目的探索大鼠视皮层中兴奋性神经递质受体表达和分布的发育特征以及双眼形觉剥夺(binocular form deprivation,BFD)对成年大鼠视皮层内兴奋性递质受体亚型表达和分布的影响。方法采用免疫组织化学染色和免疫印迹技术,分别对生后1~9周...目的探索大鼠视皮层中兴奋性神经递质受体表达和分布的发育特征以及双眼形觉剥夺(binocular form deprivation,BFD)对成年大鼠视皮层内兴奋性递质受体亚型表达和分布的影响。方法采用免疫组织化学染色和免疫印迹技术,分别对生后1~9周正常大鼠和自生后7周开始BFD14d后模型大鼠的视皮层中兴奋性递质受体亚型进行标记和检测。结果N-甲基-D-天冬氨酸(N-mehyl-D-aspartate,NMDA)受体亚单位NR2A(NMDA-NR2A)在大鼠未睁眼时少量表达,可塑性关键期高峰时最明显;之后表达减少,至成年期维持一定水平,BFD 14 d可以造成成年大鼠视皮层NM-DA-NR2A阳性表达减弱。NMDA-NR2B在未睁眼时表达较明显,可塑性关键期高峰时表达最多;之后表达下降稳定在成年期低水平,BFD14d可造成其在成年大鼠视皮层中表达增强。α-氨基-3-羟基-5-甲基-4-异唑丙酸受体GluR-1亚基平均分布在视皮层各层,在出生后少量表达,之后随年龄增长逐渐增强,其表达在可塑性关键期终止时达到高峰并在成年期维持较高水平,BFD14d对其在成年大鼠视皮层表达没有影响。结论由BFD诱导的NMDA-NR2A或NMDA-NR2B表达变化可能参与了成年大鼠视皮层可塑性再激活机制。展开更多
a-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors are considered to play a crucial role in synaptic plasticity in the developing visual cortex. In this study, we established a rat model of binocular form ...a-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors are considered to play a crucial role in synaptic plasticity in the developing visual cortex. In this study, we established a rat model of binocular form deprivation by suturing the rat binocular eyelids before eye-opening at postnatal day 14. During development, the decay time of excitatory postsynaptic currents mediated by a-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptors of normal rats became longer after eye- opening; however, the decay time did not change significantly in binocular form deprivation rats. The peak value in the normal group became gradually larger with age, but there was no significant change in the binocular form deprivation group. These findings indicate that binocular form deprivation influences the properties of excitatory postsynaptic currents mediated by a-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptors in the rat visual cortex around the end of the critical period, indicating that form stimulation is associated with the experience-dependent modification of neuronal synapses in the visual cortex.展开更多
文摘目的探索大鼠视皮层中兴奋性神经递质受体表达和分布的发育特征以及双眼形觉剥夺(binocular form deprivation,BFD)对成年大鼠视皮层内兴奋性递质受体亚型表达和分布的影响。方法采用免疫组织化学染色和免疫印迹技术,分别对生后1~9周正常大鼠和自生后7周开始BFD14d后模型大鼠的视皮层中兴奋性递质受体亚型进行标记和检测。结果N-甲基-D-天冬氨酸(N-mehyl-D-aspartate,NMDA)受体亚单位NR2A(NMDA-NR2A)在大鼠未睁眼时少量表达,可塑性关键期高峰时最明显;之后表达减少,至成年期维持一定水平,BFD 14 d可以造成成年大鼠视皮层NM-DA-NR2A阳性表达减弱。NMDA-NR2B在未睁眼时表达较明显,可塑性关键期高峰时表达最多;之后表达下降稳定在成年期低水平,BFD14d可造成其在成年大鼠视皮层中表达增强。α-氨基-3-羟基-5-甲基-4-异唑丙酸受体GluR-1亚基平均分布在视皮层各层,在出生后少量表达,之后随年龄增长逐渐增强,其表达在可塑性关键期终止时达到高峰并在成年期维持较高水平,BFD14d对其在成年大鼠视皮层表达没有影响。结论由BFD诱导的NMDA-NR2A或NMDA-NR2B表达变化可能参与了成年大鼠视皮层可塑性再激活机制。
基金the National Natural Science Foundation of China, No.30772350
文摘a-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors are considered to play a crucial role in synaptic plasticity in the developing visual cortex. In this study, we established a rat model of binocular form deprivation by suturing the rat binocular eyelids before eye-opening at postnatal day 14. During development, the decay time of excitatory postsynaptic currents mediated by a-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptors of normal rats became longer after eye- opening; however, the decay time did not change significantly in binocular form deprivation rats. The peak value in the normal group became gradually larger with age, but there was no significant change in the binocular form deprivation group. These findings indicate that binocular form deprivation influences the properties of excitatory postsynaptic currents mediated by a-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptors in the rat visual cortex around the end of the critical period, indicating that form stimulation is associated with the experience-dependent modification of neuronal synapses in the visual cortex.