Peptide Receptor Systems

肽受体系统

基本信息

批准号：
9357264
负责人：
Ted B Usdin
金额：
$ 110.11万
依托单位：
NATIONAL INSTITUTE OF MENTAL HEALTH
依托单位国家：
美国
项目类别：
财政年份：
资助国家：
美国
起止时间：
至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/9357264
关键词：
Ablation Acute Pain Adult Affect Aggressive behavior Amygdaloid structure Animals Anxiety Area Aversive Stimulus Behavior Behavioral Biochemical Biological Brain Brain Stem Brain region California Cell Nucleus Cells Cognitive Corticotropin-Releasing Hormone Data Drug usage Emotional Emotions Environment Event Excision FOS gene Freezing Fright Gene Mutation Genes Glutamates Goals Half-Life Hippocampus (Brain)Human Hypothalamic structure Impairment Intervention Investigation Knockout Mice Knowledge Laboratories Lead Link Location Maps Maternal Behavior Measures Medial Memory Mental Depression Mental disorders Modeling Molecular Target Mood Disorders Moods Mus Nerve Neurons Neuropathy Neuropeptides Neurosecretory Systems Nociception Pain Parathyroid Hormone Receptor 2 Pathway interactions Pattern Peptide Receptor Peptides Pharmaceutical Preparations Pharmacogenetics Pharmacotherapy Phenotype Physiological Play Population Post-Traumatic Stress Disorders Process Psychotropic Drugs Regulation Reporting Resolution Rodent Role Sensory Shock Signal Transduction Site Skin Spinal cord posterior horn Stimulus Stress Swimming Symptoms System Tactile Testing Thalamic structure Time Treatment Efficacy Universities Virus Work activity marker adult neurogenesis alcohol effect allodynia anxiety-like behavior base behavioral response chronic pain design designer receptors exclusively activated by designer drugs diphtheria toxin receptor environmental change fast-acting neurotransmitter fear memory foot gene function hormone regulation insight keratinocyte locus ceruleus structure male neurochemistry neurogenesis neuroregulation noradrenergic novel object recognition painful neuropathy performance tests prevent receptor recombinase reduce symptoms research study resilience response sciatic nerve sensory input sensory stimulus social stressor targeted delivery therapeutic target transmission process traumatic event

