COMPARATIVE HISTOCHEMICAL 



AND BIOCHEMICAL STUDIES 

 ON HEMOSIDERIN AND FERRITIN 



A. SHODEN and P. STURGEON 



Previous experiments from this laboratory demonstrated when large 

 amounts of iron were given to rabbits by the parenteral route, that the 

 quantities found by biochemical analysis in the form of soluble iron 

 (ferritin) and insoluble iron, vary 1) with the dose administered, 2) the 

 time interval from injection to analysis and 3) with the nature of the 

 compound administered. The insoluble iron granules which can be isolated 

 from tissue homogenates after preliminary water extraction of ferritin, 

 generally are assumed to be identical with the microscopically visible 

 granules which give a positive Prussian blue stain in histologie section; 

 both are commonly called hemosiderin. 



Comparative studies on hemosiderin estimated by thèse différent 

 methods hâve not been made. It was decided, therefore, to re-evaluate 

 with histochemical techniques in parallel with our biochemical methods, 

 the variables brought out in our previous experiments. 



Thèse studies show that iron injected as the saccharated oxide, even 

 in small amounts, resuit in a marked increase in the stainable iron of the 

 Kuppfer cells, while none appears in the parenchymal cells. With time, 

 the Kuppfer cell iron gradually decreases. Biochemically, this is asso- 

 ciated with a decrease in the insoluble and an increase in the soluble 

 fraction. With larger doses, as total ferritin iron exceeds 180 mg, further 

 increases in liver iron are reflected to a greater extent in the insoluble 

 them the soluble fraction. Kuppfer cell iron increases but little; however, 

 fine granules begin to appear in the parenchymal- cells; the increase in 

 thèse granules parallels that of the insoluble fraction. At thèse higher 

 levels, without further load but with time, there is, as at low levels, 

 a decrease in Kuppfer cell iron. However, in contrast to the changes 

 observed at low levels, there is a reciprocal increase in parenchymal 

 granules, but biochemically, there is no significant change in insoluble 

 or soluble iron. 



With iron dextran, stainable iron is not detected in either Kuppfer or 

 parenchymal cells until the total liver iron reaches 200 mg. Up to this 

 level, the quantity of insoluble iron is negligible; however, ferritin iron 



- 156 - 



