Quantitative characteristics of phagocytic organs

Abstract Organ and tissue phagocytosis of intravenously injected cobaltic oxide was studied quantitatively over a wide range of dose levels by means of radioassay of Co260O3 in rats. There is a single linear relationship between the amount of particulate administered and the amount recovered from liver, spleen, and lung combined. The same is true for the uptake by the liver alone. However, the spleen and lung each has two linear relationships. For the spleen the two different linear trends are related to the dose administered, while for the lung the determining parameter is the weight and (or) age of the animal. Notwithstanding these different linear trends, the uptake by spleen and lung is interdependent. Although the liver is the main phagocytic organ, per unit weight the phagocytic uptake of the spleen exceeds that of the liver at amounts of cobaltic oxide larger than 40 mg. The reverse is true for amounts less than or equal to 40 mg. The phagocytic uptake by other components of the RES was not sufficient for reliable quantitative estimation.