EFFECT OF ANDROGENS ON BEHAVIOR THROUGH NPY MODULATION

雄激素通过 NPY 调节对行为的影响

• 批准号: 8360152
• 负责人: Jennifer Luz Barreto Estrada
• 金额: $ 10.35万
• 依托单位: UNIVERSITY OF PUERTO RICO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8360152
• 关键词: Accessory Sex Organs; Actins; Adolescent; Affect; Age; Agonist; Amygdaloid structure; Anabolic steroids; Androgens; Animals; Anxiety; Anxiety Disorders; Behavior; Behavior Control; Behavioral; Bilateral; Binding; Biochemical; Biomedical Research; Brain; Brain region; Cannulas; Cell Nucleus; Cognitive; Complex; Data; Dendritic Spines; Dose; Ejaculation; Emotional; Event; Exposure to; Female; Functional disorder; Funding; Goals; Gonadal Steroid Hormones; Grant; Growth; Hormonal; Hormones; Hypothalamic structure; Immunohistochemistry; Implant; Infusion procedures; Injection of therapeutic agent; Knowledge; Label; Learning; Mediating; Memory; Molecular; Motivation; National Center for Research Resources; Neurons; Neuropeptides; Neurosecretory Systems; Neurotransmitters; Pharmaceutical Preparations; Play; Principal Investigator; Process; Proteins; Puberty; Puerto Rico; Rattus; Regulation; Reporting; Reproductive Behavior; Research; Research Infrastructure; Resources; Role; Sex Behavior; Source; Symptoms; Synapses; Synaptic Potentials; Synaptic plasticity; Testing; United States National Institutes of Health; cost; critical developmental period; drebrins; in vivo; insight; male; neuropeptide Y; preference; programs; reproductive; reproductive function; response; synaptic function

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Puberty has been described as a critical developmental period susceptible to changes at the hormonal level, which can modulate cellular and molecular substrates leading to particular behaviors. Secretion of male hormones is important to promote growth of the accessory sex organs and to establish adequate reproductive function. Beside actions of sex steroids in the brain regulating reproductive behavior, androgens modulate non-reproductive behaviors such as anxiety, and emotional learning. Interestingly, neuropeptides are cellular substrates that have been shown to be under hormonal control, have been associated with different domains of behaviors and are highly expressed in brain regions mediating these behaviors. Knowledge that androgens can modulate specific cellular substrates such as neuropeptides has raised relevant questions regarding the cellular mechanisms responsible for the observed behavioral changes under supraphysiological concentrations. We have previously found that anabolic androgenic steroids (AAS) decrease neuropeptide Y (NPY) levels in the amygdala (AMY) of female pubertal rats and an increase in NPY in the ventromedial nuclei (VMN) of pubertal males. This proposal aims to determine the role of NPY in androgen modulation of reproductive behaviors and emotional learning during early exposure to AAS. Pubertal rats (PN32) will be chronically exposed to high doses of AAS followed by assessment of anxiety-like behaviors using the elevated plus maze (EPM), and emotional learning, using the passive avoidance task (PAT) in females and sexual behavior in males. Anxiety and emotional learning will be study in females since these behaviors are controlled by the AMY, and sexual motivation will be studied in males given that the VMN plays an important role in this component of sexual behavior. To further investigate if AAS affect emotional learning and reproductive behaviors through NPY mechanisms, peripubertal animals (PN28) will be systemically exposed for one week to androgens and will be implanted with bilateral injection cannulae in the AMY (females) and the VMN (males). After two weeks of AAS exposure, and still in puberty (PN35), pharmacological drugs (NPY ago/antagonists) will be intracranially