Neurotrophins have been intensively studied and have multiple roles in the brain. Neurotrophins are first synthetized as proneurotrophins and then cleaved intracellularly and extracellularly. Increasing evidences demonstrate that proneurotrophins and mature neurotrophins exerts opposing role in the central nervous system. In the present review, we explore the role of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT3), and neurotrophin 4 (NT4) and their respective proform in cellular processes related to learning and memory. We focused on their roles in synaptic activity and plasticity in the brain with an emphasis on long-term potentiation, long-term depression, and basal synaptic transmission in the hippocampus and the temporal lobe area. We also discuss new findings on the role of the Val66Met polymorphism on the BDNF propeptide on synaptic activity.

中文翻译：

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Neurotrophins和proneurotrophins：专注于大脑的突触活动和可塑性。

神经营养蛋白已被深入研究，并在大脑中具有多种作用。首先将神经营养蛋白合成为神经营养蛋白，然后在细胞内和细胞外裂解。越来越多的证据表明，神经营养素和成熟的神经营养素在中枢神经系统中发挥相反的作用。在本综述中，我们探讨了神经生长因子（NGF），脑源性神经营养因子（BDNF），神经营养蛋白3（NT3）和神经营养蛋白4（NT4）的作用以及它们各自在与学习和记忆相关的细胞过程中的作用。我们专注于它们在大脑中突触活动和可塑性中的作用，重点在于海马和颞叶区域的长期增强，长期抑郁和基础突触传递。