Social signals play a primary role in regulating social relationships among male mice. The present series of experiments investigated the neural mechanisms underlying an induction of amicable cues that facilitate social approach in male mice of the C57BL/6 (B6) and BALB/c (BALB) strains. Male mice exhibit approach behavior and suppression of territorial scent marking toward amicable counterparts. Exposure of a group-housed mouse that maintains an amicable relationship induced social approach in B6 recipient mice, as expressed by increased preference of stay in proximity and decreased scent marks relevant to those of a single-housed mouse. Nasal administration of oxytocin (OT) to stimulus mice appeared to enhance social approach in B6 recipient mice. Systemic administration of buspirone (5-HT1A agonist) to stimulus mice also increased approach in B6 recipient mice, whereas a nasal OT antagonist infusion followed by systemic buspirone injection of stimulus mice blocked this buspirone-induced approach in B6 recipient mice. BALB mice likely possess an intact signaling system as shown in B6 mice, in which the 5-HT → OT pathway is a primary modulator for social amicable signals. However, BALB mice could not exhibit signal-dependent change in approach behavior. No impairment in olfactory discrimination or approach behavior toward social stimuli was found in BALB mice. It is concluded that social cues for facilitating social approach are eliminated via the 5-HT → OT pathway, and BALB mice as a low social strain have a deficit in recognition of specific signals associated with amicability. (PsycINFO Database Record

中文翻译：

---

血清素和催产素参与调节雄性小鼠友善社交信号的神经机制：对BALB / c株友善提示的识别能力有影响。

社会信号在调节雄性小鼠之间的社会关系中起主要作用。本系列实验研究了诱导友好线索的神经机制，该线索有助于C57BL / 6（B6）和BALB / c（BALB）品系的雄性小鼠的社交活动。雄性小鼠表现出进场行为并抑制了对友好对象的领土气味标记。保持友善关系的成群饲养的小鼠的暴露在B6受体小鼠中诱发了社交方式，表现为在附近停留的喜好增加以及与单只饲养的小鼠相关的气味降低。鼻腔给予催产素（OT）刺激小鼠似乎可以增强B6受体小鼠的社交方式。向刺激性小鼠全身施用丁螺环酮（5-HT1A激动剂）也增加了B6受体小鼠的入路，而鼻OT拮抗剂输注，然后对刺激性小鼠进行全身性丁螺环酮注射，阻止了丁螺环酮诱导的B6受体小鼠入路。BALB小鼠可能具有完整的信号系统，如B6小鼠所示，其中5-HT→OT途径是社交友好信号的主要调节剂。但是，BALB小鼠不能表现出信号依赖的行为变化。在BALB小鼠中未发现嗅觉歧视或对社交刺激的接近行为受损。结论是，通过5-HT→OT途径消除了促进社交方式的社交线索，并且作为低社交品系的BALB小鼠在识别与友善性相关的特定信号时缺乏能力。