Chronic irradiation of rats: effect on bone marrow lipids

Male rats were exposed to chronic gamma irradiation with daily doses of 0.19 Gy for 120 days, 0.57 Gy for 90 days, 0.96 Gy for 35 days and with daily doses increasing from 0.55 to 2.74 Gy for 7 days. The composition of femoral bone marrow lipids was determined during and after exposure. A decrease in phospholipid concentration and an increase in the triacylglycerol concentration were found prevalent. A dose dependence of the onset and the extent of the changes were observed. The increase in the triacylglycerol concentration was caused by new adipocyte proliferation and persisted for a long time even after the adjustment of phospholipid concentration. An analysis of the bone marrow lipid composition may serve as a valuable indicator of the onset, extent and persistence of radiation injuries. (J.J.). 9 figs., 27 refs