The development of the human fetal liver was studied with 68 cases from 5-week-old human embryo to 40-week-old human fetus to observe the development of the hepatocyte and hepatic cord, interrelation-ship between hepatic cord, hepatic sinusoid and erythropoiesis, appearing time of portal triad, and hepatic erythropoiesis.
The results obtained were as follows.
1. The_ liver by 5 weeks of gestation was composed of primitive hepatic cord, primitive sinusoid
and primitive central vein. Primitive hepatic lobules were seen by 6-8 weeks and the hepatic
cord became mature from 2-4 cell layers to one cell layer in thickness with age.
2. The portal vein and the bile duct were seen by 10 weeks and immature hepatic artery by 16
weeks, therefore, the portal triad was completed at 4 months.
3. Proerythroblasts and undifferentiated cells were seen and hepatic hemopoiesis began by 6 weeks.
The hepatic.hemopoiesis was mainly erythropoiesis and the erythropoietic activity increased greatly
during embryonic period, maintained the highest level at 3, 4, 5 months and decreased with age.
4. The relative areas of hepatic sinusoid during intrauterine life were high in early embryonic period,
low in mid term and slightly high in the last three motnhs in comparison with mid term.
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