Taylor Stacie L, Stanek Lisa M, Ressler Kerry J, Huhman Kim L
Center for Behavioral Neuroscience, Neuroscience Institute, Georgia State University, Atlanta, GA 30302-5030, USA.
Behav Neurosci. 2011 Dec;125(6):911-20. doi: 10.1037/a0026172.
Syrian hamsters readily form dominant-subordinate relationships under laboratory conditions. Winning or losing in agonistic encounters can have striking, long-term effects on social behavior, but the mechanisms underlying this experience-induced behavioral plasticity are unclear. The present study tested the hypothesis that changes in brain-derived neurotrophic factor (BDNF) may at least in part mediate this plasticity. Male hamsters were paired for 15-min using a resident-intruder model, and individuals were identified as winners or losers on the basis of their behavior. BDNF was examined with in situ hybridization 2 hr after treatment during the consolidation period of emotional learning. Losing animals had significantly more BDNF mRNA in the basolateral (BLA) and medial (MeA) nuclei of the amygdala when compared with winning animals as well as novel cage and home cage controls. Interestingly, winning animals had significantly more BDNF mRNA in the dentate gyrus of the dorsal hippocampus than did losing animals, novel, and home cage controls. No conflict-related changes in BDNF mRNA were observed in several other regions including the bed nucleus of the stria terminalis and central amygdala. Next, we demonstrated that K252a, a Trk receptor antagonist, significantly reduced the acquisition of conditioned defeat when administered within the BLA. These data support a model in which BDNF-mediated plasticity within the BLA supports learning of submission or subordinate social status in losing animals, whereas BDNF-mediated plasticity within the hippocampus may instantiate aspects of winning such as control of a territory in dominant animals.
叙利亚仓鼠在实验室条件下很容易形成主导-从属关系。在争斗性遭遇中获胜或失败会对社会行为产生显著的长期影响，但这种经验诱导的行为可塑性背后的机制尚不清楚。本研究检验了一种假设，即脑源性神经营养因子（BDNF）的变化可能至少部分介导了这种可塑性。使用定居者-入侵者模型将雄性仓鼠配对15分钟，并根据它们的行为将个体确定为赢家或输家。在情绪学习巩固期，处理后2小时用原位杂交法检测BDNF。与获胜动物以及新笼子和家笼对照组相比，失败动物杏仁核基底外侧（BLA）和内侧（MeA）核中的BDNF mRNA显著更多。有趣的是，获胜动物背侧海马齿状回中的BDNF mRNA比失败动物、新笼子和家笼对照组显著更多。在包括终纹床核和中央杏仁核在内的其他几个区域未观察到与冲突相关的BDNF mRNA变化。接下来，我们证明，Trk受体拮抗剂K252a在BLA内给药时显著降低了条件性失败的习得。这些数据支持了一个模型，其中BLA内BDNF介导的可塑性支持失败动物对顺从或从属社会地位习性的学习，而海马体内BDNF介导的可塑性可能体现获胜的方面，例如优势动物对领地的控制。
