Neural Mechanisms of Dominance Behavior

支配等级组织了所有社会性动物的社会行为，并且有助于它们的行为是立即可识别的。 尽管社会支配地位的普遍性和重要性，很少有人了解它在任何物种的神经基板。 5-羟色胺已被确定为一种神经递质，有助于介导脊椎动物和无脊椎动物的社会优势。 虽然5-羟色胺在中枢神经系统中有许多作用和作用部位，但与社会优势相关的作用和部位在很大程度上是未知的。 解决这个问题的方法之一是研究血清素如何影响有助于控制行为特定方面的神经回路，并确定这些影响如何随社会支配地位而变化。 在小龙虾的逃生行为的神经回路的充分理解提供了一个机会，以确定如何在动物的社会地位的变化导致的变化，血清素对神经回路的兴奋性逃跑的影响。 早期的研究表明，5-羟色胺对外侧巨（LG）指令神经元逃避的兴奋性的影响各不相同，从社会主导的小龙虾的促进到从属小龙虾的抑制。 在小龙虾中已经鉴定出两种5-羟色胺分子受体，并且已经描述了它们在小龙虾神经系统中的分布。 该项目将测试这样一个假设，即血清素在占主导地位和从属地位的小龙虾中的作用的差异是由于影响LG神经元兴奋性的血清素受体的分布或功效的差异。LG逃逸回路中受体分布的差异将使用受体的荧光标记抗体来确定。 将使用对每种受体特异性的5-羟色胺激动剂和拮抗剂来确定其活化如何有助于5-HT在每种社会类型动物中的作用。 这项研究将展示5-羟色胺受体的分布和作用的差异如何在显性和隐性小龙虾中产生神经系统功能的差异。 由于血清素的作用影响许多动物的社会地位，这些机制可能在动物王国中广泛存在。 这项工作将提供研究培训的机会，博士后学生和一些本科生从GSU和行为神经科学中心（CBN）的其他成员。 这项研究将在CBN的侵略和联盟合作实验室进行介绍和讨论，从而为CBN的使命做出贡献。

Dominance hierarchies organize the social behavior of all social animals, and the behaviors that contribute to them are immediately recognizable. Despite the ubiquity and importance of social dominance, little is understood about its neural substrates in any species. Serotonin has been identified as a neurotransmitter that helps mediate social dominance in vertebrates and invertebrates. Although serotonin has many effects and sites of action in the central nervous system, the effects and sites that are relevant to social dominance are largely unknown. One approach to this problem is to examine how serotonin affects neural circuits that help govern specific aspects of behavior, and to determine how these effects change with social dominance status. The well-understood neural circuitry for escape behavior in crayfish provides an opportunity to determine how changes in an animal's social status lead to changes in the effect of serotonin on the excitability of neural circuits for escape. Earlier work has shown that serotonin's effect on the excitability of the lateral giant (LG) command neuron for escape varies from facilitation in socially dominant crayfish to inhibition in subordinate crayfish. Two molecular receptors for serotonin have been identified in crayfish, and their distributions in the crayfish nervous system have been described. This project will test the hypothesis that the differences in serotonin's effects in dominant and subordinate crayfish result from differences in the distribution or the efficacy of serotonin receptors that affect the LG neuron's excitability. Differences in receptor distribution in the LG escape circuit will be determined using fluorescently labeled antibodies to the receptors. Serotonin agonists and antagonists specific to each receptor will be used to determine how its activation contributes to the effect of 5-HT in each social type of animal. This research will show how differences in the distribution and action of serotonin receptors produce differences in nervous system function in dominant and subordinate crayfish. Because the action of serotonin affects social status in many animals, these mechanisms are likely to be widespread in the animal kingdom. This work will provide research training opportunities for a Post-doctoral student and a few undergraduates drawn from GSU and from other members of the Center for Behavioral Neuroscience (CBN). The research will be presented and discussed at the CBN's Aggression and Affiliation Collaboratories, and so contribute to the CBN mission.