Possible oncostatic action of cysteamine on the pituitary glands of oestrogen-primed hyperprolactinaemic rats.
Cysteamine was investigated for its potential to reduce the size and secretion of oestrogen-primed hyperprolactinaemic rat pituitary glands. Subcutaneous administration of 80 and 120 mg cysteamine/kg significantly reduced plasma prolactin concentrations by 58 and 91% respectively, after 4h. Administration of cysteamine (60 mg s.c./kg body weight per day) for 10 days, to rats which had received an injection of 2 mg oestradiol benzoate on day 1, resulted in a significant reduction in pituitary mass (19%) and GH concentration (21%). Oral administration of 60 mg cysteamine/kg body weight to hyperprolactinaemic rats also produced a significant reduction in plasma prolactin of 94% after 2h. Oral administration of 60 mg cysteamine/kg body weight per day to rats for a 20-day period, during which they had received two injections of 2 mg oestradiol benzoate on day 1 and day 14 of treatment, resulted in a significant reduction in pituitary mass (29%) and the concentration of trunk blood prolactin concentration (35%). However, when oral cysteamine (60 mg cysteamine/kg body weight per day) was given for 20 days to rats which had been treated with 2 mg oestradiol benzoate once every 14 days over a 90-day period, it caused no change in pituitary weight, prolactin or GH concentration, or the concentration of prolactin in trunk blood.(ABSTRACT TRUNCATED AT 250 WORDS)
Jeitner
T M
TM
Department of Medicine, Flinders Medical Centre, Australia.
Oliver
J R
JR
D000818:Animals; D000970:Antineoplastic Agents; D001835:Body Weight / Q000187:drug effects; D003543:Cysteamine / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000031:analogs & derivatives; D013006:Growth Hormone / Q000032:analysis; D006966:Hyperprolactinemia / Q000097:blood* / Q000139:chemically induced / Q000188:drug therapy; D008081:Liposomes; D008297:Male; D009929:Organ Size / Q000187:drug effects; D010902:Pituitary Gland / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D011388:Prolactin / Q000032:analysis / Q000097:blood; D015175:Prolactinoma / Q000097:blood / Q000139:chemically induced / Q000188:drug therapy; D011863:Radioimmunoassay; D051381:Rats
D000970:Antineoplastic Agents; D008081:Liposomes; D004958:Estradiol; D003543:Cysteamine; D011388:Prolactin; D013006:Growth Hormone; C010452:estradiol-17 beta-benzoate