It is generally recognized that the kidney is an important source of erythropoietin; but is it the only source?
Apparently so in the dog, but not in the rabbit or rat. Red blood cell formation, which is completely suppressed after nephrectomy in dogs, persists in the anephric rodents. What, then, is the role of the kidney in human erythropoiesis? Early studies on patients kept alive by dialysis after bilateral nephrectomy showed suppression of red cell formation followed by a return to normal only after renal transplantation. Thus, erythropoietically man appeared to be closer to his "best friend" than to the rodent. Subsequent reports, however, cast doubt on this conclusion. Nathan et al1 studied four patients maintained in the renoprival state for periods of 20 to 420 days. Reticulocyte percentage and plasma iron turnover gave evidence of erythropoietic activity in all four patients. But no erythropoietin was found in the
EXTRARENAL ERYTHROPOIETIN. JAMA. 1968;205(10):696. doi:10.1001/jama.1968.03140360056015