INTERGENICULATE LEAFLET NEUROPEPTIDE Y MESSENGER RNA IN SYRIAN HAMSTERS

有两个主要的视觉输入到中央昼夜节律起搏器， 哺乳动物：从视网膜到起搏器的直接通路和间接通路 穿过外侧膝状体核的通路。本研究 项目涉及间接视束或膝状下丘脑束 (GHT)它投射到位于下丘脑的中央时钟。 GHT传达与环境照明水平有关的信息 中央时钟。此信息首先通过 视束至外侧膝状体的膝状体间小叶（IGL） 原子核神经肽Y（NPY）细胞体位于IGL内。这些 NPY细胞体投射纤维到位于视交叉上的时钟 下丘脑的核。对这些因素知之甚少 其调节IGL细胞体内的NPY合成。我们已经开始 研究大鼠脑内NPY mRNA合成的昼夜节律和光调节， 的GHT。 利用原位杂交组织化学技术，其他研究人员 最近已经证明在大鼠中存在编码NPY的mRNA 弓状核和皮质。去年我们用这些技术 叙利亚仓鼠IGL细胞附近的NPY mRNA。期间 明年我们将研究IGL内NPY mRNA的昼夜节律模式， 与下丘脑核团的模式，不接受视觉 投影此外，我们还将研究抗抑郁药的作用 药物在mRNA水平上的作用

There are two major visual inputs to the central circadian pacemaker of mammals: a direct pathway from the retina to the pacemaker and an indirect pathway which passes through the lateral geniculate nuclei. This research project concerns the indirect visual tract or geniculohypothalamic tract (GHT) which projects to the central clock located in the hypothalamus. The GHT conveys information pertaining to the level of ambient illumination to the central clock. This information is first transmitted through the optic tract to the intergeniculate leaflet (IGL) of the lateral geniculate nucleus. Neuropeptide Y (NPY) cell bodies are located within the IGL. These NPY cell bodies project fibers to the clock located in the suprachiasmatic nucleus of the hypothalamus. Very little is known regarding those factors that regulate NPY synthesis within cell bodies of the IGL. We have begun to investigate the circadian and light regulation of NPY mRNA synthesis within the GHT. Using in situ hybridization histochemical techniques, other investigators have recently demonstrated the presence of mRNA encoding for NPY in rat arcuate nuclei and cortex. Using these techniques last year we identified NPY mRNA in the vicinity of the IGL cells of Syrian hamsters. During the next year we will examine the circadian pattern of NPY mRNA within the IGL with the pattern in hypothalamic nuclei that do not receive a visual projection. In addition, we will investigate the effects of antidepressant drugs on the level of mRNA.