Abstract:
Vasopressin and oxytocin are well known and evolutionarily ancient modulators of social behavior. The distribution and relative densities of vasopressin and oxytocin receptors are known to modulate the sensitivity to these signaling molecules. Comparative work is needed to determine which neural networks have been conserved and modified over evolutionary time, and which social behaviors are commonly modulated by nonapeptide signaling. To this end, we used receptor autoradiography to determine the distribution of vasopressin 1a and oxytocin receptors in the Southern giant pouched rat (Cricetomys ansorgei) brain, and to assess the relative densities of these receptors in specific brain regions. We then compared the relative receptor pattern to 23 other species of rodents using a multivariate ANOVA. Pouched rat receptor patterns were strikingly similar to hamsters and voles overall, despite the variation in social organization among species. Uniquely, the pouched rat had dense vasopressin 1a receptor binding in the caudate-putamen (i.e., striatum), an area that might impact affiliative behavior in this species. In contrast, the pouched rat had relatively little oxytocin receptor binding in much of the anterior forebrain. Notably, however, oxytocin receptor binding demonstrated extremely dense binding in the bed nucleus of the stria terminalis, which is associated with the modulation of several social behaviors and a central hub of the social decision-making network. Examination of the nonapeptide system has the potential to reveal insights into species-specific behaviors and general themes in the modulation of social behavior.
摘要:
血管加压素和催产素是众所周知的,在进化上古老的社会行为调节剂。已知加压素和催产素受体的分布和相对密度调节对这些信号分子的敏感性。需要进行比较工作,以确定哪些神经网络在进化时间内得到了保守和修改,以及哪些社会行为通常由非肽信号调节。为此,我们使用受体放射自显影来确定南部巨大袋鼠(Cricetomysansorgei)大脑中加压素1a和催产素受体的分布,并评估这些受体在特定大脑区域的相对密度。然后我们使用多变量ANOVA将相对受体模式与23种其他啮齿动物进行比较。袋鼠受体模式与仓鼠和田鼠的整体相似,尽管物种之间的社会组织存在差异。独特的,袋装大鼠在尾状壳核中具有密集的加压素1a受体结合(即,纹状体),可能会影响该物种的亲属关系行为的区域。相比之下,袋装大鼠在大部分前脑前脑中的催产素受体结合相对较少。值得注意的是,然而,催产素受体结合在终末纹的床核中表现出极其密集的结合,它与多种社会行为的调制有关,并且是社会决策网络的中心枢纽。对非肽系统的检查有可能揭示对物种特定行为和社会行为调节中的一般主题的见解。