ERYTHROPOIESIS IN ANEPHRIC MAN.

Recent progress in the understanding of the physiology of erythropoiesis has led to definition of the kidney's importance as a source of erythropoietin. Although Erslev (1, 2) did not document erythropoietin production in rabbit kidney in vivo, Jacobson, Goldwasser, Fried, and Plzak (3), Reissmann, Nomura, Gunn, and Brosius (4), and Naets and Heuse (5, 6) clearly managed to define the kidney as an important regulator of erythropoiesis in rats and dogs. The studies in the dog were very convincing, for Naets (5) described nearly total and permanent erythroid aplasia after bilateral nephrectomy. Increasing ability to manage chronic renal failure and the renoprival state, by both renal transplantation and intermittent, long-term hemodialysis, has offered the opportunity to examine the possible role of the kidney in human erythropoiesis. Several uremic patients have undergone bilateral nephrectomy, remaining renoprival for from 2 to over 400 days before suitable homotransplantation could be performed. One individual, in whom a solitary kidney was accidentally removed, was subsequently transferred to the Peter Bent Brigham Hospital and studied before transplantation. In addition, erythropoiesis was measured in two patients who were considered for, but did not undergo, bilateral nephrectomy. The