Effects of danazol on proliferation and viability of 7,12-dimethylbenz(a)anthracene-induced mammary tumours in rats.
The suppressive effects of danazol, an isoxazol derivative of a synthetic steroid 17 alpha-ethinyltestosterone, on cellular viability and DNA synthesis in 7,12-dimethylbenz(a)anthracene induced mammary tumours were investigated in adult female rats by enzyme assays and immunohistochemistry with bromodeoxyuridine (BrdU). Rats treated with danazol for 30 days showed a decrease of plasma levels of luteinizing hormone and estradiol associated with a dysfunction in hypothalamo-hypophysial-gonadal axis, resulting in lower activities in succinate dehydrogenase and thymidine kinase, and a reduction of BrdU-immunoreactive cells in mammary tumours compared with the control, i.e., decreases of viability and pyrimidine nucleotide synthesis in tumour cells in danazol-treated rats.
Yoshimura
S
S
Medical Research Institute, Tokyo Medical and Dental University, Japan.
Sakamoto
S
S
Kudo
H
H
Suzuki
S
S
Sassa
S
S
Matsubara
M
M
Nagasawa
H
H
D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects*; D003338:Corpus Luteum / Q000187:drug effects / Q000502:physiology; D004273:DNA, Neoplasm / Q000096:biosynthesis; D003613:Danazol / Q000494:pharmacology*; D004958:Estradiol / Q000097:blood; D004971:Estrus / Q000187:drug effects; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000473:pathology*; D009929:Organ Size / Q000187:drug effects; D011388:Prolactin / Q000097:blood; D051381:Rats; D017207:Rats, Sprague-Dawley
D004273:DNA, Neoplasm; D004958:Estradiol; D015127:9,10-Dimethyl-1,2-benzanthracene; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D003613:Danazol