The hippocampus is essential for learning and memory, but it also plays an important role in regulating emotional behavior, as hippocampal excitability and plasticity affect anxiety and fear. Brain synaptic plasticity may be regulated by tissue inhibitor of matrix metalloproteinase 1 (TIMP1), a known protein inhibitor of extracellular matrix (ECM), and the expression of TIMP1 in the hippocampus can be induced by neuronal excitation and various stimuli. However, the involvement of Timp1 in fear learning, anxiety, and hippocampal synaptic function remains to be established. Our study of Timp1 function in vivo revealed that Timp1 knockout mice exhibit anxiety-like behavior but normal fear learning. Electrophysiological results suggested that Timp1 knockout mice showed hyperactivity in the ventral CA1 region, but the basic synaptic transmission and plasticity were normal in the Schaffer collateral pathway. Taken together, our results suggest that deletion of Timp1 in vivo leads to the occurrence of anxiety behaviors, but that Timp1 is not crucial for fear learning.

海马体对于学习和记忆至关重要，但它在调节情绪行为方面也发挥着重要作用，因为海马体的兴奋性和可塑性会影响焦虑和恐惧。脑突触可塑性可能受到基质金属蛋白酶组织抑制剂 1 (TIMP1) 的调节，TIMP1 是一种已知的细胞外基质 (ECM) 蛋白抑制剂，神经元兴奋和各种刺激可诱导海马 TIMP1 的表达。然而，Timp1 在恐惧学习、焦虑和海马突触功能中的参与仍有待确定。我们对 Timp1 功能体内的研究表明< a i=7>Timp1 敲除小鼠表现出类似焦虑的行为，但恐惧学习正常。电生理结果提示Timp1基因敲除小鼠腹侧CA1区表现出过度活跃，但Schaffer侧支通路基本突触传递和可塑性正常。综上所述，我们的结果表明，体内删除Timp1会导致焦虑行为的发生，但Timp1 对于恐惧学习来说并不重要。