The Role of the Kidney in the Production of the Erythropoietic Factor

The role of the kidney in production of erythropoietin was investigated. Dogs were made anemic by phlebotomy and were then subjected to bilateral nephrectomy, ureter ligation or ureter section. Erythropoietic stimulating activity in the dog plasma was judged by measuring the incorporation of Fe⁵⁹ into the red cells of starved rats. No erythropoietic activity could be found in the dog plasma 24 and 48 hours after nephrectomy, but erythropoietic activity was found after ligation of the ureters.