infused. Five minutes after the infusion EPM, PAT and sexual motivation will be performed. This study will contribute with new cellular insights of androgen effects in puberty, which is the most sensitive age to engage in androgen misuse and most deleterious neuroendocrine and psychiatric symptoms are observed. SPECIFIC AIMS Data have demonstrated an important role for androgens in sexual behaviors, anxiety and learning & memory. Interestingly, all of these behaviors are modulated throughout biochemical molecules such as neurotransmitters and neuropeptides. The long-term goal of this research program will be focused on providing a better understanding of the role of neuropeptides in reproductive behaviors and emotional learning after in vivo exposure to androgens. Given that anabolic androgenic steroid (AAS) misuse is associated with multiple reproductive-related behaviors and learning and memory, this study will provide critical data of the biochemical aspects of behavioral changes associated with androgen exposure, especially in adolescents, where an increased misuse has been reported. This study propose: Aim 1. Determine the role of Neuropeptide Y (NPY) in pubertal brain regions involved in anxiety and emotional learning after androgen exposure. The amygdala (AMY) is a complex brain region associated with emotional processing and anxiety disorders (Ledoux, 1998) that has been demonstrated to be under hormonal influence (Cooke et al., 2003; 2006). Androgen regulation of peptidergic cellular substrates controlling behavior has been well documented (Clark and Henderson, 2003). In the context of this hormonal control, we have found from results of our first funding cycle that AAS decrease NPY levels in the AMY of female pubertal rats (Barreto-Estrada et al., unpublished results). Since NPY has been related to anxiety and emotional events (Carvajal, et al., 2006; Primeaux et al., 2005), our hypothesis is that in vivo exposure to AAS will elicit changes in anxiety and/or emotional learning through NPY mechanisms in pubertal females. To test this hypothesis, pubertal female rats (PN32) will be chronically exposed to high doses of AAS. Thereafter, assessment of anxiety-like behaviors using the elevated plus maze (EPM), and emotional learning, using the passive avoidance task (PAT) will be performed. To find out if AAS affect anxiety and/or emotional learning through NPY mechanisms, peripubertal females (PN28) will be systemically exposed to androgens and also will be implanted with bilateral injection cannulae in the AMY. After two weeks of AAS exposure, and still in puberty (PN35), NPY agonist will be intracranially infused in the AMY. Five minutes after the infusion EPM and PAT will be performed. AAS-affected behaviors will be reversed with the antagonist. Aim 2. Determine the role of NPY in pubertal brain regions involved in reproductive-related behaviors after androgen exposure. The VMN is a hypothalamic nuclei principally involved in reproductive-related behaviors. In particular, it is associated with the female sexual response, while in males it is associated with sexual motivation. Similar to the AMY, the VMN has been shown to be under hormonal influence (Harding and McGinnis, 2004). We have found from previous results that AAS increases NPY levels in the VMN of male pubertal rats (Barreto-Estrada et al., unpublished results). Since the VMN has been related to the motivational component of sexual behavior in males, and given that the VMN express NPY (Beck, 2006), our hypothesis is that in vivo exposure to AAS will elicit changes in sexual motivation through NPY mechanisms in pubertal males. To test this hypothesis, pubertal male rats (PN32) will be chronically exposed to high doses of AAS. Sexual motivation parameters such as the latency to the first mount, latency