Méndez-Couz Marta, Krenzek Beate, Manahan-Vaughan Denise
Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Bochum, Germany.
Front Behav Neurosci. 2021 Apr 30;15:658686. doi: 10.3389/fnbeh.2021.658686. eCollection 2021.
Brain derived neurotropic factor (BDNF) supports neuronal survival, growth, and differentiation and is involved in forms of hippocampus-dependent and independent learning, as well as hippocampus-dependent learning. Extinction learning comprises active inhibition of no-longer relevant learned information, in conjunction with a decreased response of a previously learned behavior. It is highly dependent on context, and evidence exists that it requires hippocampal activation. The participation of BDNF in memory processing is experience-dependent. For example, BDNF has been associated with synaptic plasticity needed for spatial learning, and it is involved in acquisition and extinction learning of fear conditioning. However, little is known about its role in spatial appetitive extinction learning. In this study, we evaluated to what extent BDNF contributes to spatial appetitive extinction learning in the presence (ABA) or absence (AAA) of exposure to the acquisition context. Daily training, of BDNF-mice or their wildtype (WT) littermates, to reach acquisition criterion in a T-maze, resulted in a similar performance outcome. However, extinction learning was delayed in the AAA, and impaired in the ABA-paradigm compared to performance in WT littermates. Trial-by-trial learning analysis indicated differences in the integration of the context into extinction learning by BDNF-mice compared to WT littermates. Taken together, these results support an important role for BDNF in processes that relate to information updating and retrieval that in turn are crucial for effective extinction learning.
脑源性神经营养因子（BDNF）支持神经元的存活、生长和分化，并参与海马体依赖性和非依赖性学习以及海马体依赖性学习。消退学习包括对不再相关的已学信息进行主动抑制，同时先前习得行为的反应减少。它高度依赖于情境，并且有证据表明它需要海马体激活。BDNF在记忆处理中的参与是依赖于经验的。例如，BDNF与空间学习所需的突触可塑性有关，并且它参与恐惧条件反射的习得和消退学习。然而，关于其在空间性食欲消退学习中的作用知之甚少。在本研究中，我们评估了在存在（ABA）或不存在（AAA）获取情境暴露的情况下，BDNF在多大程度上有助于空间性食欲消退学习。对BDNF基因敲除小鼠或其野生型（WT）同窝小鼠进行每日训练，使其在T迷宫中达到习得标准，结果显示出相似的表现结果。然而，与WT同窝小鼠相比，AAA组的消退学习延迟，ABA范式组的消退学习受损。逐次试验学习分析表明，与WT同窝小鼠相比，BDNF基因敲除小鼠在将情境整合到消退学习中的方式存在差异。综上所述，这些结果支持BDNF在与信息更新和检索相关的过程中起重要作用，而这些过程反过来对有效的消退学习至关重要。
