Inhibition of multinucleation of cells treated with cytochalasin-B by cyclic dibutyryl-AMP.

Multinucleation of SV40-transformed mouse cells was induced by Cytochalasin-B as a result of inhibition of cytokinesis. Multinucleated cells with nuclei, whose number is other than that that can be obtained by raising the power of 2, were frequently observed. By simultaneous addition of Cytochalasin-B and cylic dibutyryl-AMP to SV40-transformad mouse cellls, multinucleation was fairly inhibited and the predominance of the cells with 2 or 4 nuclei was characteristic. In case of normal mouse cells (BALB/3T3), addition of both Cytochalasin-B and cyclic dibutyryl-AMP lessened the number of nucleic in a cell compared with treatment of the cells with Cytochalasin-B alone. These results suggested that cyclic dibutyryl-AMP inhibited multinucleation of cells treated with Cytochalasin-B and that the chemical regulated the division of nuclei in a cell to divide simultaneously.