[Effect of a hemolysate from polycythemic animals on proliferation on bone marrow cells]

Erythrocytic inhibitor from the polycythemic rats depressed the mitotic activity of the cells of the erythroid series in mice by 40%. The inhibitory effect lasted about 12 hours. The inhibitor acted on the G2-period. Not only the blast forms of the erythron, but also the stem hemopoietic cells served as the points of the inhibitor "application".