RESUMO
Three patients with probable congenital erythrocytosis were studied to determine the role of erythropoietin (ESF) in their disease. In addition, haemoglobin function was measured and ESF excretion determined in response to reduction in the haemoglobin concentration. In two cases ESF excretion was clearly elevated above normal, and in the third excretion was normal even at an elevated PCV. In all, phlebotomy of 15--20% of the blood volume led tomore than doubling in ESF excretion. This occurred in the presence of normal molecular haemoglobin function. Studies of the renal vasculature were normal. These results suggest a new form of congenital erythrocytosis associated with increased ESF production which is reciprocally related to the oxygen carrying capacity of the blood, but in the absence of any demonstrable abnormality in oxygen transport. These findings suggest an inherited defect, likely residing in the renal sensor responsible for the production of ESF. This defect is possible due to impaired recognition of available oxygen or else a decrease in oxygen supply at the subcellular level.
Assuntos
Eritropoetina/urina , Policitemia/congênito , Adolescente , Adulto , Criança , Feminino , Hematócrito , Humanos , Masculino , Oxigênio/sangue , Policitemia/sangue , Policitemia/urinaRESUMO
The plasma and serum of polycythemic animals and man are reported to exhibit erythropoietic inhibitory activity in certain bioassay systems. The plasmas of hypertransfused and normal sheep were fractionated by the methods of Cohn and Weimer and their associates, and the major fractions assayed for stimulatory or inhibitory activity in the exhypoxic polycythemic mouse assay system. The results indicate that the inhibitory activity acquired with hypertransfusion can be demonstrated in fraction VI of Cohn's and in precipitate of D of Weimer's methods and that the activity of each is retained in the eluates from G-200 Sephadex columns.