The induction of micronucleated polychromatic erythrocytes in mice using single and multiple treatments.

Studies are reviewed in which the effect of treatment/sample protocol on the induction of micronucleated polychromatic erythrocytes (MN-PCE) in male B6C3F1 mice by 3 carcinogens (benzidine, dimethylbenzanthracene and mitomycin C) were evaluated. 3 different treatment/sampling protocols were used, involving from 1 to 3 consecutive daily treatments and from 3 to 1, respectively, consecutive daily samplings beginning 24 h after the last injection. The results indicate that the 3-day injection/single sample time protocol eliminates the need for multiple sample times, minimizes the number of animals required in a study, decreases the time needed for data collection and simplifies data analysis. A comparison of the frequency of induced MN-PCE in peripheral blood and bone marrow suggests that, following a 3-injection protocol, either tissue can be used with equal efficiency.