State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China.
Integr Zool. 2024 Jul;19(4):694-709. doi: 10.1111/1749-4877.12768. Epub 2023 Oct 7.
Pheromones and olfactory communication play vital roles in sex recognition and mate choice in rodents. Asian house rats (Rattus tanezumi) (RT) often startle easily, making behavioral measurements difficult to carry out accurately in the laboratory. Here, the behavioral and olfactory preferences of the female RT between males and females were not observed using a conventional two-choice device; we then explored the neuro-immunohistochemical evidence in the brains of RT females. We found that male urine elicited significantly higher c-fos expression in the accessory olfactory system and sex-related brain regions in females than female urine did. On the other hand, the differences of volatile compounds and major urinary proteins (MUPs) in both voided urine and preputial glands (PGs) of the RT were detected using gas chromatography-mass spectrometer, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, isoelectric focusing electrophoresis, and liquid chromatography-electrospray ionization mass spectrometry. We found that PG-derived 1-(4,5-dihydro-2-thiazolyl)-ethanone and total MUPs were more abundant in males versus females, suggesting these sexually divergent components might activate the female's accessory olfactory system. In conclusion, the neuro-immunohistochemical evidence indicated that potential sex pheromones might exist in RT; however, the strength of the chemical signal might be too weak to cause behavioral responses in females.
信息素和嗅觉通讯在啮齿动物的性别识别和配偶选择中起着至关重要的作用。亚洲家鼠（Rattus tanezumi）（RT）通常很容易受到惊吓，使得在实验室中难以准确进行行为测量。在这里，我们使用传统的双选择装置观察到雌性 RT 对雄性和雌性的行为和嗅觉偏好；然后，我们探讨了雌性 RT 大脑中的神经免疫组织化学证据。我们发现，雄性尿液在雌性的副嗅系统和与性别相关的大脑区域中引起的 c-fos 表达明显高于雌性尿液。另一方面，使用气相色谱-质谱联用仪、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、等电聚焦电泳和液相色谱-电喷雾电离质谱检测了 RT 排遗尿液和包皮腺（PG）中挥发性化合物和主要尿蛋白（MUP）的差异。我们发现，PG 衍生的 1-（4,5-二氢-2-噻唑基）-乙酮和总 MUP 在雄性中比雌性更丰富，表明这些性别差异的成分可能激活了雌性的副嗅系统。总之，神经免疫组织化学证据表明，潜在的性信息素可能存在于 RT 中；然而，化学信号的强度可能太弱，无法引起雌性的行为反应。
