Suppressive activity of acivicin on murine bone marrow hemopoietic progenitors.

Acivicin (AVC), a L-glutamine antagonist, is an intriguing antimetabolite coupling cell growth inhibition activity with differentiating effects. In this in vivo study the influence of acivicin on mice bone marrow hemopoietic progenitors was tested. 10 mg/kg b.w./day of acivicin were i.p. injected in B6D2F1 mice for nine days. Leucocyte and reticulocyte level (in peripheral blood), CFU-S (multipotent stem cells) and GM-CFU (granulocyte-macrophage committed progenitors) content in bone marrow were determined during drug administration and for 14 days thereafter. All tested populations decreased severely during the first days of treatment. The drop was particularly striking for bone marrow CFU-S. The recovery of hemopoietic progenitors, however, began while AVC was still administered. These results suggest that the effects of acivicin on normal mouse hemopoietic system are mainly inhibitory, causing considerable myelosuppression.