Ratio between the numbers of polyploid and binuclear liver cells during the 24-hour period

Summary

Experiments were staged on male albino rats weighing 150 gms. Animals were sacrificed at 11, 2, 5, 8, 11, 1 and 8 o'clock. Pieces of the left lobe of the liver were obtained for the examination. The number of binuclear and of the large polyploid (octoploid) cells were counted: the number of mitoses and destroying nuclei and their correlation at different time of the day was also estimated.

The greatest number of mitoses (1 per 1,000 cells) and of binuclear cells (38.8 per 1,000 cells) was noted at 2–5 A.M. At the same time the polyploid cell count decreased sharply. At 5 o'clock in the morning the number of binuclear cells reduced by one third, whereas the polyploid cell count reached the maximum. The number of destroying cells exhibited almost no change during the 24 hour period. Evidently, the restorative processes in the liver occur mainly at the expense of endomitosis, the specific weight of which is much greater than that of mitosis.