Welker E, Rao S B, Dörfl J, Melzer P, van der Loos H
Institute of Anatomy, University of Lausanne, Switzerland.
J Neurosci. 1992 Jan;12(1):153-70. doi: 10.1523/JNEUROSCI.12-01-00153.1992.
We investigated experience-dependent regulation of neuronal activity in the whisker-to-barrel pathway of the adult mouse using the autoradiographic deoxyglucose (DG) method. Animals were placed in the Lausanne whisker stimulator, and three of their whisker follicles were passively stimulated for a period of 1, 2, or 4 d. After this period, mice received a dose of DG and were placed in a cage containing a pile of wooden sticks. Mice that underwent the same procedure except the passive stimulation served as controls. Patterns of stimulus-dependent DG uptake were studied in the somatosensory cortex and in the trigeminal sensory brainstem complex. DG uptake in the barrels corresponding to the passively stimulated whiskers was lower than in controls. This decrease was present throughout the radial extent of a barrel column and was observed in all passively stimulated animals. Quantitative analysis confirmed these observations and, furthermore, showed a statistically significant decrease in DG uptake in barrels neighboring the passively stimulated ones. In half of the animals, the brainstem nuclei showed a decreased DG uptake in the representation of the passively stimulated whiskers, whereas in the other animals the pattern of DG uptake was as in controls. We propose that the signs of cortical plasticity are due to a mechanism that operates in layer IV and functions as a gate for peripheral sensory activity to enter cortical circuitry.
我们使用放射自显影脱氧葡萄糖（DG）方法，研究了成年小鼠胡须到桶状通路中神经元活动的经验依赖性调节。将动物置于洛桑胡须刺激器中，被动刺激其三个胡须毛囊1、2或4天。在此期间后，给小鼠注射一剂DG，并将其置于装有一堆木棍的笼子里。除被动刺激外，接受相同程序的小鼠作为对照。在体感皮层和三叉神经感觉脑干复合体中研究了刺激依赖性DG摄取模式。与被动刺激的胡须相对应的桶状区域中的DG摄取低于对照组。这种减少在桶状柱的整个径向范围内都存在，并且在所有被动刺激的动物中都观察到。定量分析证实了这些观察结果，此外，还显示与被动刺激的桶状区域相邻的桶状区域中DG摄取有统计学意义的减少。在一半的动物中，脑干核在被动刺激的胡须的代表区域显示DG摄取减少，而在其他动物中，DG摄取模式与对照组相同。我们提出，皮质可塑性的迹象是由于一种在IV层起作用的机制，该机制作为外周感觉活动进入皮质回路的闸门。
