The maturation of reticulocytes. I. Following introduction of reticulocytes into polycythemic and normocythemic animals.

Investigations were conducted on the life-span of "stress" reticulocytes and the fate of the early denucleated large-sized reticulocytes in circulating blood. Reticulocyte disappearance was examined after reticulocyte introduction into the vein and into the peritoneal cavity of polycythemic and normocythemic animals. The results indicated that these introduced reticulocytes matured to red cells by about 36 hours after injection under both the polycythemic and normocytehmic conditions. The large-sized reticulocytes disappeared by about 4 to 12 hours after introduction. The maturation of reticulocytes was largely arrested when the cells were introduced into the peritoneal cavity.