Long-term haemopoietic injury in mice after repeated irradiation: precursor-cell cycling and its regulation.
The cycling rate of haemopoietic stem cells (day 9 CFU-S) and granulocyte-macrophage colony forming cells (GM-CFC) in mouse femora was, in response to reduced numbers, elevated at all times of sampling between 3 weeks and 10 months after 4 repeated doses of 4.5 Gy X-rays (3 wk between doses). The level of a stimulator of CFU-S cycling was also elevated, and this was observed in both axial and marginal regions of the marrow inside the shaft. However, the rate of production of the stimulator was low; lower than previously reported in marrow regenerating after a single dose of 4.5 Gy, indicating damage to the regulatory stromal cells. The distribution of CFU-S across the axial and marginal zones of femoral marrow was changed from that in normal mice, where higher concentrations were found near the bone surface, to a more uniform distribution.
Tejero
C
C
Department of Experimental Haematology, Paterson Institute for Cancer Research, Manchester, U.K.
Lord
B I
BI
Mason
T M
TM
Hendry
J H
JH
D000818:Animals; D001853:Bone Marrow / Q000473:pathology / Q000528:radiation effects; D002453:Cell Cycle / Q000528:radiation effects*; D002455:Cell Division / Q000528:radiation effects; D003114:Colony-Forming Units Assay; D003470:Culture Media; D004307:Dose-Response Relationship, Radiation; D006410:Hematopoiesis / Q000528:radiation effects*; D006412:Hematopoietic Stem Cells / Q000473:pathology* / Q000528:radiation effects; D008297:Male; D051379:Mice
D003470:Culture Media