to the first ejaculation and the partner preference will be assessed. To find out if AAS affect sexual motivation through NPY mechanisms, peripubertal males (PN28) will be systemically exposed to androgens and will also be implanted with bilateral injection cannulae in the VMN. After two weeks of AAS exposure, and still in puberty (PN35), NPY antagonist will be intracranially infused in the VMN. Sexual motivation will be assessed five minutes after the antagonist infusion. AASaffected behaviors will be reversed with the antagonist. Aim 3. Establish the effect of AAS in synaptic plasticity Synaptic connectivity and neuronal branching have been shown to be affected by androgens (Cherry et al., 1992; McEwen, 1992). This aim will study the effect of AAS in synaptic function, in particular dendritic spines that could be regulated by hormones (Smart and Halpain, 2000), and that are known to be affected in cognitive processes (Julien et al., 2008). Double labeling immunohistochemistry for drebrin, an actin-binding dendritic spine protein (Sekino et al., 2007) and NPY will be performed in the AMY and VMN. Modulation of the synaptic microenvironment by AAS might be responsible for changes in behavior. The present aim investigates the potential synaptic dysfunction after AAS exposure in emotional memory, anxiety and sexual behaviors.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的主要研究者可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 青春期被描述为容易受到激素水平变化的关键发育时期，激素水平可以调节导致特定行为的细胞和分子底物。雄性激素的分泌对于促进副性器官的生长和建立足够的生殖功能很重要。除了大脑中性类固醇调节生殖行为的作用外，雄激素还调节非生殖行为，例如焦虑和情绪学习。有趣的是，神经肽是细胞底物，已被证明受到激素控制，与不同的行为领域相关，并且在介导这些行为的大脑区域中高度表达。人们认识到雄激素可以调节特定的细胞底物，例如神经肽 有关在超生理浓度下观察到的行为变化的细胞机制的相关问题。我们之前发现，同化雄激素类固醇 (AAS) 会降低雌性青春期大鼠杏仁核 (AMY) 中的神经肽 Y (NPY) 水平，并增加青春期雄性大鼠腹内侧核 (VMN) 中的 NPY 水平。该提案旨在确定 NPY 在早期暴露于 AAS 期间雄激素调节生殖行为和情绪学习中的作用。青春期大鼠（PN32）将长期暴露于高剂量的 AAS，然后使用高架十字迷宫（EPM）评估焦虑样行为，并使用雌性被动回避任务（PAT）和雄性性行为进行情绪学习。将研究女性的焦虑和情绪学习，因为这些行为是由 AMY 控制的，并且将研究男性的性动机，因为 VMN 在性行为的这一组成部分中发挥着重要作用。为了进一步研究 AAS 是否通过 NPY 机制影响情绪学习和生殖行为，青春期动物（PN28）将全身暴露于雄激素一周，并在体内植入双侧注射插管。 AMY（女性）和 VMN（男性）。 AAS 暴露两周后，仍处于青春期 (PN35)，将颅内注射药物（NPY 前/拮抗剂）。输注五分钟后将进行 EPM、PAT 和性动机。这项研究将有助于提供新的细胞见解 青春期雄激素的影响是雄激素滥用最敏感的年龄，并且观察到最有害的神经内分泌和精神症状。 具体目标 数据表明雄激素在性行为、焦虑以及学习和记忆中发挥着重要作用。有趣的是，所有这些行为都受到神经递质和神经肽等生化分子的调节。该研究计划的长期目标将集中于更好地了解神经肽在生殖行为和情绪中的作用 体内暴露于雄激素后的学习。鉴于合成代谢雄激素类固醇 (AAS) 的滥用与多种生殖相关行为以及学习和记忆有关，这项研究将提供与雄激素暴露相关的行为变化的生化方面的关键数据，特别是在青少年中，据报道，青少年的滥用情况有所增加。本研究提出： 目标 1. 确定神经肽 Y (NPY) 在雄激素暴露后涉及焦虑和情绪学习的青春期大脑区域中的作用。 杏仁核（AMY）是一个与情绪处理和焦虑症相关的复杂大脑区域（Ledoux，1998），已被证明受到荷尔蒙的影响（Cooke 等，2003；2006）。雄激素对控制行为的肽能细胞底物的调节已得到充分记录 （克拉克和亨德森，2003）。在这种激素控制的背景下，我们从第一个资助周期的结果中发现，AAS 降低了雌性青春期大鼠 AMY 中的 NPY 水平（Barreto-Estrada 等人，未发表的结果）。由于 NPY 与焦虑和情绪事件有关（Carvajal 等，2006； Primeaux 等人，2005），我们的假设是体内暴露于 AAS 会通过青春期女性的 NPY 机制引起焦虑和/或情绪学习的变化。为了验证这一假设，青春期雌性大鼠 (PN32) 将长期暴露于高剂量的 AAS。此后，使用高架十字迷宫（EPM）评估焦虑样行为，并使用被动式情绪学习 将执行回避任务（PAT）。为了查明 AAS 是否通过 NPY 机制影响焦虑和/或情绪学习，青春期女性 (PN28) 将全身暴露于雄激素，并在 AMY 中植入双侧注射插管。暴露于 AAS 两周后，仍处于青春期 (PN35)，NPY激动剂将被颅内注入AMY中。输注五分钟后将进行 EPM 和 PAT。受 AAS 影响的行为将随着拮抗剂而逆转。 目标 2. 确定 NPY 在雄激素暴露后参与生殖相关行为的青春期大脑区域中的作用。 VMN 是一个下丘脑核团，主要参与生殖相关行为。特别是，它与女性的性反应有关，而在男性中，它与性动机有关。与 AMY 类似，VMN 已被证明受到荷尔蒙的影响（Harding 和 McGinnis，2004）。我们从之前的结果中发现，AAS 会增加雄性青春期大鼠 VMN 中的 NPY 水平（Barreto-Estrada 等人，未发表的结果）。由于 VMN 与男性性行为的动机成分相关，并且考虑到 VMN 表达 NPY（Beck，2006），我们的假设是，体内暴露于 AAS 将通过青春期男性的 NPY 机制引起性动机的变化。为了检验这一假设，青春期雄性大鼠 (PN32) 将长期暴露于高剂量的 AAS。性动机参数，例如第一次射精的潜伏期、第一次射精的潜伏期和伴侣偏好将 进行评估。为了查明 AAS 是否通过 NPY 机制影响性动机，青春期男性 (PN28) 将全身暴露于雄激素，并且还将在 VMN 中植入双侧注射插管。 AAS 暴露两周后，仍处于青春期 (PN35)，将在颅内注射 NPY 拮抗剂 注入VMN。拮抗剂输注后五分钟将评估性动机。受 AA 影响的行为将与拮抗者逆转。 目标 3. 确定 AAS 在突触可塑性中的作用 突触连接和神经元分支已被证明受到雄激素的影响（Cherry 等人，1992；McEwen，1992）。这一目标将研究 AAS 对突触功能的影响，特别是可以受激素调节的树突棘（Smart 和 Halpain，2000），并且已知会影响认知过程（Julien 等，2008）。 drebrin、一种肌动蛋白结合树突棘蛋白（Sekino 等，2007）和 NPY 的双标记免疫组织化学将在 AMY 和 VMN 中进行。 AAS 对突触微环境的调节可能是导致行为变化的原因。目前的目的是研究 AAS 暴露后情绪记忆、焦虑和性行为中潜在的突触功能障碍。