McGee Aaron W, Yang Yupeng, Fischer Quentin S, Daw Nigel W, Strittmatter Stephen M
Department of Neurology, Yale University School of Medicine, New Haven, CT 06520, USA.
Science. 2005 Sep 30;309(5744):2222-6. doi: 10.1126/science.1114362.
Monocular deprivation normally alters ocular dominance in the visual cortex only during a postnatal critical period (20 to 32 days postnatal in mice). We find that mutations in the Nogo-66 receptor (NgR) affect cessation of ocular dominance plasticity. In NgR-/- mice, plasticity during the critical period is normal, but it continues abnormally such that ocular dominance at 45 or 120 days postnatal is subject to the same plasticity as at juvenile ages. Thus, physiological NgR signaling from myelin-derived Nogo, MAG, and OMgp consolidates the neural circuitry established during experience-dependent plasticity. After pathological trauma, similar NgR signaling limits functional recovery and axonal regeneration.
单眼剥夺通常仅在出生后的关键期(小鼠出生后20至32天)改变视皮层中的眼优势。我们发现,Nogo-66受体(NgR)的突变会影响眼优势可塑性的终止。在NgR基因敲除小鼠中,关键期的可塑性是正常的,但它会异常持续,以至于出生后45天或120天时的眼优势与幼年时一样容易发生可塑性变化。因此,来自髓磷脂源性Nogo、MAG和OMgp的生理性NgR信号巩固了在经验依赖性可塑性过程中建立的神经回路。在病理性创伤后,类似的NgR信号会限制功能恢复和轴突再生。