PACAP Modulation of Ca2+ Activity in Neonatal Mouse OB

PACAP 对新生小鼠 OB 中 Ca2 活性的调节

• 批准号: 8591175
• 负责人: Mavis Amity Irwin
• 金额: $ 3.03万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-12-01 至 2014-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8591175
• 关键词: Acute; Adult; Affect; Auditory; Autistic Disorder; Behavior; Birth; Body Temperature; Brain region; Cells; Cerebellum; Chemical Stimulation; Cytoplasmic Granules; Data; Development; Disease; Foundations; Future; G-Protein-Coupled Receptors; Gene Mutation; Hippocampus (Brain); Image; Immigration; Injury; Interneurons; Knock-out; Learning; Life; Maps; Mediating; Migration Assay; Monitor; Mus; Neonatal; Neurodegenerative Disorders; Neurons; Neuropeptides; Neurotransmitters; Newborn Infant; Nipples; Odors; Olfactory Epithelium; PACAPR-1 protein; Pathway interactions; Peptides; Physiological; Play; Proteins; Role; Schizophrenia; Sensory; Slice; System; Temperature; Testing; Therapeutic; Therapeutic Uses; Time; Transgenic Mice; Visual; Weaning; adult neurogenesis; base; cell type; central nervous system injury; density; dentate gyrus; design; feeding; gamma-Aminobutyric Acid; granule cell; insight; knockout animal; migration; natural hypothermia; neonatal death; nervous system disorder; neuroblast; neuron development; neuronal circuitry; neuronal survival; neurotransmitter release; new therapeutic target; novel; olfactory bulb; pituitary adenylate cyclase activating polypeptide; postnatal; prevent; pup; receptor; receptor expression; response; sensory system

Project Summary Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) is a pleiotropic peptide with functions in development and throughout life [4]. PACAP knockout (KO) animals will die shortly after birth due to an inability to maintain core body temperature [5]. Our observation that preventing hypothermia in PACAP KO pups does not eliminate poor survival suggests that other functions such as olfactory mediated feeding may be disturbed. Both PACAP and its G-protein coupled receptor (PAC1) are highly expressed in the olfactory bulb (OB) throughout life suggesting PACAP plays an important role in the development, survival and replacement of neurons within the bulb. Surprisingly, there have been no studies on the role of PACAP in modulating the Ca[2+] activity, migration, and maturation of developing OB neurons. In other CNS regions, Ca[2+] activity in the form of spontaneous oscillations is critical for the establishment and survival of developing neuronal circuitry, especially prior to sensory input [6]. GABA is excitatory in immature neurons and has been implicated in this early developmental activity but the control of maturation in olfactory interneurons is poorly understood. However, our preliminary data show that PACAP induces transient and sustained Ca[2+] oscillations in multiple cell types of the neonatal OB. Our focus in the first aim will be on the developing GABAergic granule cells (GCs) because they are thought to express PAC1Rs and can be identified using GAD2- and Dlx2- tdTomato transgenic mice. The developing GCs will be evaluated for PACAP responses and their maturity tested with GABA, which will be an excitatory neurotransmitter for the immature cells which maintain high intracellular Cl- levels and depolarize with GABA stimulation. The second aim will be determining the role of PACAP in the migration and maturation of immature OB interneurons. It will be directly accomplished using migration assays on cultured GAD2 or Dlx2 tdTomato mice OB cells. Morphological changes associated with maturation will also be examined. This proposal will examine the role of PACAP during early postnatal development of OB circuitry and is based on studies of PACAP and PAC1 receptor expression in the OB and other brain regions. However, my studies are the first dynamic imaging studies of PACAP in identified cells of neonatal OB. Because little is known about the function of PACAP in the OB, the emphasis of my proposal will be to lay the foundation for future understanding of how PACAP affects the development of OB circuitry. A number of neurological diseases such as autism, bipolar disease, and schizophrenia are thought to originate from problems in early development of neuronal circuits. Understanding the role of PACAP in early circuitry development may provide a novel therapeutic target for these devastating diseases. Furthermore, understanding how PACAP affects developing interneurons may aid in designing strategies for adult neurogenesis following injury or disease.

项目概要 垂体腺苷酸环化酶激活多肽 (PACAP) 是一种多效性肽，在发育和整个生命周期中具有功能 [4]。 PACAP 基因敲除 (KO) 动物将在出生后不久因无法维持核心体温而死亡 [5]。我们观察到，预防 PACAP KO 幼崽体温过低并不能消除不良的生存率，这表明嗅觉介导的进食等其他功能可能会受到干扰。 PACAP 及其 G 蛋白偶联受体 (PAC1) 在整个生命过程中在嗅球 (OB) 中高度表达，表明 PACAP 在嗅球内神经元的发育、存活和替换中发挥着重要作用。令人惊讶的是，目前还没有关于 PACAP 在调节 OB 神经元发育中的 Ca[2+] 活性、迁移和成熟中的作用的研究。在其他 CNS 区域，自发振荡形式的 Ca[2+] 活动对于发育中的神经元回路的建立和生存至关重要，尤其是在感觉输入之前 [6]。 GABA 对未成熟神经元具有兴奋性，并且与这种早期发育活动有关，但对嗅觉中间神经元成熟的控制知之甚少。然而，我们的初步数据表明，PACAP 在新生儿 OB 的多种细胞类型中诱导瞬时和持续的 Ca[2+] 振荡。 我们第一个目标的重点是开发 GABA 能颗粒细胞 (GC)，因为它们被认为表达 PAC1R，并且可以使用 GAD2- 和 Dlx2- tdTomato 转基因小鼠进行识别。将评估发育中的 GC 的 PACAP 反应，并用 GABA 测试其成熟度，GABA 将是未成熟细胞的兴奋性神经递质，可维持高细胞内 Cl- 水平并通过 GABA 刺激去极化。 第二个目标是确定 PACAP 在未成熟 OB 中间神经元的迁移和成熟中的作用。这将通过对培养的 GAD2 或 Dlx2 tdTomato 小鼠 OB 细胞进行迁移测定来直接完成。还将检查与成熟相关的形态变化。 该提案将基于对 OB 和其他大脑区域中 PACAP 和 PAC1 受体表达的研究，研究 PACAP 在产后早期发育过程中的作用。然而，我的研究是 PACAP 在已识别的新生儿 OB 细胞中的首次动态成像研究。由于人们对 PACAP 在 OB 中的功能知之甚少，因此我建议的重点是为将来了解 PACAP 如何影响 OB 电路的开发奠定基础。许多神经系统疾病，如自闭症、双向情感障碍和精神分裂症，被认为源于神经元回路早期发育的问题。了解 PACAP 在早期电路发育中的作用可能为这些破坏性疾病提供新的治疗靶点。此外，了解 PACAP 如何影响发育中的中间神经元可能有助于设计损伤或疾病后成人神经发生的策略。