Protein Metabolism and Erythropoiesis. II. Erythropoietin Formation and Erythroid Responsiveness in Protein-deprived Rats

Abstract

(1) Rats on a normal and non-protein diet were hypertransfused to suppress their endogenous erythropoietin formation. Injection of erythropoietin elicited nearly identical increases in radioiron incorporation in the two dietary groups. (2) Normal and protein-starved rats were exposed to lowered atmospheric pressure. At each level of hypoxia the erythropoietin titer in the plasma of protein-starved rats were significantly lower than those in normal diet groups. (3) Re-proteinization resulted in significant increases in erythropoietin level. (4) It is concluded that protein deficiency does not affect cytoplasmic protein synthesis in erythroid precursors directly, and the depression of erythropoiesis is attributed to a diminished formation of erythropoietin.