[Proliferative activity in several tissues of unilaterally nephrectomized mice subjected to surgery at different times of the day].

Unilateral nephrectomy was performed in mice in the morning and in the evening. Mitotic activity in the proximal parts of the nephron tubules of the resting kidney and in the corneal epithelium was examined 48 and 60 hours after the operation. As compared with control, after the operation performed in the morning the mitotic index proved to increase 4.3 times and remained at a high level for 60 hours; after the operation performed in the evening mitotic index increased 9.3 times and decreased in 60 hours. It is concluded that the cells of the kidney epithelium entered into division more synchronously in the animals operated in the evening than in those operated in the morning. Nephrectomy had no influence on the level and rhythm of cell proliferation in the corneal epithelium.