AJP - Cell Physiology, Vol 235, Issue 5 251-C255, Copyright © 1978 by American Physiological Society
Electron probe microanalysis of red blood cells. II. Cation changes during maturation
R. G. Kirk, P. Lee and D. C. Tosteson
To understand the sequence of maturation of membrane transport and
hemoglobin production during erythropoiesis, we have measured the K, Na,
and Fe content in single mature red blood cells and bone marrow cells of
dog using electron probe microanalysis (EPMA). Mature red blood cells of
dog are low in potassium (LK) and high in sodium. These cells are derived
from erythroblastic stem cells, which are high in potassium (HK) and low in
sodium. This change from HK stem cells to LK red cells occurs in the
marrow. The ratio of K/Na was found to be less than 0.2 independent of
Fe/(K + Na) in circulating red cells. However, a significant number of
marrow cells had both low K/Na and low Fe/(K + Na). We conclude that the
changes in cation transport properties responsible for the conversion of HK
to LK cells occur before the synthesis of hemoglobin in at least some
marrow cells.
