Characterization of the adaptive balance between defensive and appetitive behaviors induced by aversive experience

暴露于厌恶性刺激会触发防御和食欲行为之间的适应性平衡， 为了生存，需要快速获取，随时间存储，并且必须灵活地适应修改 在生物体的内部和/或外部状态。详细描述了 平衡的形成、储存和灵活性对于理解这一基本过程如何运作至关重要 帮助生物在不断变化的环境中生存。在模式生物失智症中， 刺激诱导一种平衡，表现为防御反射的同时增强（一种初级形式 学习被称为敏化）和抑制进食的食欲行为。该余额存储在 在短期（分钟到小时）和长期（天）的时间范围内，取决于厌恶的量 exposure.这种平衡至少部分是通过相应神经元内关键部位的变化来维持的。 回路：进食决策神经元B51的兴奋性降低，与兴奋性增加共表达 控制防御性反射的感觉神经元。私家侦探的实验室已经开始分析 平衡的生化机制。短期致敏和摄食抑制是由 不同的调节剂，血清素（5-HT）和一氧化氮（NO）。相反，长期敏感化 和摄食抑制共同需要NO。虽然敏化和摄食抑制， 同时引起以下厌恶的经验，长期储存的敏化后，多个 已经发现，重复暴露于令人厌恶的刺激物的天数比抑制进食的时间更长，这表明 可能限制平衡随时间维持的约束的存在。 使用体内和体外程序的组合，这个R15区域赠款将：1）确定是否 共同的可塑性规则支配着摄食和防御回路的变化; 2）进一步表征了 调节系统的基本存储的平衡和3）检查的灵活性和限制， 平衡的储存。 结果将有助于从根本上理解如何在防御和 食欲行为在正常的神经系统中产生和储存。所获得的知识可以 最终提供了重要的见解，这些神经系统疾病所造成的缺陷，在正确的 这种平衡的形成，储存和灵活性，从而与国家研究所的使命保持一致。 神经系统疾病和中风。拟议的实验将主要由本科生进行 学生，在PI，研究助理和/或高级研究生的监督下。这个项目 代表了德克萨斯A&M大学的一个独特的机会-科珀斯克里斯蒂，一个西班牙裔服务机构， 提高其在生物医学研究中的知名度，并使其本科生能够在该领域进行研究 神经科学领域的专家，在这个机构里并不多见

Exposure to aversive stimuli triggers an adaptive balance between defensive and appetitive behaviors, which, for survival, needs to be acquired rapidly, stored over time, and must be flexible to accommodate modifications in the organism’s internal and/or external state. A detailed characterization of the mechanisms underlying the formation, storage and flexibility of the balance is critical to understand how this fundamental process operates to help organisms survive in a changing environment. In the model organism Aplysia, exposure to aversive stimuli induces a balance that manifests as concurrent enhancement of defensive reflexes (an elementary form of learning known as sensitization) and suppression of the appetitive behavior of feeding. This balance is stored in short-term (minutes to hours) and long-term (days) timeframes depending on the amount of aversive exposure. The balance is sustained, at least in part, by changes at key sites within the corresponding neural circuits: decreased excitability of feeding decision-making neuron B51 co-expressed with increased excitability of the sensory neurons controlling defensive reflexes. The PI’s lab has begun to analyze the cellular and biochemical mechanism of the balance. Short-term sensitization and feeding suppression are mediated by distinct modulators, serotonin (5-HT) and nitric oxide (NO), respectively. Conversely, long-term sensitization and feeding suppression share the requirement of NO. Although sensitization and feeding suppression are concurrently induced following aversive experience, the long-term storage of sensitization following multiple days of repeated exposures to aversive stimuli has been found to outlast the suppression of feeding, suggesting the presence of constraints that may limit the maintenance of the balance over time. Using a combination of in vivo and in vitro procedures, this R15 AREA grant will: 1) determine whether common plasticity rules govern changes in feeding and defensive circuits; 2) further characterize the modulatory systems underlying the storage of the balance and 3) examine flexibility and constraints in the storage of the balance. The outcomes will contribute to the fundamental understanding of how the balance between defensive and appetitive behaviors in generated and stored in the normal nervous system. The acquired knowledge may ultimately provide important insights into those neurological disorders caused by deficits in the correct formation, storage and flexibility of this balance, thus aligning with the mission of the National Institute of Neurological Disorders & Stroke. The proposed experiments will be performed primarily by undergraduate students, under the supervision of the PI, research associate and/or a senior graduate student(s). This project represents a unique opportunity for Texas A&M University – Corpus Christi, a Hispanic-Serving Institution, to increase its visibility in biomedical research, and for its undergraduate students to conduct research in the field of neuroscience, which is underrepresented at this institution.