title: Role of erythropoietin and cyclic nucleotides in erythroid cell proliferation in fetal liver.
abstract: Cyclic AMP and cyclic GMP have been implicated as regulators of proliferation and differentiation in a variety of tissues including erythroid cells. Present studies indicate that erythropoietin is capable of stimulating an accumulation of cyclic GMP in fetal liver cultures. Erythropoietin (Ep) decreases the duration of the G1 phase of the cell cycle, diminishing the total cell cycle time by approximately 40%. In proliferating cells to which no Ep was added, concentrations of cyclic AMP and cyclic GMP changed as cells progressed through the cycle. Increases in cyclic GMP levels are associated with DNA synthesis and mitosis. On the other hand, cyclic AMP levels are associated with the G1 and G2 phases of the cycle. When Ep was included in cultures, the same cyclic nucleotide pattern relative to phases of the cell cycle was maintained. Thus, it is likely that cyclic GMP and cyclic AMP exert a regulatory influence on proliferation and differentiation of developing erythroid cells.
mesh_terms: D000818:Animals; D002453:Cell Cycle; D000242:Cyclic AMP / Q000494:pharmacology*; D006152:Cyclic GMP / Q000096:biosynthesis / Q000494:pharmacology*; D004247:DNA / Q000096:biosynthesis; D004920:Erythropoiesis; D004921:Erythropoietin / Q000502:physiology*; D005333:Fetus; D006418:Heme / Q000378:metabolism; D008099:Liver / Q000166:cytology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D004921:Erythropoietin; D006418:Heme; D004247:DNA; D000242:Cyclic AMP; D006152:Cyclic GMP