title: Relation of disease stage to humoral and cellular impairment of spleen reticuloendothelial system depression in a rat leukemia.
abstract: In the rat leukemia studied there is an early reversible depression of reticuloendothelial system (RES) function followed by a late-stage secondary depression, culminating in death, associated with an infiltration of leukemic cells into the bone marrow and spleen. In one set of experiments to assess RES function, isolated spleens of nonleukemic rats were perfused with blood from rats in progressively advanced stages of the leukemia. In a reciprocal set of experiments, isolated spleens of rats in comparable stages of the leukemia were perfused with blood from nonleukemic rats. The clearance of 99mTc-sulfur colloid from the blood perfusate was used as a test of RES function. In the first set, clearance was depressed in nonleukemic spleens perfused with blood collected from rats 1 hr after they had been inoculated with tumor cells, and it was more markedly depressed in a late stage of the leukemia 6 days later. Perfusion of nonleukemic spleens with blood from rats in intermediate stages of the leukemia did not depress clearance. In the reciprocal study, clearance was depressed in spleens of rats that were inoculated with tumor cells 1 hr before perfusion with nonleukemic blood. Clearance values were at the control level in spleens of rats in all other stages of the leukemia when calculated on the basis of total spleen weight. When calculated on a unit weight basis, clearance values were lower in the enlarged spleens of rats in advanced stages of the leukemia. The results indicate that impairment of RES clearance of 99mTc-sulfur colloid is associated with alternations in the humoral content of the blood of this leukemic rat. There is indirect evidence to suggest that in the terminal stage of the leukemia an impairment of splenic RES cells to clear 99mTc-sulfur colloid may develop secondarily.
mesh_terms: D000818:Animals; D001790:Blood Physiological Phenomena; D066298:In Vitro Techniques; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D012157:Mononuclear Phagocyte System / Q000378:metabolism / Q000503:physiopathology*; D010477:Perfusion; D051381:Rats; D013154:Spleen / Q000378:metabolism / Q000503:physiopathology* / Q000648:ultrastructure; D013455:Sulfur / Q000378:metabolism; D013667:Technetium; D013997:Time Factors
chemical_list: D013455:Sulfur; D013667:Technetium