硫酸软骨素蛋白多糖对视皮层γ-氨基丁酸能神经元表达及其抑制性突触传递功能的影响❋

摘要

Obj ective :To investigate the effect of chondroitin sulfate proteoglycans (CSPGs)on GABA neurons and inhibitory synaptic transmission of visual cortex in vitro and to explore the mechanism of CSPGs on visual cortex plasticity suppression. Methods :Visual cortex neurons cultured in vitro were treated with chondroitinase ABC (ChABC).The degradation and expression of CSPGs in GABA neurons were detected by immunofluorescence.To observe synaptic function in GABA neurons, miniature inhibitory postsynaptic currents (mIPSCS)were recorded by the whole cell patch clamp.Results :CSPGs had been digested successfully after ChABC treatment on the neurons.Cell density,the amplitude and frequency of mIPSCs in GABA neurons were significantly lower than that in control.Conclusion:CSPGs promotes the expression of GABA neurons and the growth of the inhibitory synaptic transmission function,which may be one of the mechanisms of CSPGs suppressing visual cortex plasticity.%目的：：通过体外观察硫酸软骨素蛋白多糖(CSPGs)对γ-氨基丁酸(GABA)能神经元表达及其抑制性突触传递功能的影响,为探索 CSPGs 抑制视皮层可塑性的机制提供实验依据。方法：运用硫酸软骨素酶(ChABC)处理体外培养的胎鼠视皮层神经元,降解其 CSPGs 后应用免疫荧光显色检测 CSPGs 降解情况及 GABA 能神经元的表达变化,并用膜片钳检测其自发性微小性抑制性突触后电流(mIPSCs)以观察其抑制性突触传递功能变化情况。结果：0.1 U/ml ChABC 处理神经元后,CSPGs 被成功降解,GABA 能神经元细胞密度、mIPSCs 幅度和频率均显著低于正常对照组。结论：CSPGs 能促进GABA 能神经元表达及其抑制性突触传递功能的成熟,这可能是 CSPGs 抑制视皮层可塑性的作用机制之一。