[Determination of erythrocyte zinc by atomic absorption spectrophotometry: Its significance in iron deficiency anemia (author's transl)].

Present investigation was undertaken to elucidate the significance of changes in erythrocyte zinc levels in anemia. A preliminary study for the determination of erythrocyte zinc by atomic absorption spectrophotometry was done. The simple dilution method, in which zinc was determined directly from a sample of erythrocyte lysed and diluted with deionized water, appeared satisfactory in view of its rapidity, simplicity and accuracy. Of importance is that the temperature of sample and standard solution had to be matched. By using the above method, the mode of changes in erythrocyte zinc levels was investigated in healthy individuals and it was found that erythrocyte zinc expressed per gram of hemoglobin was inversely correlated to mean corpuscular hemoglobin concentration (MCHC). This relationship was also shown in patients with iron deficiency anemia and phlebotomy-induced anemia in rabbits. However, erythrocyte zinc expressed per milliliter of packed red cells was generally increased in these cases. The difference of erythrocyte zinc levels between 9:00 a.m. and 3:00 p.m. was not statistically significant. In addition, the levels of the B and of the C type erythrocyte carbonic anhydrases were assayed immunochemically. It was ascertained that there was a significant correlation between erythrocyte zinc levels and those of total carbonic anhydrase. This, the clinical importance of changes in erythrocyte zinc levels in anemia was discussed in relation to the role of this zinc - metalloenzyme.