Kim Hyeon Yeong, Lee Chae Kwan, Lee Jong Tae, Moon Chan Seok, Ha Sung Chang, Kang Sung Goo, Kim Dae Hwan, Kim Hwi Dong, Ahn Jin Hong, Lee Sung-Bae, Kang Min-Gu
Chemical Safety and Health Research Center, Occupational Safety and Health Research Institute, Yuseong-Gu, Daejeon, Korea.
Neuroreport. 2009 Jan 7;20(1):69-73. doi: 10.1097/WNR.0b013e328315cd35.
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.
尽管已有研究表明，锰（Mn）可通过降低下丘脑多巴胺（DA）水平来增加催乳素（PRL），但锰诱导下丘脑 - 垂体 - 肾上腺轴调节的机制尚不清楚。我们评估了吸入锰对下丘脑多巴胺和垂体催乳素分泌的影响，并评估了垂体特异性转录因子1（Pit-1）（催乳素基因的转录因子）在锰诱导的大鼠脑内催乳素分泌变化中的作用。暴露于锰4周或13周（1.5毫克/立方米，每天6小时，每周5天）的雄性大鼠，下丘脑多巴胺水平呈进行性显著下降，而催乳素和Pit-1 mRNA水平则因锰暴露而升高。这些结果表明，暴露于锰会降低下丘脑多巴胺水平，并促进垂体中催乳素的分泌，且Pit-1可能是多巴胺和催乳素的调节因子。
