[Accumulation of nonproliferating cells containing 4c DNA in stationary diploid cell cultures]

The cell proliferation was stimulated in stationary cultures of chick and human embryo cells by changing the medium. The cumulative indices of labeled cells and labeled mitosis as well as the cellular DNA contents were determined in the stimulated cultures at different times of growth until their entry into the stationary phase of growth. It is established that in the case of mass entry of cells into DNA synthesis period, part of them does not complete the mitotic cycle to be arrested in the G2-period. This arrest is considered as one of the ways of the cell proliferation inhibition in cultures entering into the stationary phase.