Dissecting the hematopoietic microenvironment. II. The kinetics of the erythron of the S1/S1d mouse and the dual nature of its anemia.

An analysis of the S1/S1d mouse for ferrokinetics and fate of peripheral red blood cells has shown the cause of its anemia to be dual in nature. While the S1/S1d produces red cells at a slightly greater rate than its normal littermate, its bone marrow and spleen appear to be operating near their maximal capacity and will reduce their output if anemic stress is partly relieved. The cause of the moderately high level of erythropoiesis in the S1/S1d is a mean daily loss of 2.5--3.0% of its total blood volume via the intestinal tract.