Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Boulevard Juriquilla 3001, Querétaro, 76230, Mexico.
Silvio O. Conte Center for Oxytocin and Social Cognition, Center for Translational Social Neuroscience, Department of Psychiatry and Behavioral Sciences, Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd., Atlanta, GA, 30329, United States.
Behav Brain Res. 2021 Jun 25;408:113264. doi: 10.1016/j.bbr.2021.113264. Epub 2021 Mar 26.
Around 5 % of mammals are socially monogamous and both parents provide care to the pups (biparental, BP). Prairie voles are socially monogamous rodents extensively used to understand the neurobiological basis of pair bond formation and the consequences that the absence of one parent has in the offspring. Pair bonding, characterized by selective affiliation with a sexual partner, is facilitated in prairie voles by mating for 6 h or cohabitation without mating for 24 h. It was previously shown that prairie voles raised by their mother alone (monoparental, MP) show delayed pair bond formation upon reaching adulthood. In this study we evaluated the effects of BP and MP care provided on the offspring's development, ability to detect olfactory cues, preference for sexually relevant odors, display of sexual behavior, as well as the rewarding effects of mating. We also measured dopamine and serotonin concentration in the nucleus accumbens (ventral striatum) and dorsal striatum after cohabitation and mating (CM) to determine if differences in these neurotransmitters could underlie the delay in pair bond formation in MP voles. Our data showed that MP voles received less licking/grooming than BP voles, but no developmental differences between groups were found. No differences were found in the detection and discrimination of olfactory cues or preference for sexually relevant odors, as all groups innately preferred opposite sex odors. No differences were found in the display of sexual behavior. However, CM induced reinforcing properties only in BP males, followed by a preference for their sexual partner in BP but not MP males. BP males showed an increase in dopamine turnover (DOPAC/DA and HVA/DA) in the nucleus accumbens in comparison to MP voles. No differences in dopamine, serotonin or their metabolites were found in the dorsal striatum. Our results indicate that MP voles that received less licking behavior exhibit a delay in pair bond formation possibly because the sexual interaction is not rewarding enough.
大约 5%的哺乳动物是社会一夫一妻制的，并且父母双方都为幼崽提供照顾（双亲，BP）。草原田鼠是社会一夫一妻制的啮齿动物，被广泛用于理解伴侣关系形成的神经生物学基础以及父母一方缺失对后代的影响。配对结合，其特征是与性伴侣的选择性联系，在草原田鼠中通过交配 6 小时或同居 24 小时而不交配来促进。以前的研究表明，由母亲单独抚养的草原田鼠（单亲，MP）在成年后表现出配对结合形成的延迟。在这项研究中，我们评估了 BP 和 MP 对后代发育的影响，检测嗅觉线索的能力，对性相关气味的偏好，性行为的表现，以及交配的奖励作用。我们还测量了交配后（CM）伏隔核（腹侧纹状体）和背侧纹状体中的多巴胺和 5-羟色胺浓度，以确定这些神经递质的差异是否可以解释 MP 田鼠配对结合形成的延迟。我们的数据表明，MP 田鼠接受的舔舐/梳理比 BP 田鼠少，但两组之间没有发现发育差异。在嗅觉线索的检测和辨别或对性相关气味的偏好方面没有发现差异，因为所有组都天生喜欢异性的气味。在性行为的表现方面没有发现差异。然而，CM 仅在 BP 雄性中诱导出强化特性，随后在 BP 但不在 MP 雄性中表现出对其性伴侣的偏好。与 MP 田鼠相比，BP 雄性的伏隔核中的多巴胺周转率（DOPAC/DA 和 HVA/DA）增加。在背侧纹状体中未发现多巴胺、5-羟色胺或其代谢物的差异。我们的结果表明，接受较少舔舐行为的 MP 田鼠表现出配对结合形成的延迟，可能是因为性相互作用不够有奖励作用。
