title: Effects of manganese exposure on dopamine and prolactin production in rat.
abstract: Although manganese (Mn) has been shown to increase prolactin (PRL) by decreasing dopamine (DA) in the hypothalamus, the mechanism of Mn-induced regulation of the hypothalamic-hypophyseal-pituitary axis is unclear. We assessed the effects of inhaled Mn on hypothalamic DA and pituitary PRL production and evaluated the role of pituitary-specific transacting factor 1 (Pit-1), a transacting factor of PRL gene, in Mn-induced changes in PRL secretion in the rat brain. Male rats exposed to Mn for 4 or 13 weeks (1.5 mg/m3, 6 h/day, 5 days/week) showed a progressive and significant decrease in hypothalamic DA, whereas PRL and Pit-1 mRNA levels increased in response to Mn exposure. These results suggest that exposure to Mn decreases hypothalamic DA and promotes the production of PRL in the pituitary and that Pit-1 might be a regulator of DA and PRL.
authors.affiliation: Chemical Safety and Health Research Center, Occupational Safety and Health Research Institute, Yuseong-Gu, Daejeon, Korea.
authors.forename: Hyeon Yeong
authors.initials: HY
authors.lastname: Kim
authors.forename: Chae Kwan
authors.initials: CK
authors.lastname: Lee
authors.forename: Jong Tae
authors.initials: JT
authors.lastname: Lee
authors.forename: Chan Seok
authors.initials: CS
authors.lastname: Moon
authors.forename: Sung Chang
authors.initials: SC
authors.lastname: Ha
authors.forename: Sung Goo
authors.initials: SG
authors.lastname: Kang
authors.forename: Dae Hwan
authors.initials: DH
authors.lastname: Kim
authors.forename: Hwi Dong
authors.initials: HD
authors.lastname: Kim
authors.forename: Jin Hong
authors.initials: JH
authors.lastname: Ahn
authors.forename: Sung-Bae
authors.initials: SB
authors.lastname: Lee
authors.forename: Min-Gu
authors.initials: MG
authors.lastname: Kang
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D002851:Chromatography, High Pressure Liquid; D004298:Dopamine / Q000032:analysis / Q000378:metabolism*; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism; D008297:Male; D017895:Manganese Compounds / Q000008:administration & dosage / Q000494:pharmacology*; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism; D011388:Prolactin / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D011916:Rats, Inbred F344; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013431:Sulfates / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors; D014131:Trace Elements / Q000008:administration & dosage / Q000494:pharmacology; D050817:Transcription Factor Pit-1 / Q000235:genetics / Q000378:metabolism
chemical_list: D017895:Manganese Compounds; D012333:RNA, Messenger; D013431:Sulfates; D014131:Trace Elements; D050817:Transcription Factor Pit-1; D011388:Prolactin; D004298:Dopamine; C039798:manganese sulfate