Bear M F, Colman H
Center for Neural Science, Brown University, Providence, RI 02912.
Proc Natl Acad Sci U S A. 1990 Dec;87(23):9246-9. doi: 10.1073/pnas.87.23.9246.
The lateral geniculate nucleus relays visual information from the retina to cortex. One well-known anatomical consequence of monocular deprivation during early postnatal development is a shrinkage of neurons in the lamina of the lateral geniculate nucleus that receive input from the deprived eye. This is thought to reflect the competition of afferents subserving the two eyes, possibly at the level of the visual cortex. We find that blockade of N-methyl-D-aspartate receptors in kitten visual cortex disrupts this process of binocular competition. These data provide direct evidence that postsynaptic activation of cortical neurons is required for competitive changes in lateral geniculate cell size and suggest a role for N-methyl-D-aspartate receptors in anatomical as well as physiological plasticity in the mammalian visual system.
外侧膝状体核将视觉信息从视网膜传递至皮层。出生后早期发育阶段单眼剥夺的一个著名解剖学后果是，外侧膝状体核中接受来自被剥夺眼输入的层内神经元出现萎缩。这被认为反映了为双眼服务的传入神经之间的竞争，可能发生在视觉皮层水平。我们发现，阻断小猫视觉皮层中的N-甲基-D-天冬氨酸受体可破坏这种双眼竞争过程。这些数据提供了直接证据，表明皮层神经元的突触后激活对于外侧膝状体细胞大小的竞争性变化是必需的，并提示N-甲基-D-天冬氨酸受体在哺乳动物视觉系统的解剖学以及生理学可塑性中发挥作用。
