Influence of gonadotropin (FSH + LH) and thyrotropin (TSH) on the multiplication of Chinese hamster ovary (CHO) cells. Impact of the age of the culture.
CHO cells repeatedly treated with gonadotropin showed peak division rates after their third exposure and a decrease in the mitotic rate after their fourth exposure. Thyrotropin induced a considerable decrease in the mitotic rate following the first exposure, a significant increase after the second and a further decrease following the third and fourth exposures. The pattern did not differ between the two hormones when the cells were exposed further. The age (density of the cell cultures) had an appreciable influence on hormone-provoked changes in the mitotic rate, this differing only in intensity and never in the response following the initial re-exposure.
Csaba
G
G
Department of Biology, Semmelweis University of Medicine, Budapest, Hungary.
Török
O
O
D000818:Animals; D016466:CHO Cells / Q000166:cytology / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D016922:Cellular Senescence; D006224:Cricetinae; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006728:Hormones / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000494:pharmacology; D013972:Thyrotropin / Q000494:pharmacology
D006728:Hormones; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin