Counter-current distribution of red blood cells of slightly different ages.

Abstract

Abstract Rats were injected with [ 59 Fe]ferrous citrate and exsanguinated at different times after injection. This gave rise to red blood cell populations in which cells of distinct ages were radioactively labeled. Such red-cell populations were subjected to counter-current distribution in one of the aqueous, two-phase systems described by Albertsson . It was found that reticulocytes can be separated from mature young erythrocytes; young erythrocytes from old erythrocytes and further that erythrocytes differing in age by only a few days show distinct counter-current distribution patterns. The separability by counter-current distribution of red cells is due to a difference in their surface charge. The fact that red blood cells of slightly different ages can be separated from one another by this method is attributed to a continuous alteration of their surface charge during their life-span. It has also been shown that reticulocytes and mature young erythrocytes obtained by counter-current distribution have high, and older cells, low levels of glutamate-oxaloacetate transaminase (EC 2.6.1.1). Lactate dehydrogenase (EC 1.1.1.27) levels show a similar distribution but the quantitative difference between young and old cells is much smaller.