Detection of ferritin in the plasma of guinea pigs in experimental shock.

IT HAS BEEN proposed that the vasotoxic aspects of irreversible shock are due to the release of an iron-bearing protein, ferritin, into the circulation, and that the vasoinhibitory properties of ferritin, in turn, are due to the action of iron associated with this piotein. These impressions were gained, in the main, in experiments involving hemorrhagic shock. Recently, work in our laboratory has shown that increased levels of plasma-bound iron, although consistently present in hemorrhagic shock in rabbits and dogs, are not consistently encountered in several forms of normovolemic shock in these same species. In the majority of instances, plasma-bound iron levels were observed to decrease in animals in shock from nonhemorrhagic procedures, including shock induced by Escherichia coli endotoxin. On the basis of this observation, it was concluded that elevation in plasma-bound iron, although perhaps an important factor in hemorrhagic shock, is not necessarily directly involved in the pathogenesis of all forms of shock. In our previous experiments, no attempt was made to compare the levels of ferritin present in normovolemic shock with those present during hemorrhagie shock. Assays of total plasma-bound iron would not detect small amounts of fprritin-bound iron released into the circulation when transferrin-bound