Suzuki M, Narnaware Y K, Baker B I, Levy A
School of Biology and Biochemistry, Bath University, UK.
J Neuroendocrinol. 1995 Apr;7(4):319-28. doi: 10.1111/j.1365-2826.1995.tb00764.x.
Melanin-concentrating hormone (MCH) gene expression in the brain of rainbow trout, reared and maintained in either pale or black-coloured tanks, was studied using in situ hybridization histochemistry. MCH transcripts were most prevalent in the magnocellular neurones of the nucleus lateralis tuberis (NLT), which project to the pituitary gland. They were also present, although at much lower levels, in dorsally projecting parvocellular neurones, sited more posteriorly above the lateral ventricular recess (LVR). In the NLT the most intense hybridization signal was seen over the pituitary stalk; above the LVR, the most active neurones were located caudally. In both the NLT and above the LVR, MCH hybridization signal was 4-fold stronger in white-reared fish than in black-reared fish. There was also a marked diurnal variation in MCH expression in both sites, with high levels at 16.00 h and lower levels at 04.00 h. The results show that gene activity in both hormonal (NLT) and neuromodulator/neurotransmitter (LVR) MCH neurones is induced by pale environmental colour and that MCH gene activity is subject to pronounced diurnal variation.
利用原位杂交组织化学技术，研究了饲养于浅色或黑色水箱中的虹鳟鱼大脑中黑色素浓缩激素（MCH）基因的表达情况。MCH转录本在结节外侧核（NLT）的大细胞神经元中最为普遍，这些神经元投射到垂体。在背侧投射的小细胞神经元中也有MCH转录本，这些神经元位于侧脑室隐窝（LVR）上方更靠后的位置，但其水平要低得多。在NLT中，垂体柄上可见最强的杂交信号；在LVR上方，最活跃的神经元位于尾部。在NLT和LVR上方，白色饲养的鱼的MCH杂交信号比黑色饲养的鱼强4倍。这两个部位的MCH表达也存在明显的昼夜变化，16:00时水平较高，04:00时水平较低。结果表明，浅色环境颜色可诱导激素型（NLT）和神经调节/神经递质型（LVR）MCH神经元中的基因活性，且MCH基因活性存在明显的昼夜变化。
