Reorganization of remote cortical regions after ischemic brain injury: A potential substrate for stroke recovery
Reorganization of remote cortical regions after ischemic brain injury: A potential substrate for stroke recovery
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DOI：
10.1152/jn.01143.2002
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发表时间：
2003-06-01
影响因子：
2.5
通讯作者：
Nudo, RJ
中科院分区：
文献类型：
--
作者：
Frost, SB;Barbay, S;Nudo, RJ
虽然最近的神经学研究已经阐明了中风后大脑的自我修复机制，但完整组织在恢复中所起的作用仍然不清楚。为了进一步探讨这些机制，我们使用微电极刺激技术，以检查功能重建后，大脑皮层缺血性梗死的手代表的主要运动皮层在五个成年松鼠猴。在梗死后3个月定期评估手偏好和双手的运动技能。在每只动物中，对侧手的初始梗死后运动障碍是明显的，随后在1-3个月内表现逐渐改善。梗死后12周的皮质内微刺激映射显示，在远端皮质区，腹侧运动前皮质的手代表性显着放大。相对于梗死前腹侧运动前手区域，增加范围为7.2%至53.8%，平均增加36.0 ± 20.8%。这种扩大与初级运动皮层中手表征的破坏量成正比。也就是说，更多的保留M1手区导致腹侧运动前皮质手区的扩张较少。这些结果表明，神经生理重组的远程皮质区发生在皮质损伤的反应和更大的损害相互皮质内通路，更大的可塑性在完整的地区。完整组织中的重组可能为适应性运动行为提供神经基质，并在损伤后功能恢复中发挥关键作用。
Although recent neurological research has shed light on the brain's mechanisms of self-repair after stroke, the role that intact tissue plays in recovery is still obscure. To explore these mechanisms further, we used microelectrode stimulation techniques to examine functional remodeling in cerebral cortex after an ischemic infarct in the hand representation of primary motor cortex in five adult squirrel monkeys. Hand preference and the motor skill of both hands were assessed periodically on a pellet retrieval task for 3 mo postinfarct. Initial postinfarct motor impairment of the contralateral hand was evident in each animal, followed by a gradual improvement in performance over 1-3 mo. Intracortical microstimulation mapping at 12 wk after infarct revealed substantial enlargements of the hand representation in a remote cortical area, the ventral premotor cortex. Increases ranged from 7.2 to 53.8% relative to the preinfarct ventral premotor hand area, with a mean increase of 36.0 +/- 20.8%. This enlargement was proportional to the amount of hand representation destroyed in primary motor cortex. That is, greater sparing of the M1 hand area resulted in less expansion of the ventral premotor cortex hand area. These results suggest that neurophysiologic reorganization of remote cortical areas occurs in response to cortical injury and that the greater the damage to reciprocal intracortical pathways, the greater the plasticity in intact areas. Reorganization in intact tissue may provide a neural substrate for adaptive motor behavior and play a critical role in postinjury recovery of function.