The Brain Body Center, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612, USA.
J Neuroendocrinol. 2012 Jun;24(6):874-86. doi: 10.1111/j.1365-2826.2012.02301.x.
Paternal behaviour and pair-bond formation are defining characteristics of social monogamy. However, in comparison to pair-bonding, the endocrine factors associated with the male care of young are not well studied. In the present study, plasma concentrations of oxytocin, vasopressin and corticosterone (CORT) were measured in reproductively naïve male prairie voles as a function of exposure to an infant or control manipulations (i.e. handling or exposure to a wooden dowel). Plasma oxytocin concentrations were transiently elevated within 10 min of pup exposure. Although plasma CORT concentration typically increases after handling, after 10 min of pup exposure, the concentration of plasma CORT was not increased, suggesting an attenuation of CORT release by pup exposure. Group differences in the concentrations of plasma hormones were no longer detected at 20 or 60 min after treatment. These patterns of rapid change in the concentrations of plasma oxytocin and CORT were observed in both juvenile and adult males but not detected after control procedures. Plasma vasopressin, assessed only in adult males, did not vary as a function of pup exposure or other manipulations. In the paraventricular nucleus of the hypothalamus, pup exposure also increased activation (as assessed by the measurement of c-Fos) of neurones that stained for either oxytocin or vasopressin, whereas it decreased c-Fos expression in neurones stained for corticotrophin-releasing hormone. In addition, brief pup exposure (20 min) facilitated subsequent partner preference formation when alloparental males and pup attackers were considered as a group. In the context of other studies, these data support the hypothesis that neuroendocrine changes associated with male alloparental behaviour are related to those implicated in pair-bonding.
父性行为和伴侣形成是社会一夫一妻制的定义特征。然而，与伴侣关系相比，与雄性照顾幼崽相关的内分泌因素尚未得到很好的研究。在本研究中，测量了生殖初的雄性草原田鼠暴露于婴儿或对照操作（即处理或暴露于木制销钉）时的催产素、血管加压素和皮质酮（CORT）的血浆浓度。暴露于幼崽后 10 分钟内，血浆催产素浓度短暂升高。尽管处理后通常会增加血浆 CORT 浓度，但暴露于幼崽 10 分钟后，血浆 CORT 浓度并未增加，表明幼崽暴露会减弱 CORT 的释放。处理后 20 或 60 分钟后，不再检测到血浆激素浓度的组间差异。在幼崽和成年雄性中均观察到了血浆催产素和 CORT 浓度的这种快速变化模式，但在对照程序后未检测到。仅在成年雄性中评估的血浆血管加压素，其浓度既不受幼崽暴露的影响，也不受其他操作的影响。在视前核中，幼崽暴露还增加了对催产素或血管加压素染色的神经元的激活（通过 c-Fos 的测量来评估），而对促皮质素释放激素染色的神经元的 c-Fos 表达则降低。此外，当将所有雄性和幼崽攻击者视为一组时，短暂的幼崽暴露（20 分钟）促进了随后的伴侣偏好形成。在其他研究的背景下，这些数据支持了这样的假设，即与雄性亲代行为相关的神经内分泌变化与那些与伴侣关系相关的变化有关。
