Extraction of Erythropoietin from Kidneys of Hypoxic and Phenylhydrazine-Treated Rats

Abstract

Abstract 1. Significant amounts of ESF have been extracted from kidneys of anemic and hypoxic rats by the use of hypotonic phosphate buffer at pH 6.8. 2. A minimum of 50 per cent of the ESF extracted from the kidneys was not due to activity contained in the trapped residual plasma. 3. Bioassay of sheep and rat plasma ESF and the kidney extracts by the radioiron-polycythemic mouse method indicated that the above preparations were parallel in their log-dose regressions, suggesting that these substances are similar in physiologic behavior.