Increased Expression of the Growth-Associated Protein 43 Gene in the Sensorimotor Cortex of the Macaque Monkey After Lesioning the Lateral Corticospinal Tract
Increased Expression of the Growth-Associated Protein 43 Gene in the Sensorimotor Cortex of the Macaque Monkey After Lesioning the Lateral Corticospinal Tract
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DOI：
10.1002/cne.22121
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发表时间：
2009-10-20
影响因子：
2.5
通讯作者：
Isa, Tadashi
中科院分区：
文献类型：
--
作者：
Higo, Noriyuki;Nishimura, Yukio;Isa, Tadashi
为了研究脊髓损伤后大脑皮质功能恢复的神经基础，我们测量了参与突触发芽过程的生长相关蛋白43 （growth-associated protein 43, GAP-43）的表达。我们测定了单侧侧皮质脊髓束（l-CST）损伤猕猴颈髓C4/C5水平感觉运动皮质区GAP-43 mRNA的表达水平，并将其与完整猕猴相应区域的表达水平进行了比较。受伤的猴子在手术后的第一个月内恢复了手指的灵活性，并且在初级运动区（M1）的II-III层，双侧的GAP-43 mRNA水平增加。双标记分析表明，GAP-43 mRNA在兴奋性神经元中表达强烈，而在抑制性中间神经元中表达较少。双侧M1第V层的中型（面积500- 1000亩）和大型锥体细胞（面积100 - 1000亩）的表达也有所增加。损伤对侧M1区GAP-43 mRNA的表达在恢复早期比恢复晚期更明显。此外，在对侧腹侧运动前区和初级体感觉区，GAP-43 mRNA在II-III层均增加。这些结果表明，在I-CST损伤后，GAP-43参与了时间依赖性和脑区域特异性的塑性变化。这种表达模式暗示可塑性变化不仅发生在M1，也发生在广泛的联想皮质网络，包括腹侧前运动区和初级感觉区。[j]中国生物医学工程学报，2009。(C) 2009 Wiley-Liss, Inc。
To investigate the neural basis for functional recovery of the cerebral cortex following spinal cord injury, we measured the expression of growth-associated protein 43 (GAP-43), which is involved in the process of synaptic sprouting. We determined the GAP-43 mRNA expression levels in the sensorimotor cortical areas of macaque monkeys with a unilateral lesion of the lateral corticospinal tract (l-CST) at the C4/C5 level of the cervical cord and compared them with the levels in the corresponding regions of intact monkeys. Lesioned monkeys recovered finger dexterity during the first months after surgery, and the GAP-43 mRNA levels increased in layers II-III in primary motor areas (M1), bilaterally. Double-labeling analysis of the lesioned monkeys showed that GAP-43 mRNA was expressed strongly in excitatory neurons but only rarely in inhibitory interneurons. Expression also increased in the medium-sized (area, 500-1,000 mu m(2)) and large pyramidal cells (area, >1,000 mu m(2)) in layer V of the bilateral M1. The increased expression of GAP-43 mRNA in the M1 contralateral to the lesion was more prominent during the early recovery stage than during the late recovery stage. In addition, GAP-43 mRNA increased in layers II-III of both the contralesional ventral premotor area and the primary somatosensory area. These results suggest that GAP-43 is involved in time-dependent and brain region-specific plastic changes after I-CST lesioning. The expression patterns imply that plastic changes occur not only in M1 but also in the broad associative cortical network, including the ventral premotor and primary sensory areas. J. Comp. Neurol. 516:493-506, 2009. (C) 2009 Wiley-Liss, Inc.