Vasopressin mediates nonapeptide and glucocorticoid signaling and social dynamics in juvenile dominance hierarchies of a highly social cichlid fish

Abstract: Early-life social experience can strongly affect adult behavior, yet the behavioral mechanisms underlying developmental trajectories are poorly understood. We use the highly social cichlid, Burton’s Mouthbrooder (Astatotilapia burtoni) to investigate juvenile social status and behavior, as well as the underlying neuroendocrine mechanisms. We placed juveniles in pairs or triads and found that they readily establish social status hierarchies, with some group structural variation depending on group size, as well as the relative body size of the group members. Next, we used intracerebroventricular injections to test the hypothesis that arginine vasopressin (AVP) regulates juvenile social behavior and status, similar to adult A. burtoni. While we found no direct behavioral effects of experimentally increasing (via vasotocin) or decreasing (via antagonist Manning Compound) AVP signaling, social interactions directed at the treated individual were significantly altered. This group-level effect of central AVP manipulation was also reflected in a significant shift in whole brain expression of genes involved in nonapeptide signaling (AVP, oxytocin, and oxytocin receptor) and the neuroendocrine stress axis (corticotropin-releasing factor (CRF), glucocorticoid receptors (GR) 1a and 1b). Further, social status was associated with the expression of genes involved in glucocorticoid signaling (GR1a, GR1b, GR2, mineralocorticoid receptor), social interactions with the dominant fish, and nonapeptide signaling activity (AVP, AVP receptor V1aR2, OTR). Together, our results considerably expand our understanding of the context-specific emergence of social dominance hierarchies in juveniles and demonstrate a role for nonapeptide and stress axis signaling in the regulation of social status and social group dynamics.

This Mendeley dataset contains:
Experiment 1: Study of juvenile A. burtoni social behavior and group structure in pairs and triads, including matched pairs (size-matched fish), mismatched pairs (larger and smaller fish), matched triads (larger juvenile with smaller size-matched fish), and mismatched triads (larger, medium, and small fish). The Experiment 1 variable key describes each variable.

Experiment 2: Pharmacological manipulation of juvenile A. burtoni in matched triads (larger juvenile with smaller size-matched fish) using intracerebroventricular (ICV) injection. One of the size-matched fish received ICV injection of vehicle (control). The other received either arginine vasotocin or antagonist Manning Compound. The Experiment 2 variable key describes each variable.

摘要：早期社会经历对成年行为具有显著影响，然而，发育轨迹背后的行为机制尚不明确。本研究采用高度社会化的斑马鱼，布顿口孵鱼（Astatotilapia burtoni）作为研究对象，旨在探究幼鱼的社交地位和行为，以及其背后的神经内分泌机制。我们将幼鱼配对或组成三联体，发现它们能够迅速建立社交地位等级，且随着群体规模的改变以及群体成员相对体型的不同，群体结构亦存在一定程度的变异。随后，我们通过脑室内注射的方法检验了精氨酸加压素（AVP）调节幼鱼社交行为和地位假设，这与成年布顿口孵鱼的行为相似。尽管我们未发现通过血管加压素（实验性增加）或拮抗剂曼宁化合物（实验性减少）改变AVP信号的直接行为效应，但针对接受治疗的个体的社交互动却发生了显著改变。这种中枢AVP操纵在群体层面的效应也体现在涉及非肽信号（AVP、催产素及其受体）和神经内分泌应激轴（促肾上腺皮质激素释放因子（CRF）、糖皮质激素受体（GR）1a和1b）的全脑基因表达上的显著转变。此外，社交地位与涉及糖皮质激素信号（GR1a、GR1b、GR2、矿皮质激素受体）的基因表达、与优势鱼的社交互动以及非肽信号活性（AVP、AVP受体V1aR2、OTR）相关。综合来看，我们的研究结果大大扩展了我们对幼鱼社交地位等级在特定情境下产生的理解，并证明了非肽和应激轴信号在调节社交地位和社会群体动态中的作用。该Mendeley数据集包含以下内容：实验1：研究布顿口孵鱼幼鱼在配对和三联体中的社交行为和群体结构，包括匹配配对（体型匹配的鱼）、不匹配配对（体型较大和较小的鱼）、匹配三联体（体型较大的幼鱼与体型较小且匹配的鱼）和不匹配三联体（体型较大、中等和较小的鱼）。实验1变量键描述了每个变量。实验2：在匹配三联体（体型较大的幼鱼与体型较小且匹配的鱼）中使用脑室内注射（ICV）对布顿口孵鱼幼鱼进行药理操纵。其中一只体型匹配的鱼接受了脑室内注射的溶剂（对照组）。另一只接受了精氨酸加压素或拮抗剂曼宁化合物的注射。实验2变量键描述了每个变量。