly decreased and remained in the range of the adult level. In the red cells, the highest level of enzyme activity was observed during the earliest fetal life. However, the activity of the enzyme in fetal liver was found to be about a thousand times greater than that of the fetal red cells. Accordingly, the high level of glucose‐6‐phosphate dehydrogenase activity in the human phosphate dehydrogenase activity in the human fetal liver may not be a consequence only of contamination by the erythrocyte enzyme.

Enzymatic development of the human fetus;The isozymes of glutamic oxaloacetic transaminase in developing human fetal tissues

Studies on GOT and its isozyme during development of the human fetus were undertaken.