PROJECT 4: SEROTONIN RELATED TRANSCRIPTION FACTORS IN ANIMAL MODELS - DEPRESSION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 5-羟色胺能系统的失调和下丘脑-垂体-肾上腺(HPA)轴的异常被认为在抑郁症的病理生理学中起作用。在脆弱的个体中，压力往往被视为抑郁的常见诱因。慢性应激后对HPA轴的过度刺激会导致皮质醇的过度分泌，这是许多抑郁症患者常见的情况。抑郁症患者循环皮质醇水平的正常化被发现与临床治疗的成功相关。压力和不良生活事件与抑郁症的病因有关，女性患抑郁症的可能性是男性的三倍，这支持了这样一个事实，即女性患抑郁症的可能性是男性的两倍。5-羟色胺(5-羟色胺)系统似乎在抑郁症的病因和抗抑郁药物治疗的反应中起着重要作用。经典和新近的抗抑郁药物似乎都能调节5-羟色胺的神经传递。 这一应用的中心假设是，应激诱导的5-羟色胺相关转录因子(NUDR、Freud-1和Pet-1)的变化在调节几个5-羟色胺特异基因方面发挥着重要作用，这些基因控制着应激暴露后5-羟色胺的生物合成和神经传递。这一假说将通过以下具体目标进行评估：目的1.确定慢性束缚应激下雄性大鼠中缝背叶和前额叶皮质5-羟色胺相关转录因子生物合成的特异性变化。目的2.研究束缚应激对雌性大鼠中缝背叶和前额叶皮质5-羟色胺相关转录因子生物合成的影响。目的3.研究抗抑郁治疗对慢性束缚应激大鼠Pet-1、Freud-1和NUDR表达的影响。 我们的长期目标是阐明压力和性别差异如何调节5-羟色胺特异转录因子的表达，以及这些转录因子如何反过来调节5-HT1-A受体、色氨酸羟化酶2(TPH2)和5-羟色胺转运体(5-HTT)的基因，作为开发新疗法的必要前提。本研究将利用多种生化和分子生物学方法，包括原位杂交、Western blotting、实时荧光聚合酶链式反应(Real Time PCR)和cDNA合成，对大鼠中脑中缝背核和前额叶皮质脑组织中各种5-羟色胺能分子和转录因子的蛋白和基因表达进行定量研究。这项提议将是第一次研究这些新的5-羟色胺相关转录因子在与抑郁相关的应激动物模型中的表达。总之，这项拟议的研究将阐明应激诱导调节5-羟色胺相关转录因子和5-羟色胺神经传递的分子机制，并可能导致发现治疗应激相关抑郁和精神疾病的新靶点。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Dysregulation of the serotonergic system and abnormalities of the hypothalamic-pituitary-adrenal (HPA) axis have been suggested to play a role in the pathophysiology of major depression. Often stress is seen as a common precipitant of depression in vulnerable individuals. Excessive stimulation of the HPA axis following chronic stress results in the hypersecretion of cortisol, a common condition seen in many depressed patients. Normalization of circulating cortisol levels in depressed patients has been found to correlate with successful clinical treatment. Stress and adverse life events have been implicated in the etiology of depression and women are three times more likely than men to develop depression in relation to stressful life events, supporting the fact that women are twice as likely to suffer an episode of depression compared to men. The serotonin (5-HT) system appears to play a major role in the etiology of major depression and the response to antidepressant treatment. Classical as well as more recent antidepressant drugs appear to modulate 5-HT neurotransmission. The central hypothesis of this application is that stress-induced changes in serotonin-related transcription factors (NUDR, Freud-1 and Pet-1) play a significant role in regulating several serotonin-specific genes that control serotonin biosynthesis and neurotransmission following stress exposure. This hypothesis will be evaluated through the following specific aims: Aim 1. Determine specific alterations in the biosynthesis of the serotonin-related transcription factors in the dorsal raphe and prefrontal cortex of male rats exposed to chronic restraint stress. Aim 2. Determine specific alterations in the biosynthesis of serotonin-related transcription factors in the dorsal raphe and prefrontal cortex of female rats exposed to restraint stress. Aim 3. Study the effects of antidepressant treatment on the expression of Pet-1, Freud-1 and NUDR in male and female rats exposed to chronic restraint stress. Our long-term objectives are to elucidate how stress and gender differences modulate the expression of serotonin specific transcription factors and how these in turn regulate genes for the 5-HT1-A receptor, tryptophan hydroxylase 2 (TPH2) and the 5-HT transporter (5-HTT) as a necessary prerequisite to the development of novel therapeutics. The studies will utilize several biochemical and molecular biological procedures including in situ hybridization, Western blotting, real time PCR and cDNA synthesis to quantify protein and gene expression of the various serotonergic molecules and transcription factors in rat brain tissues from the midbrain dorsal raphe nucleus and prefrontal cortex. This proposal will be the first study to examine the expression of these novel serotonin-related transcription factors in an animal model of stress related to depression. Overall, the proposed research will elucidate the molecular mechanisms involved in the stress induced regulation of serotonin-related transcription factors and serotonin neurotransmission and may lead to the discovery of novel targets for the treatment of stress related depression and psychiatric illness.