Suppression of NMDA receptor function using antisense DNA block ocular dominance plasticity while preserving visual responses.
Suppression of NMDA receptor function using antisense DNA block ocular dominance plasticity while preserving visual responses.
复制标题
使用反义 DNA 抑制 NMDA 受体功能可阻断眼部优势可塑性，同时保留视觉反应。
DOI：
10.1152/jn.1998.80.3.1021
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
Ramoa,AS
中科院分区：
文献类型：
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作者：
Roberts,EB;Meredith,MA;Ramoa,AS
Roberts、Elizabeth B.、M. Alex Meredith 和 Ary S. Ramoa。使用反义 DNA 抑制 NMDA 受体功能可阻断眼部优势可塑性，同时保留视觉反应。 Neurophysiol.80: 1021–1032, 1998。开创性工作表明，N-甲基-d-天冬氨酸 (NMDA) 受体通道的药理学阻断可降低眼部优势可塑性。然而，结果还表明，影响眼部优势可塑性的 NMDA 受体拮抗剂剂量会显着降低感觉反应并破坏皮质细胞的刺激选择性。因此，不可能确定 NMDA 受体阻断对视觉可塑性的影响是由于 NMDA 受体的特定作用还是由于感觉反应的减少。我们使用了另一种方法来研究这个问题。我们使用与编码 NMDA 受体 NR1 亚基的 mRNA 互补的反义寡脱氧核苷酸 (ODN) 进行了敲低实验。经过 5 天的反义（而非有义）处理后，ODN 治疗 NMDA 受体介导的突触传递相对于 α-氨基-3-羟基-5-甲基-4-异恶唑丙酸 (AMPA) 受体反应显着减少，如皮质切片制备中的全细胞膜片钳记录所示。免疫细胞化学和蛋白质印迹表明，这种 NMDA 受体介导电流的抑制是由于相对于同一动物未经处理的半球，注射部位附近的 NR1 蛋白选择性减少。相反，AMPA 受体不受反义 ODN 处理的影响，表明效果的特异性。这种治疗的另一个主要作用是降低眼部优势可塑性。在反义 ODN 治疗期间单眼剥夺 1 周的雪貂具有与未治疗的非剥夺动物中发现的相似的眼优势直方图。相比之下，用 sense ODN 治疗且单眼剥夺的雪貂具有与未经处理的单眼剥夺动物相似的眼优势直方图。对眼部优势可塑性的影响并不是由于感觉反应的破坏造成的，因为最大反应以及皮层细胞的定向和方向选择性不受治疗的影响。总之，目前的结果表明，与传统药物制剂相比，反义技术可以实现对皮质功能更具选择性的操作。这种方法的使用还为 NMDA 受体在视觉可塑性中的特定作用提供了明确的证据。
Roberts, Elizabeth B., M. Alex Meredith, and Ary S. Ramoa.Suppression of NMDA receptor function using antisense DNA blocks ocular dominance plasticity while preserving visual responses.J. Neurophysiol.80: 1021–1032, 1998. Pioneering work has shown that pharmacological blockade of theN-methyl-d-aspartate (NMDA) receptor channel reduces ocular dominance plasticity. However, the results also show that doses of NMDA receptor antagonists that have an effect on ocular dominance plasticity profoundly reduce sensory responses and disrupt stimulus selectivity of cortical cells. It is, therefore, not possible to determine whether effects of NMDA receptor blockade on visual plasticity result from a specific role of NMDA receptors or from the reduction in sensory response. We have used an alternate approach to examine this question. We performed knockdown experiments using antisense oligodeoxynucleotides (ODNs) complementary to mRNA coding the NR1 subunit of the NMDA receptor. After 5 days of antisense, but not sense, ODN treatment NMDA receptor–mediated synaptic transmission was reduced markedly relative to the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor response, as indicated by whole cell patch-clamp recordings in the cortical slice preparation. This suppression of NMDA receptor–mediated currents was due to a selective reduction in the NR1 protein near the injection site relative to the untreated hemisphere in the same animal, as indicated by immunocytochemistry and Western blotting. In contrast, AMPA receptors were not affected by the antisense ODN treatment indicating specificity of effects. Another major effect of this treatment was to decrease ocular dominance plasticity. Ferrets that were monocularly deprived 1 wk during the antisense ODN treatment had ocular dominance histograms similar to those found in untreated, nondeprived animals. In contrast, ferrets treated with sense ODN and monocularly deprived had ocular dominance histograms resembling those of untreated, monocularly deprived animals. The effects on ocular dominance plasticity did not result from a disruption of sensory responses because maximum responses as well as orientation and direction selectivity of cortical cells were not affected by the treatment. In conclusion, the present results show that antisense techniques can accomplish more selective manipulations of cortical function than is possible with traditional pharmacological agents. Use of this approach also provides unambiguous evidence for a specific role of NMDA receptors in visual plasticity.