Choleris E, Ogawa S, Kavaliers M, Gustafsson J-A, Korach K S, Muglia L J, Pfaff D W
Department of Psychology, University of Guelph, Guelph, Ontario, Canada.
Genes Brain Behav. 2006 Oct;5(7):528-39. doi: 10.1111/j.1601-183X.2006.00203.x.
Social recognition, processing, and retaining information about conspecific individuals is crucial for the development of normal social relationships. The neuropeptide oxytocin (OT) is necessary for social recognition in male and female mice, with its effects being modulated by estrogens in females. In previous studies, mice whose genes for the estrogen receptor-alpha (alpha-ERKO) and estrogen receptor-beta (beta-ERKO) as well as OTKO were knocked out failed to habituate to a repeatedly presented conspecific and to dishabituate when the familiar mouse is replaced by a novel animal (Choleris et al. 2003, Proc Natl Acad Sci USA 100, 6192-6197). However, a binary social discrimination assay, where animals are given a simultaneous choice between a familiar and a previously unknown individual, offers a more direct test of social recognition. Here, we used alpha-ERKO, beta-ERKO, and OTKO female mice in the binary social discrimination paradigm. Differently from their wild-type controls, when given a choice, the KO mice showed either reduced (beta-ERKO) or completely impaired (OTKO and alpha-ERKO) social discrimination. Detailed behavioral analyses indicate that all of the KO mice have reduced anxiety-related stretched approaches to the social stimulus with no overall impairment in horizontal and vertical activity, non-social investigation, and various other behaviors such as, self-grooming, digging, and inactivity. Therefore, the OT, ER-alpha, and ER-beta genes are necessary, to different degrees, for social discrimination and, thus, for the modulation of social behavior (e.g. aggression, affiliation).
对同种个体进行社会识别、处理和保留信息对于正常社会关系的发展至关重要。神经肽催产素（OT）对雄性和雌性小鼠的社会识别是必需的，其作用在雌性中受雌激素调节。在先前的研究中，雌激素受体α（α-ERKO）、雌激素受体β（β-ERKO）以及OTKO基因被敲除的小鼠无法适应反复出现的同种个体，并且当熟悉的小鼠被新动物取代时也不会产生去习惯化反应（Choleris等人，2003年，《美国国家科学院院刊》100, 6192 - 6197）。然而，一种二元社会辨别试验，即动物在熟悉个体和先前未知个体之间同时进行选择，为社会识别提供了更直接的测试。在此，我们在二元社会辨别范式中使用了α-ERKO、β-ERKO和OTKO雌性小鼠。与野生型对照不同，在进行选择时，基因敲除小鼠表现出社会辨别能力降低（β-ERKO）或完全受损（OTKO和α-ERKO）。详细的行为分析表明，所有基因敲除小鼠对社会刺激的焦虑相关伸展接近行为减少，在水平和垂直活动、非社会探究以及诸如自我梳理、挖掘和静止不动等各种其他行为方面没有整体受损。因此，OT、ER-α和ER-β基因在不同程度上对于社会辨别以及进而对社会行为（如攻击、亲和）的调节是必需的。
