6月9日，《神经科学杂志》发表了中国科学院上海生命科学研究院神经科学研究所树突发育与神经环路形成研究组的最新成果。该项工作由博士研究生何姗和博士后马骏在于翔研究员的指导下共同完成。
环境因素对脑发育至关重要。运用对新生小鼠进行丰富环境饲养作为研究环境因素影响脑发育的行为范式，何姗和马骏通过电生理与生物化学等检测手段发现，与普通条件饲养的小鼠相对比，两周的丰富环境饲养可加速小鼠海马CA1脑区椎体神经元伽马氨基丁酸能和谷氨酸能突触传递的发育,表现在微小突触后伽马氨基丁酸或谷氨酸能电流幅度或频率的增加，以及突触后受体和骨架蛋白表达水平的上调。
更重要的是，丰富环境饲养可以促进伽马氨基丁酸在早期神经环路发育过程中从兴奋性向抑制性的转变。综上所述，对新生小鼠进行早期丰富环境饲养可以加速海马脑区神经环路的成熟。
该工作得到了科学院、科技部和国家自然科学基金的资助。(生物谷Bioon.net)
生物谷推荐原文出处：
The Journal of Neuroscience doi:10.1523/JNEUROSCI.6375-09.2010
Early Enriched Environment Promotes Neonatal GABAergic Neurotransmission and Accelerates Synapse Maturation
Shan He,1,2 * Jun Ma,1 * Na Liu,1,2 and Xiang Yu1
1Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China, and 2Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
Environmental stimulation is critical for brain development. Here, we report that natural stimulation through enriched environment (EE) rearing during the first 2 weeks of mouse postnatal development promotes GABAergic neurotransmission and accelerates maturation of GABAergic and glutamatergic synapses. Using whole-cell recordings from CA1 pyramidal neurons in acute hippocampal slices, we found that EE-reared mice exhibited higher amplitude of miniature GABAergic postsynaptic currents (mGPSCs) at 1 week of postnatal development, as well as accelerated transition of GABA action from excitation to inhibition, compared with mice reared under standard housing conditions. This enhanced GABAergic synaptic transmission persisted until the end of the second postnatal week, when GABA mostly acts as an inhibitory neurotransmitter. Consistent with these electrophysiological results, we observed elevated levels of GABAA receptors and the K+-Cl– cotransporter KCC2. Similarly, increased levels of excitatory synaptic components, including NMDA and AMPA receptors and the scaffolding protein PSD95, were detected in synaptosomal fractions from the forebrain/hippocampus of EE-reared mice during the first two postnatal weeks. Functional increase in glutamatergic synaptic transmission, as measured by increased amplitude of miniature and spontaneous EPSCs, was also detected during the second postnatal week. Together, these results demonstrate that early environmental stimulation through EE rearing enhances early postnatal GABAergic neurotransmission, which is known to play important trophic functions in many aspects of neural development.
