Early histogenesis in human embryonic liver

The present study reports the results of a light microscopy study on the early histogenesis of human liver. 18 human embryos in the age range of 6 to 10 gestational week were studied. The embryos were provided by the Department of Obstetrics and Gynecology following an abrasion in normal pregnancy. The embryonic liver was studied using conventional histologic technique, histochemical methods for lipids and glycogen detection: by enzyme chemical methods for establishing the activity of the enzymes lactatedehydrogenase (LDH) and succinatedehydrogenase (SDH). The hepatocytes and the basic five types of differentiating cells of mesenchymal origin of the liver were studied: hemopoietic cells, macrophages, endothelial cells, fibroblasts and smooth muscle fibres. Increased activity of the two dehydrogenases and an intensive reaction for glycogen in the hepatocytes and myoblasts were observed; for the other cell types the reaction was distinctly weaker. The obtained data could be associated with the changes in the metabolism of the differentiating cells at the beginning of the hepatoorganogenesis.