项目摘要

Following discovery of the neuropeptide Tuberoinfundibular Peptide of 39 residues (TIP39) and its receptor, the Parathyroid Hormone Receptor 2 (PTH2R) the section focused on investigation of their biological roles. Neuroanatomical mapping showed synthesis of TIP39 in discrete neuronal groups in the thalamus and brainstem that project to brain areas involved in emotional function. Following its anatomical mapping, laboratory projects turned to investigation of hypotheses derived from the distribution of the PTH2R/TIP39 system. Findings include that TIP39 modulates activation of hypothalamic neuroendocrine neurons including that it is important for an appropriate homeostatic response to cold. These studies lead to a general model for TIP39 action, that activation of PTH2Rs may be necessary for robust and sufficient excitatory transmitter release under high demand conditions. TIP39 was also found to modulate both acute pain sensitivity, and the return to normal sensitivity in chronic pain models. The latter effect appears to involve the locus coeruleus, a brainstem nucleus that contains noradrenergic neurons with modulatory influence throughout the CNS. In combination with other observations this suggests that TIP39 may be one of the modulators involved in the relationship between sensory stimuli and mood. Difficulty distinguishing between effects of ongoing aversive sensory input and its long-term consequences is a significant roadblock to investigating relationships between sensory stimuli and mood. To overcome this limitation we developed a paradigm to compare cellular and behavioral changes during and after reversing neuropathic pain in mice. Tactile allodynia and neuronal activation in the spinal cord dorsal horn produced by a cuff placed around the sciatic nerve resolved within several days following cuff removal. In contrast, changes in elevated O-maze, forced-swim, Y-maze spontaneous alternation and novel-object recognition test performance that developed after nerve cuff placement persisted at least 3 weeks after nerve cuffs were removed. Thus anxiety- and depression-like behaviors persisted following apparent resolution of pain in this paradigm. One contemporary idea regarding the cellular changes underlying depression is that inhibition of normal adult neurogenesis plays a role. Adult hippocampal neurogenesis is inhibited in chronic pain models, suggesting that neurogenesis inhibition may be involved in chronic pain associated depression. Using the reversible neuropathic model we found that adult hippocampal neurogenesis was decreased for at least 3 weeks following pain resolution. Also, FosB, a neuronal activity marker with a long half-life, remained elevated in the basolateral amygdala of mice with resolved nociception and persisting behavioral effects. Thus the reversible neuropathic paradigm points to specific cellular phenotypes that can be used to elucidate links between nociceptive sensory signaling and mood disorders. Previously, we found that mice with inactivating mutations of the genes encoding TIP39 (TIP39-KO) or the PTH2R (PTH2R-KO) have increased anxiety-like behavior under stressful conditions, relative to wild-type. Mice without TIP39 signaling have increased stress-dependent impairment in tests of memory function. Dysfunctional responses to stress are widely thought to contribute to depression, implying that this neuropeptide system plays a role in normal resilience. We investigated TIP39/PTH2R contributions to long-term fear memory using a model of post-traumatic stress disorder (PTSD) in which mice are exposed to a single aversive stimulus (foot-shock), after which fear memory is evaluated by measuring the time spent motionless (freezing, a rodent fear-like response) when the animals are re-exposed to the specific environment (fear context) in which the stimulus was delivered. While absence of TIP39 signaling did not cause a detectable change in fear memory 1 week after shock, both TIP39-KO and PTH2R-KO mice had increased fear-like behavior in the fear context after 2 and 4 weeks. Increasing in fear memory over time following a fear-inducing event is called fear incubation. Based on similarity to delayed symptom onset that frequently occurs in PTSD, fear incubation is used to investigate mechanisms that may contribute to PTSD. Thus, we investigated the neuroanatomical basis for enhanced fear incubation in mice that lack TIP39 signaling. Comparing neuronal activation patterns between mice with and without TIP39 signaling, either immediately after foot-shock or 4 weeks later when animals were returned to the fear context, revealed that TIP39 signaling absense prevented the normal activation of c-Fos in the medial nucleus of the amygdala (MeA). We used a PTH2R antagonist and mice that express Cre-recombinase in neurons that normally contain PTH2Rs, which we previously developed, to investigate whether the TIP39/PTH2R system in the MeA is responsible for the enhanced fear incubation. MeA targeted delivery of a virus encoded PTH2R antagonist reproduced the enhanced fear incubation of the KO mice. Selective ablation of MeA neurons that normally synthesize PTH2Rs following stereotaxic delivery of a virus Cre-dependently encoding a diphtheria toxin receptor also led to enhanced fear incubation. Transient inhibition of MeA PTH2R expressing neurons using a virally delivered Cre-recombinase dependent Designer Receptor Exclusively Activated by Designer Drugs (DREADD), starting just before or just after foot-shock, or at the time of recall testing 1 month later showed that inhibiting PTH2R neurons near the time of the event but not at the time of recall testing caused enhanced fear incubation. Putting these observations together, these experiments showed for the first time that the state of the medial nucleus of the amygdala just after a traumatic event has a major effect on fear-like behavior a month later. It further shows that signaling by a neuropeptide can have a major effect on that state. Ongoing work examines contributions of TIP39 signaling in the medial nucleus of the amygdala to other behaviors. Based on decreased inter-male aggressive behavior and increased social investigative behavior by PTH2R-KO mice, and similar effects following pharmacogenetic inhibition of medial amygdalar PTH2R expressing neurons the system appears to play a significant role in selection of social responses. Several previous studies provide evidence that that TIP39 signaling influences maternal behavior. Work with Arpad Dobolyi (Etvs Lornd University) during this reporting period provided anatomical evidence that TIP39 neurons in the thalamic subparafascicular area relay suckling related information to the hypothalamus to affect maternal behaviors. New work with Richard Gallo (University of California San Diego) showed that both TIP39 and the PTH2R are expressed at high levels in populations of cells within the skin, and implied that the system regulates keratinocyte function. Danny Winder (Vanderbilt University) used a virus we made that Cre-dependently expresses the human diphtheria toxin receptor to selectively ablate corticotrophin-releasing factor (CRF) expressing neurons in the central amygdala and show that CRF dependent effects of ethanol on glutamatergic transmission do not depend on the presence of local CRF neurons. Overall, our data suggest that TIP39 signaling may normally limit detrimental effects of environmental stress on emotional state. Dysfunctional responses to stress are widely thought to contribute to depression, implying that this neuropeptide system plays a role in normal resilience.

