Effect of Oxalate on Turnover of Radioactive Phosphate by the Human Erythrocyte. ∗ † ‡

Abstract

Summary

When incubated with human blood, C-14 oxalate is distributed between cells and plasma with a significant preference for the cells. After incubation with inorganic P³² phosphate and oxalate, rate of loss of P³² from the erythrocytes suspended in buffered-normal saline was lower in the case of erythrocytes pre-incubated with oxalate, reaching a minimum value with 0.00075 molar oxalate. Inhibition of P³² loss from erythrocytes by oxalate was slightly enhanced by potassium but was reversed by calcium and magnesium ions in physiological concentrations. Concentration of the cellular organic phosphates of the acid-soluble ester fraction changes significantly after incubation of erythrocytes with inorganic P³² and oxalate. The changes caused by oxalate may in each case be attributed directly or indirectly to a reduction in available magnesium.

Acknowledgement is made to Professor A. Grollman for professional assistance and to Mildred Watkins and Mr. J. W. Jackson for technical aid.