Department of Biology, University of South Dakota, 414 East Clark St, Vermillion, SD 57069, USA.
Physiol Behav. 2010 Apr 19;99(5):571-8. doi: 10.1016/j.physbeh.2010.01.025. Epub 2010 Feb 4.
Individual social status discriminates rapid neuroendocrine responses to non-social stress in male Anolis carolinensis, but whether such status-influenced reactions are retained in response to subsequent social stress is unknown. Dominant and subordinate males modify their behavioral responses to social challenge according to familiarity of the opponent, suggesting that accompanying neuroendocrine responses may differ according to opponent recognition despite social rank. We examined endocrine and neurochemical correlates of prior social status and opponent recognition during the opening stages of social challenge. Male pairs interacted and established dominant/subordinate status, followed by 3 days separation. Subsequently, subjects were paired with either the same opponent or an unfamiliar male according to rank (dominant with subordinate). After 90 s of social exposure, subjects were caught and brains and plasma collected for measurement of circulating corticosterone and limbic monoamines. Controls included pairs experiencing just one 90 s encounter plus a group of non-interacting subjects. Opponent recognition differentiated status-influenced responses, such that dominant lizards paired with familiar subordinate opponents had increased hippocampal dopamine and epinephrine, but showed increased plasma corticosterone and ventral tegmental area (VTA) norepinephrine when challenged with an unfamiliar opponent. Subordinate lizards encountering familiar opponents also had increased corticosterone, along with decreased hippocampal dopamine and increased VTA epinephrine, but showed no changes in response to an unfamiliar opponent. Such plasticity in status-influenced rapid neuroendocrine responses according to opponent recognition may be necessary for facilitating production of behavioral responses adaptive for particular social contexts, such as encountering a novel versus familiar opponent.
个体社会地位会影响雄性卡罗莱纳变色龙对非社会性压力的快速神经内分泌反应，但这种受地位影响的反应是否会保留在对随后的社会性压力的反应中尚不清楚。优势和劣势雄性会根据对手的熟悉程度改变其对社会挑战的行为反应，这表明尽管存在社会等级，但伴随的神经内分泌反应可能会因对手识别而有所不同。我们检查了先前的社会地位和对手识别的内分泌和神经化学相关性，这些在社会挑战的开场阶段会出现。雄性成对互动并建立优势/劣势地位，然后分开 3 天。随后，根据等级（优势与劣势）将对象与相同的对手或不熟悉的雄性配对。在 90 秒的社交接触后，抓住对象并收集大脑和血浆，以测量循环皮质酮和边缘单胺。对照组包括仅经历一次 90 秒接触的配对和一组不相互作用的对象。对手识别区分了受地位影响的反应，例如，与熟悉的劣势对手配对的优势蜥蜴的海马多巴胺和肾上腺素增加，但与不熟悉的对手接触时，血浆皮质酮和腹侧被盖区（VTA）去甲肾上腺素增加。遇到熟悉对手的劣势蜥蜴也会增加皮质酮，同时减少海马多巴胺并增加 VTA 肾上腺素，但对不熟悉的对手没有反应。根据对手识别，地位影响的快速神经内分泌反应的这种可塑性可能对于促进产生适应特定社会环境的行为反应是必要的，例如遇到新的或熟悉的对手。
