Change of nuclear size in monolayer cells from embryonic mouse brain under the influence of cytosine-arabinoside.

The influence of cytosine-arabinoside (ara-C) on the nuclear size of monolayer cells from mouse brains were studied by quantitative analysis with the Quantimet (area measurement) and linear analysis with the Digiscan. Ara C (0,1; 1,0; 10,0 mug/ml) causes a significant nuclear enlargement, depending on the dose of 16%, 30% and 35% respectively and at the same time a decrease in cell density and an inhibition of mitotic activity. The size-distribution graph is altered by ara-C: the graph flattens and widens at the base. Moreover, in the case of 10,0 mug ara-C/ml a pronounced graph shoulder is visible in the small nuclear size region which can be interpreted as a slight accumulation of small nuclei. The nuclear enlargement is possibly due to an accumulation of shortchain polynucleotides.