在发现39个残基（TIP39）及其受体的神经肽结核菌肽肽后，甲状旁腺激素受体2（PTH2R）侧重于研究其生物学作用。神经解剖学映射显示在丘脑和脑干中的离散神经元组中TIP39的合成，将其投影到参与情绪功能的大脑区域。在其解剖学映射之后，实验室项目转向调查源自PTH2R/TIP39系统分布的假设。研究结果包括TIP39调节下丘脑神经内分泌神经元的激活，包括对对冷的适当稳态反应很重要。这些研究导致了针对TIP39动作的一般模型，在高需求条件下，PTH2RS的激活对于鲁棒和足够的兴奋性发射器释放可能是必需的。还发现TIP39既调节急性疼痛敏感性，又调节慢性疼痛模型中正常敏感性。后一种效应似乎涉及层层，这是一种脑干核，其中包含在整个中枢神经系统中具有调节作用的去甲肾上腺素能神经元。结合其他观察结果，这表明TIP39可能是参与感觉刺激与情绪之间关系的调节剂之一。难以区分持续的厌恶感官输入的影响及其长期后果是研究感觉刺激与情绪之间的关系的重要障碍。为了克服这一限制，我们开发了一个范式，以比较逆转小鼠神经性疼痛期间和之后的细胞和行为变化。在袖口去除后的几天内，在坐骨神经周围放置的袖口产生的脊髓背角中的触觉异常性和神经元激活。相比之下，O-Maze，强迫 - s-swim，Y迷宫自发交替和新型对象识别测试表现的变化在神经袖口放置后发展后至少在去除神经袖口后持续了3周。因此，在这种范式中明显解决疼痛后，焦虑和抑郁症状的行为持续存在。关于抑郁症的细胞变化的一种当代观念是，抑制正常成人神经发生起作用。在慢性疼痛模型中抑制了成年海马神经发生，这表明神经发生抑制可能与慢性疼痛相关抑郁症。使用可逆的神经性模型，我们发现在疼痛缓解后至少3周减少了成年海马神经发生。此外，在具有分辨的伤害感受和持续的行为效果的小鼠的基底外侧杏仁核的基底外侧杏仁核中，具有长半衰期的神经元活性标记FOSB保持升高。因此，可逆的神经性范式指出了特定的细胞表型，可用于阐明伤害感受的感觉信号传导和情绪障碍之间的联系。以前，我们发现与野生型相对于野生型，在压力条件下，具有编码TIP39（TIP39-KO）或PTH2R（PTH2R-KO）基因或PTH2R（PTH2R-KO）的小鼠具有增加焦虑样行为。没有TIP39信号传导的小鼠在记忆功能测试中的应力依赖性损害增加。人们普遍认为对压力的功能失调会导致抑郁症，这意味着该神经肽系统在正常的弹性中起着作用。我们使用了创伤后应激障碍（PTSD）模型调查了TIP39/PTH2R对长期恐惧记忆的贡献，在该模型中，小鼠暴露于单个厌恶刺激（脚击）中，此后评估了恐惧记忆，通过测量花费的时间无用的时间（毫无疑问，在动物上，刺激性的刺激）是刺激的环境（刺激性的刺激），而恐惧是刺激的环境，而刺激了恐惧。虽然缺乏TIP39信号传导并没有在冲击后1周引起恐惧记忆的可检测变化，但TIP39-KO和PTH2R-KO小鼠在2和4周后的恐惧背景下，Tip39-KO和PTH2R-KO小鼠的恐惧行为增加了。随着恐惧事件的恐惧记忆，恐惧记忆的增加称为恐惧孵化。基于与PTSD中经常发生的延迟症状发作的相似性，恐惧孵育用于研究可能有助于PTSD的机制。因此，我们研究了缺乏TIP39信号传导的小鼠的恐惧孵育的神经解剖学基础。比较有和没有TIP39信号传导的小鼠之间的神经元激活模式，无论是在脚击之后还是4周后，当动物返回到恐惧的情况下，比较了tip39信号传导，可以阻止杏仁核（MEA）中内侧核中c-fos的正常激活。我们使用了通常包含我们先前开发的PTH2RS的神经元中表达CRE成年酶的PTH2R拮抗剂和小鼠，以研究MEA中的TIP39/PTH2R系统是否负责增强的恐惧孵育。 MEA靶向递送的病毒编码PTH2R拮抗剂再现了KO小鼠的恐惧孵育增强。在立体定位递送的病毒CRE依赖性地编码白喉毒素受体后，通常合成PTH2R的MEA神经元的选择性消融也导致了恐惧孵育。使用病毒传递的CRE-结构酶依赖性设计器受体对MEA PTH2R表达神经元的瞬时抑制作用，仅在脚击之前或刚刚发生后，或者在1个月后进行一次召回测试时，仅由设计仪药物（Dreadd）激活，或者在1个月后进行一次召回测试时，表明在召回时遭到抑制pth2r神经元，但不受召回的限制。将这些观察结果汇总在一起，这些实验首次表明，在创伤事件发生后，杏仁核的内侧核的状态对一个月后的恐惧行为产生了重大影响。它进一步表明，神经肽的信号传导可以对该状态产生重大影响。正在进行的工作研究了TIP39信号传导在杏仁核内侧核中对其他行为的贡献。基于PTH2R-KO小鼠的侵略性下降和增加的社会研究行为，并在药物遗传学抑制内侧杏仁核PTH2R表达神经元后的类似作用，该系统似乎在社会反应的选择中起着重要作用。先前的几项研究提供了证据表明TIP39信号会影响孕产妇行为。在本报告期间，与Arpad dobolyi（ETVS Lornd大学）合作提供了解剖学证据，表明丘脑旁边旁皮区域中继哺乳的TIP39神经元与下丘脑相关信息，以影响孕产妇行为。与理查德·加洛（Richard Gallo）（加利福尼亚大学圣地亚哥分校）的新作品表明，TIP39和PTH2R在皮肤中的细胞种群中都高度表达，并暗示该系统调节角质形成细胞的功能。 Danny Winder (Vanderbilt University) used a virus we made that Cre-dependently expresses the human diphtheria toxin receptor to selectively ablate corticotrophin-releasing factor (CRF) expressing neurons in the central amygdala and show that CRF dependent effects of ethanol on glutamatergic transmission do not depend on the presence of local CRF neurons. 总体而言，我们的数据表明，TIP39信号通常可能会限制环境压力对情绪状态的有害影响。人们普遍认为对压力的功能失调会导致抑郁症，这意味着该神经肽系统在正常的弹性中起着作用。