Hematological modifications induced by estrogens in cirrhotic animals.

Estrogens are known to have mitogenic activities and to influence hematic crasis. A wide literature on this subject allows us to re-evaluate the results of research performed in 1950. Estrogens injected into the peritoneum (estradiol propionate 2.5-5 mg, twice weekly) or into tibial bone marrow (estradiol propionate 1.5 mg weekly) of guinea pigs, after carbon tetrachloride induced cirrhosis (CCI4 inhalation for 7-15 min twice weekly), caused hyperchromic anemia, with erythroblastosis and leucocytosis; hyperplasia of reticulo-hystiocitary cells of bone marrow and lymphoid organs; splenic hemosiderosis; hyperplasia of immature bone marrow cells, with maturative inhibition; and terminal bone marrow hypoplasia. Our results agree with recent literature data concerning the role played by natural estrogens and environmental xenoestrogens that are capable of stimulating bone marrow progenitor cell proliferation and delaying their maturation, by the secretion of growth factors, especially from hyperplastic stromal cells, in solid and hematological tumors.