Oestrogen-induced renal carcinogenesis in the hamster: ultrastructural and hormonal studies of the pars intermedia before and after withdrawal of oestrogen.
Long-term oestrogen treatment of male hamster induced renal carcinoma and pituitary enlargement due to hypertrophic and hyperplastic change in the pars intermedia. The latter effect was accompanied by ultrastructural abnormalities in pars intermedia cells and elevation of serum MSH concentration. Oestrogen treatment was stopped after 36 weeks and animals were killed at intervals from 8 to 36 weeks after oestrogen withdrawal. Nearly complete tumour regression occurred during the 36 weeks following cessation of oestrogen and by 28...36 weeks the pars intermedia cells regained normal ultrastructural appearance. However, pituitary enlargement and elevated serum MSH levels persisted throughout the post oestrogen recovery period.
D000818:Animals; D006224:Cricetinae; D004054:Diethylstilbestrol / Q000494:pharmacology*; D007279:Injections, Subcutaneous; D007680:Kidney Neoplasms / Q000139:chemically induced* / Q000648:ultrastructure; D008297:Male; D009074:Melanocyte-Stimulating Hormones / Q000097:blood; D008647:Mesocricetus; D009929:Organ Size / Q000187:drug effects; D009940:Organoids / Q000648:ultrastructure; D010902:Pituitary Gland / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism
D004054:Diethylstilbestrol; D009074:Melanocyte-Stimulating Hormones