The Effect of Age on the Creatine in Red Cells

Abstract

SUMMARY The creatine in packed red cells was estimated by the diacetyl‐i‐naphthol technique. The error due to the presence of other guanidino compounds in the cells was found to be small. The mean value for creatine in the packed red cells of normal females was found to be 5.6 (S.D. ± 1.3) mg. per 100 ml., and in normal males 4.4 (S.D. ± 1.5) mg. per 100 ml. The sex difference is statistically significant. When red cells were segregated according to age by centrifugation the young red cells contained more creatine than the old cells. The creatine in the mixed population of red cells of patients under treatment for anaemia in whom there was increased erythropoiesis was greatly elevated; values as high as 50 mg. per 100 ml. were observed. With a decline in marrow activity and reticulocytosis there was a persistence of the high red‐cell creatine for a long time, suggesting that the loss of creatine from the cells with age is a gradual process. It is concluded that the level of creatine in the circulating red cells is a sensitive parameter of the mean age of the population.

Selective loss of calcium permeability on maturation of reticulocytes.

“…First, the Ca2-influtx correlates well with percentage of' reticuilocvtes ( Fig. 3) btut this flutx does not correlate with ervthrocyte creatine which reflects the ImleaIn cell age (13,20).…”

Evaluation of Intravascular Hemolysis With Erythrocyte Creatine in Patients With Aortic Stenosis

“…13,14) Because young erythrocytes contain higher erythrocyte creatine levels than older erythrocytes which decrease with advancing age, erythrocyte creatine is regarded as a reliable and quantitative marker to estimate the mean age of the erythrocyte. 8,9) In our earlier report, we measured erythrocyte creatine with other hemolytic markers to detect intravascular hemolysis in patients with a prosthetic valve and found that erythrocyte creatine was the most reliable marker to detect intravascular hemolysis. 4) Moreover, mild hemolysis was related to an increase in valvular flow velocity rather than valvular regurgitation.…”

“…In contrast, erythrocyte creatine is regarded as a sensitive and quantitative marker of mean age of the erythrocytes, because creatine contents in erythrocytes decrease gradually with advancing cell age and an increase in erythrocyte creatine quantitatively reflects the degree of shortened erythrocyte survival. [8][9][10] In our previous report, we measured erythrocyte creatine in patients with cardiac valve prostheses and found that erythrocyte creatine was a sensitive marker to detect intravascular hemolysis. 4) Intracardiac high velocity jets through stenosed or incompetent orifices can cause intravascular hemolysis, but few case reports have evaluated intravascular hemolysis in patients with native valvular heart disease.…”

Pseudoreticulocytosis in a Case of Myelodysplastic Syndrome

“…To support the hypothesis of a delay in reticulocyte maturation, Sher et al [4]were able to demonstrate that the red cell creatine content was only slightly increased in their patient. Since the red cell creatine content is inversely proportional to the age of red cells, a real increase in reticulocyte production should be associated with an increase in red cell creatine values [8]. …”