Reticulocyte sequestration in spleens of normal, anaemic and leukaemic rats.

Abstract

Summary. Isolated spleens of normal, anaemic, and leukaemic rats were perfused with blood containing 2.7% reticulocytes collected from non‐bled rats and 12.1 and 22.4% reticulocytes collected from bled rats. From 2 to 11% of the reticulocytes in the blood were sequestered in the spleens, depending on (1) the level of reticulocytes in the blood, (2) whether the cells were macrocytic or normal‐sized reticulocytes, (3) the length of time of perfusion, and (4) the physiological condition of the spleen. The higher the reticulocyte percentage in the blood the greater the number of reticulocytes sequestered. A higher percentage of macrocytic reticulocytes was sequestered than normal‐sized reticulocytes. The longer the perfusion the greater the number of cells sequestered, the percentage of cells sequestered decreasing with time. No differences were observed between the sequestering capacity of spleens of normal and anaemic rats but the capacity of spleens of leukaemic rats was usually decreased. The results indicate that the rat spleen can sequester reticulocytes but that this capacity would not perceptibly influence blood reticulocyte levels in the intact animal.