Bayerl Doris S, Kaczmarek Veronika, Jurek Benjamin, van den Burg Erwin H, Neumann Inga D, Gaßner Barbara M, Klampfl Stefanie M, Bosch Oliver J
Department of Behavioural and Molecular Neurobiology, University of Regensburg, 93053 Regensburg, Germany.
Horm Behav. 2016 Mar;79:18-27. doi: 10.1016/j.yhbeh.2015.12.003. Epub 2015 Dec 30.
Recent studies using V1b receptor (V1bR) knockout mice or central pharmacological manipulations in lactating rats highlighted the influence of this receptor for maternal behavior. However, its role in specific brain sites known to be important for maternal behavior has not been investigated to date. In the present study, we reveal that V1bR mRNA (qPCR) and protein levels (Western blot) within either the medial preoptic area (MPOA) or the medial-posterior part of the bed nucleus of the stria terminalis (mpBNST) did not differ between virgin and lactating rats. Furthermore, we characterized the effects of V1bR blockade via bilateral injections of the receptor subtype-specific antagonist SSR149415 within the MPOA or the mpBNST on maternal behavior (maternal care under non-stress and stress conditions, maternal motivation to retrieve pups in a novel environment, maternal aggression) and anxiety-related behavior in lactating rats. Blocking V1bR within the MPOA increased pup retrieval, whereas within the mpBNST it decreased pup-directed behavior, specifically licking/grooming the pups, during the maternal defense test. In addition, immediately after termination of the maternal defense test, V1bR antagonism in both brain regions reduced nursing, particularly arched back nursing. Anxiety-related behavior was not affected by V1bR antagonism in either brain region. In conclusion our data indicate that V1bR antagonism significantly modulates different aspects of maternal behavior in a brain region-dependent manner.
最近使用V1b受体（V1bR）基因敲除小鼠或对哺乳期大鼠进行中枢药理学操作的研究突出了该受体对母性行为的影响。然而，其在已知对母性行为很重要的特定脑区中的作用迄今为止尚未得到研究。在本研究中，我们发现，未生育大鼠和哺乳期大鼠在内侧视前区（MPOA）或终纹床核内侧后部（mpBNST）内的V1bR mRNA（定量PCR）和蛋白质水平（蛋白质免疫印迹法）并无差异。此外，我们通过在MPOA或mpBNST内双侧注射受体亚型特异性拮抗剂SSR149415来阻断V1bR，以此研究其对哺乳期大鼠母性行为（非应激和应激条件下的母性关怀、在新环境中找回幼崽的母性动机、母性攻击行为）和焦虑相关行为的影响。在MPOA内阻断V1bR可增加找回幼崽的行为，而在mpBNST内阻断V1bR则会在母性防御试验期间减少针对幼崽的行为，特别是舔舐/梳理幼崽的行为。此外，在母性防御试验结束后立即观察发现，两个脑区内的V1bR拮抗作用均会减少哺乳行为，尤其是弓背哺乳行为。两个脑区内的V1bR拮抗作用均未影响焦虑相关行为。总之，我们的数据表明，V1bR拮抗作用以脑区依赖的方式显著调节母性行为的不同方面。
