Open AccessRELATION BETWEEN THE CIRCADIAN RHYTHMS OF MITOTIC RATE AND CHOLESTEROL‐7α‐HYDROXYLASE ACTIVITY IN THE REGENERATING LIVER
Author(s) -
Van Cantfort Jacques J.,
Barbason Hervé R.
Publication year - 1972
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/j.1365-2184.1972.tb00371.x
Subject(s) - derepression , mitosis , circadian rhythm , biology , period (music) , mitotic index , endocrinology , cell division , medicine , rhythm , function (biology) , cholesterol , cell , gene , microbiology and biotechnology , biochemistry , gene expression , psychological repression , physics , acoustics
The evolution of mitoses and cholesterol‐7α‐hydroxylase activity were studied in parallel in the regenerating liver after a partial hepatectomy performed at two different hours of the nycthemeral period, i.e. 10 a.m. and 8 p.m. The mitotic index was used to assess the function of cell division while cholesterol‐7α‐hydroxylase activity was taken as a test of the tissue‐specific function. The results showed a different evolution of these two functions according to the time of the surgery. The data indicated that a mutually exclusive relationship took place between the function of cell‐division and the tissue‐specific function. These observations suggested that, during liver regeneration, the derepression of the genes coding the enzymes of these two different functions takes place in a complementary fashion, at two different phases of the nycthemeral period.