Selective reconfiguration of layer 4 visual cortical circuitry by visual deprivation
Selective reconfiguration of layer 4 visual cortical circuitry by visual deprivation
复制标题
DOI：
10.1038/nn1351
复制
发表时间：
2004-12-01
影响因子：
25
通讯作者：
Turrigiano, GG
中科院分区：
文献类型：
--
作者：
Maffei, A;Nelson, SB;Turrigiano, GG
发育敏感期的视觉剥夺显著改变了视觉皮质反应的特性，但这些影响背后的皮质内回路的变化却鲜为人知。在这里，我们使用大鼠初级视觉皮质的切片制备来表明，生命早期2d的先前视觉剥夺增加了第四层电路的兴奋性。脑片记录显示，视觉剥夺2d后，从出生后第15天到第17天，第4层星状锥体神经元的自发活动增加了25倍。这种作用是通过增加净兴奋性和减少净抑制性突触驱动来实现的。配对记录显示星状锥体神经元之间的兴奋性连接的幅度加倍，而抑制性连接的减少或增加取决于中间神经元的类别。当视力恢复时，这些影响发生了逆转。这种兴奋-抑制平衡的动态调整可能允许第四层内的网络在面对可变的感觉输入时保持稳定的活动水平。
Visual deprivation during a developmental sensitive period markedly alters visual cortical response properties, but the changes in intracortical circuitry that underlie these effects are poorly understood. Here we use a slice preparation of rat primary visual cortex to show that 2 d of prior visual deprivation early in life increases the excitability of layer 4 circuitry. Slice recordings showed that spontaneous activity of layer 4 star pyramidal neurons increased 25-fold after 2 d of visual deprivation between postnatal days ( P) 15 and P17. This effect was mediated by increased net excitatory and decreased net inhibitory synaptic drive. Paired recordings showed that excitatory connections between star pyramidal neurons doubled in amplitude, whereas inhibitory connections decreased or increased depending on the interneuron class. These effects reversed when vision was restored. This dynamic adjustment of the excitation-inhibition balance may allow the networks within layer 4 to maintain stable levels of activity in the face of variable sensory input.