The daily periodicity of the mitotic activity in the corneal epithelium of starving rats and mice

Summary

The author studied the 24 hour periodicity of mitotic activity in rats belonging to three different weight groups and mice during starvation. In heavy rats (250–260 g) and in those of moderate weight (150–160 g) starved for 2–5 days no statistically authentic differences were noted either in the 24 hour rhythm of mitosis, or in the mean 24 hour number of the latter (in comparison with control). Only in rats of low weight (50–60 g) and in mice the mitotic activity decreased considerably at the end of the experiment with prolonged starvation. However, the 24 hour rhythm of mitosis was retained to some extent. The 24 hour mitotic curves were characterized by a rise during the morning and reduction in the evening both in the animals on normal diet and in the starving ones.