Diurnal rhythm of mitosis and in number of DNA-synthesizing cells after adrenalectomy in mice

Abstract

Diurnal changes in the number of DNA-synthesizing cells and in the number of mitoses were studied in the corneal epithelium and liver of intact and adrenalectomized mice. The curve of diurnal changes in the number of labeled nuclei in the corneal epithelium of the mice after adrenalectomy became bimodal and the amplitude of fluctuations in the mitotic index in the course of the 24-h period increased sharply compared with the control. The rhythm of DNA synthesis in the liver was similar in the control and experimental series, and the rhythm of mitosis in the experimental animals became biphasic in character. Adrenalectomy thus disturbs the phase structure of the rhythms of DNA synthesis and of mitosis in the tissues studied.