早期聽覺傳入神經阻斷後NMDA受體的表現情形

Expression of N-methyl-D-Aspartate Receptor after Early Auditory Deafferentation

廖文輝(Wen-Huei Laio) ； Remi Marianowski ； Patrice Tran Ba Huy

《中華民國耳鼻喉科醫學雜誌》 34卷2期 (1999/03) Pp. 137-143

https://doi.org/10.6286/1999.34.2.137

摘要

背景：建立早期聽覺傳入神經阻斷的動物模式，以模擬重度聽障新生兒的聽覺腦幹神經系統情形。利用分子生物醫學技術－原位雜交法，來探測N-methyl-D-aspartate（NMDA）受體在大白鼠聽覺腦幹神經系統內細胞層次的表現情形。
方法：新生鼠（Sprague-Dawley種），於出生後第7天起至第16天，連續10天，進行皮下注射耳毒性藥物（Amikacin），每隻每公斤500毫克，此為實驗組；每胎留下半數為正常組。收集兩組的冰凍腦幹組織，依出生後第9天至第15天、第30天、第45天及第60天等各5個標本數。經冷凍切片及特殊處理後，以放射性同位素硫（S）標記的寡醣核苷酸為探針，進行NMDA受體的次成分（NR1及NR2A-2D）的原位雜交法分析。
結果：大白鼠的聽覺腦幹神經系統內，耳蝸核（cochlear nucleus）及下丘核（inferior colliculus），其NMDA受體的表現情形，經原位雜交法分析，實驗組與對照組比較，有明顯地表現減少情形。
結論：NMDA受體在正常的大白鼠聽覺腦神經系統內，其各次成分於出生後的發育過程中，有明顯動態性表現的情形，因而推論NMDA受體於大白鼠聽覺神經元的正常發育過程中可能佔有重要的調控角色。

關鍵字

NMDA受體 ； 覺傳入神經阻斷 ； 原位雜位法

並列摘要

Background: Congenital profound deafness is a distressing condition which disturbs the cognitive development as well as the behavior of children. In this study we tried to set up an animal model of the early auditory deafferentation for further research. At the same time, we monitored the N-methyl-D-aspar-tate (NMDA) receptor subunits expression in the brain stem by in situ hybridization.
Methods: Litters of Spraque-Dawley rats were divided into two groups. In the ototoxic deafened group, Amikacin was administered subcutaneously at a dosage of 500 mg/kg from the 7th post-natal day (P7) to P16. The other half rats acted as the control group. The rats were sacrificed and decapitated at the following days: P9-P15, P30, P45, and P60. The brains were rapidly removed, immediately frozen in isopenthane, and kept at -80° C. Coronal sections (14 μm) of brain stem were cut in a cryostat at -20° C. Then the in situ hybridization wad performed with 3' (S35) labeled oligonucleotide probes designed to detect the NMDA receptor subunits (NR1, NR2A-2D).
Result: In the rat auditory brainstem, the cochlear nucleus and inferior colliculus, the expression of NMDA receptor subunits decreased after the early auditory deafferentation.
Conclusion: The NMDA receptor subunits expression has the dynamic change during the post-natal period. It suggests the NMDA receptor may play an important role in the early development of auditory nerve system.

並列關鍵字

N-methyl-D-aspartate receptor ； aunditory deafferentation ； in situ hybridization