摘要
背景弱视的形成与视皮层中谷氨酸受体关系密切，研究已证实弱视大鼠视皮层代谢性谷氨酸受体1（mGluRl）表达下降，但弱视形成后，mGluRl在视皮层突触传递效能中的作用如何尚不清楚。目的探讨mGluRl在单眼形觉剥夺弱视大鼠视皮层V1区神经元突触传递效能中的作用。方法将16只14日龄SD大鼠按随机数字表法随机分为正常对照组和形觉剥夺组，每组8只。形觉剥夺组大鼠于出生后14d缝合左眼上下睑建立单眼形觉剥夺弱视模型，模型建立后饲养31d处死2个组大鼠，制备大鼠400“m厚视皮层切片并在人工脑脊液中孵育。将视皮质切片分为3，5-二羟苯甘氨酸（DHPG）组、LY367385＋DHPG组、2-甲基-6-（苯乙炔）吡啶盐酸盐（MPEP）＋DHPG组及LY367385＋MPEP＋DHPG组，分别在人工脑脊液中添加相应药物，应用细胞外微电极记录法进行电生理学实验，记录视皮层V1区神经元场兴奋性突触后电位（fEPSP）。结果将药物处理前fEPSP斜率值设定为100％，DHPG处理后，正常对照组和形觉剥夺组视皮层神经元fEPSP斜率值分别增至（136．4±17．3）％和（120．7±12．8）％，2者比较差异均有统计学意义（t=2．280，P〈O．05）。LY367385和MPEP处理后，正常对照组fEPSP斜率值分别为（114．9±9．3）％和（112．6±15．3）％，形觉剥夺组分别为（107．3±6．0）％和（110．1±4．1）％，均明显低于相应单纯DHPG处理的fEPSP斜率值，差异均有统计学意义（正常对照组：t=2．641、2．915，均P〈0．05；形觉剥夺组：t=2．410、2．372，均P〈0．05）。LY367385联合MPEP处理后，正常对照组fEPSP斜率值为（104．5±2．2）％，形觉剥夺组为（102．8±14．9）％，均明显低于相应单纯DHPG处理的fEPSP斜率值，差异均有统计学意义（t=3．080、2．306，均P〈0．05）。结论mGluRl在单眼弱视大鼠视皮层神经元的突触传递中发挥的作用较正常大鼠减弱，mGluRl和mGluR5共同参与视皮层神经元突触的传递，2个亚型受体的作用基本相同。
Background The formation of amblyopia is closely associated with glutamate receptors of visual cortex, and researches determined that the expression of metabolic glutamate receptor 1 （mGluR1） in the visual cortexof amblyopic rats is down-regulated. However,the effect of mGluR1 on synaptic transmission of neurons in the visual cortex is unclear. Objective This study was to investigate the role of mGluR1 in the synaptic transmission efficiency of neurons in the primary visual cortex of monocular form-deprivated rats. Methods Sixteen 14-day-old SD rats were randomly divided into normal control group and form-deprivation group,with 8 rats in each group. The eyelids of the left eyes were sutured to establish the monocular form-deprivation models in the rats of the form- deprivation group,and the visual cortex slices were prepared until 31 days after modeling and incubated in artificial cerebrospinal fluid with 3,5-dihydroxyphenylglycine （ DHPG ）, LY367385 ＋ DHPG, 2-methyl-6-（ phenyl acetylene ） pyridine hydrochloride（MPEP） ＋DHPG and LY367385＋MPEP＋DHPG,respectively. The field excitatory postsynaptic potential （fEPSP） of neurons in the visual cortex of V1 area was detected by extracellular microelectrode recording. The use and care of the animals followed the statement for the Use of Animals in Ophthalmic and Vision Research. Results The slope value before drug treatment was set as 100% ,the fEPSP-slopes of the normal control group and the form-deprivation group were increased to （ 136.4 ±17.3 ） % and （ 120. 7± 12.8 ） % after DHPG induction with significant difference between the two groups （ t = 2. 280 ; P〈0. 05 ）. The fEPSP-slopes of the normal control group were （ 114. 9±9.3 ） % and （ 112. 6± 15.3 ） % after LY367385 and MPEP treatment, and those of the form-deprivation group were （ 107.3±6. 0） % and （ 110. 1 ±4. 1 ） % ,which were significantly lower than those after DHPG induction （ normal control group：t = 2. 641,2. 915 ; both at P 〈 0.05 ; form-deprivation group： t = 2. 410,2. 372 ; both at P 〈 O. 05 ）. The fEPSP-slopes of the normal control group and the form-deprivation group were （ 104.5 ±2.2） % and （ 102. 8 ±14. 9 ）% after LY367385＋MPEP treatment,which were lower than that after DHPG induction （t= 3. 080,2. 306 ;both at P〈0.05）. Conclusions The effect of mGluR1 on the synaptic transmission of neurons in the visual cortex weakens after monocular form-deprivation in rats. Both mGluR1 and mGluR5 participate in the neuronic synaptic transmission on visual cortex area and appear to be equivalent contribution.
出处
《中华实验眼科杂志》
CAS
CSCD
北大核心
2016年第4期293-297,共5页
Chinese Journal Of Experimental Ophthalmology
基金
河南省教育厅2011年医学科技攻关项目（2011A320012）
新乡医学院2014年度研究生科研创新支持计划项目（YJSCX20432Y）
