抄録
The purpose of this paper was to study of the regulation of mechanism of erythropoiesis in polycythemia vera.
In polycythemic state (Hematocrit: 76%), plasma and urinary erythropoietin levels were virtually undetectable. On the other hand, the presence of an erythropoietin inhibitor was evidenced in the plasma from the patients with this disorder. Furthermore, polycythemia vera marrow showed no significant response to erythropoietin in vitro, while normal human marrow showed a markd increase of the incorporation of 3H-thymidine in erythroid cells when this hormone was added.
Lowering hematocrit by means of serial phlebotomies, the increase in erythropoietin excretion and reticulocytes were observed in polycythemia vera. Moreover, the increase of the in vitro incorporation of 3H-thymidine in erythroid cells was found in response to the severe anemia.
These observations indicate that two different controlling mechaisms of erythropoiesis in polycythemia vera are at work—the usual erythropoietin mechanism when the patient is at anemic levels and another more autonomous control as the red cell count reaches polycythemic values.
