The Development of the Red Pulp in the Spleen (Advances in Anatomy, Embryology and Cell Biology, 75)

Reviews and critical articles covering the entire field of normal anatomy (cytology, histology, cyto-and histochemistry, electron microscopy, macroscopy, experimental morphology and embryology and comparative anatomy) are published in Advances in Anatomy, Embryology and Cell Biology. Papers 'dealing with anthropology and clinical morphology that aim to encourage co-operation between anatomy and re' In many aspects hematopoiesis in newborn rodents, especially in rats, resembles hema topoiesis in the human fetus in the 6th-7th month of gestation. In man the transition from the stage of liver to bone marrow erythropoiesis takes place at this time (Bessis, 1973). In rodents, however, the liver is almost the only place where hematopoiesis occurs until birth. Thereafter it is replaced to a growing extent by the bone marrow, which so far consists mainly of immature mesenchymal cells (Maximow, 1910; Cuda, 1970). Thus hematopoietic precursor cells appear in the sternum only around 30 h after birth. Just as in premature human infants, a macrocytic anemia can be demonstrat ed in normal neonatal rats (Lucarelli et aI., 1964, 1968). Beside liver (fetal) and bone marrow, the spleen is involved in hematopoiesis. In rodents like rats and mice, splenic hematopoiesis persists more or less markedly until adulthood; in man, however, it ceases after birth and reappears only under certain pathological conditions (Fischer et aI., 1970; Hennekeuser et aI., 1967; Fresen, 1960) Front Matter....Pages N1-V Introduction....Pages 1-2 Autoradiography with 3 H-Thymidine ( 3 H-TdR)....Pages 2-5 Material and Methods....Pages 5-7 Cytology and Definition of the Rep Pulp Cells....Pages 7-14 Results....Pages 14-39 Discussion....Pages 40-57 Closing Remarks....Pages 57-58 Summary....Pages 59-60 Back Matter....Pages 61-71