Huber K M, Sawtell N B, Bear M F
Department of Neuroscience, Howard Hughes Medical Institute, Brown University, Providence, RI 02912, USA.
Neuropharmacology. 1998 Apr-May;37(4-5):571-9. doi: 10.1016/s0028-3908(98)00050-1.
The effects of brain-derived neurotrophic factor (BDNF) were investigated on synaptic transmission and two forms of activity-dependent synaptic plasticity, long-term potentiation (LTP) and long-term depression (LTD), in visual cortex slices prepared from young (P21 -28) rats. The slices treated for 2-5 h in BDNF showed no difference from control slices when a 'strong' tetanus was used (theta-burst stimulation) to elicit a maximal level of LTP but displayed significantly greater synaptic potentiation in response to a 'weak' (20 Hz) tetanus. The BDNF-treated slices also showed significantly less LTD in response to a 1 Hz tetanus. Thus, BDNF treatment alters the relationship between stimulation frequency and synaptic plasticity in the visual cortex, shifting the modification threshold to the left. The effects of BDNF on LTP and LTD induction may be attributed to the significant enhancement of synaptic responses that was observed during conditioning stimulation. These data suggest that one role of BDNF during development of the visual cortex may be to modulate the properties of synaptic plasticity, enhancing synaptic strengthening and reducing synaptic weakening processes which contribute to the formation of specific synaptic connections.
在从幼年（出生后21 - 28天）大鼠制备的视皮层切片中，研究了脑源性神经营养因子（BDNF）对突触传递以及两种形式的活动依赖性突触可塑性——长时程增强（LTP）和长时程抑制（LTD）的影响。当使用“强”强直刺激（theta爆发刺激）来引发最大水平的LTP时，用BDNF处理2 - 5小时的切片与对照切片没有差异，但在响应“弱”（20Hz）强直刺激时表现出明显更强的突触增强。用BDNF处理的切片在响应1Hz强直刺激时也表现出明显更少的LTD。因此，BDNF处理改变了视皮层中刺激频率与突触可塑性之间的关系，将修饰阈值向左移动。BDNF对LTP和LTD诱导的影响可能归因于在条件刺激期间观察到的突触反应的显著增强。这些数据表明，BDNF在视皮层发育过程中的一个作用可能是调节突触可塑性的特性，增强突触强化并减少有助于形成特定突触连接的突触减弱过程。
