The micronucleus test in rat erythrocytes from bone marrow, spleen and peripheral blood: the response to low doses of ionizing radiation, cyclophosphamide and vincristine determined by flow cytometry.

The frequency of micronucleated polychromatic erythrocytes (fMPCE) was determined in samples from bone marrow, spleen and peripheral blood of rats exposed to low doses of X-rays, cyclophosphamide or vincristine. The fMPCE values were lower in the peripheral blood than in bone marrow or spleen. This is due to the elimination of MPCE from the circulating blood, which was confirmed by the results from prolonged exposure of rats to gamma-radiation. When the analysis was restricted to the youngest PCE in peripheral blood, the sensitivity of the assay was considerably improved. This can be reproducibly achieved with the flow cytometric analysis. Copyright 1999 Elsevier Science B.V.