Studies on reticuloendothelial system and hemaotpoiesis. I. Studies of extramedullary hematopoiesis

The author studied the hematopoietic disturbances of rabbit induced by saponin injection and drew the following conclusions: 1) By saponin injection, the structure of bone marrow is disintegrated and hematopoietic cells are released into the circulating blood forming extramedullary hematopietic foci mainly in liver and spleen. The main attacking point of saponin should be RES. Recovery of hematopoietic foci is associated with the recovery of RES. The most marked extramedullary hematopoiesis is found three days after the injection. Thereafter, bone-marrow hematopoiesis proceeds to recovery stage, during which hematopoietic foci in liver and spleen are preserved, especially those in spleen persist fairly for a long time. 2) Daily injections of India ink kept up over a long period of time after the treatment with saponin, prevent the recovery of anemia and bone-marrow hematopoiesis. The lymph nodes, whose RES escaped from the severe damage by India ink, keep the hematopoietic foci for a long time. 3) As far as hematopoiesis is concerned, there seems to be no functional differentiation among RE cells, though they seem to have a special function according to the organs to which they belong, e. g. antibody formation in lymph apparatus, hematopoiesis in bone marrow and red cell destruction in spleen.</p

Studies on reticuloendothelial system and hematopoiesis. II. A study on the morphology and function of erythroblastic islet

1. For the purpose to clarify the role of reticuloendothelial cells in the center of erythroblastic islet, the medullary and extramedullary erythropoietic foci in convalescence of phenylhydrazine arternia were observed by light and electron microscopies, and the mode of development of anemia in rabbit having blocked RES. 2. Light microscopic observations revealed the stimulated formation of erythroblastic islet in phenylhydrazine anemia. Electron microscopic observations revealed the rhopheocytotic vesicles in the membrane of erythroblast, some of which contained ferritin particles. 3. Repeated India ink injections induced anemia with RES damage by being heavily laden with soot particles. Color index of these animals was not reduced to the state of hypochromic anemia. Anemia is due to the damage of erythroidcell reproduction, but not due to the disturbed hemoglobin metabolism by the inhibited iron uptake. 4. From the results obtained the author concludes that the role of reticuloendothelial cell in islet is not to transfer ferritin to erythroblast but the reproduction of erythroid cells.</p

Histo-chemical and cytochemical studies on the succinic dehydroge-nase system with three ditetrazolium salts, NT, Nitro-NT, and Nitro-Bt

1. Histochemical and cytochemical studies with respect to the sites of reaction were made on the succinic dehydrogenase system activity of human and animal tissues using ditetrazolium salts, namely, neotetrazolium chloride, nitro-neotetrazolium chloride, and nitra-blue tetrazolium chloride. 2. The advantages and disadvantages of each ditetrazolium salt for histochemical and cytochemical purposes and the reaction taking place in frozen tissue sections and that in fresh tissue blocks were compared, and the method of procedure suitable for each condition was established with some modification. 3. Selecting conditions suitable for cytochemical purpose, it was shown that the reaction took place at the sites coinciding with mitochondria, and the distribution of the enzyme reaction was also examined. In addition, several new findings in the brains and other tissues cytochemically made clear were pointed out.</p