Examination of co-release hypothesis of glutamate and GABA at the hippocampal mossy fiber synapse

海马苔藓纤维突触谷氨酸和 GABA 共释放假说的检验

• 批准号: 17300125
• 负责人: KAMIYA Haruyuki
• 金额: $ 10.27万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17300125/
• 关键词: HIPPOCAMPUS; SYNAPTIC TRANSMISSION; GLUTAMATE; GABA; GABA

Recent studies suggested that hippocampal mossy fiber terminals of young rodents release GABA in addition to glutamate. In this study, we examined the exact cellular mechanisms underlying co-release of GABA and glutamate using whole cell recordings in hippocampal slices as well as immunohistochemistry in young mice (P14-P21). Strong stimulus to the granule cell layer of dentate gyrus reliably elicited IPSCs in CA3 neurons in the presence of glutamate receptor antagonists 10μM CNQX and 25μM D-AP5. These putative monosynaptic IPSCs were abolished by further application of GABA_A receptor antagonist 100μM picrotoxin. In contrast, weak stimulus to the granule cell layer never elicited IPSCs in the presence of CNQX and D-AP5. The differential effects of the glutamate receptor antagonists between strong and weak stimuli suggested that some additional cellular components were recruited by the strong stimulus of the granule cell layer. We also examined localization of GABA and the GABA-synthesizing enzyme GAD immunohistochemically, and found that GABA and GAD were expressed weakly at the mossy fiber terminals. However, vesicular GABA transporter VGAT was not detected within the terminals. These results suggested that strong stimulus to the granule cell layer causes apparent monosynaptic IPSCs by stimulating inhibitory interneurons in addition to mossy fibers, and the hippocampal mossy fiber terminals themselves may not release GABA in young mouse.

最近的研究表明，幼年啮齿动物的海马苔藓纤维末端除了谷氨酸之外还释放 GABA。在这项研究中，我们利用幼年小鼠海马切片的全细胞记录以及免疫组织化学检查了 GABA 和谷氨酸共同释放的确切细胞机制。 (P14-P21)。在存在的情况下，对齿状回颗粒细胞层的强烈刺激可靠地引发了 CA3 神经元中的 IPSCs。谷氨酸受体拮抗剂10μM CNQX和25μM D-AP5。这些假定的单突触IPSC通过进一步应用GABA_A受体拮抗剂100μM印防己毒素而被消除，相反，在CNQX和D-AP5存在的情况下，对颗粒细胞层的弱刺激从未引起IPSC。谷氨酸受体拮抗剂在强刺激和弱刺激之间的不同作用表明，一些额外的细胞成分我们还通过免疫组织化学检查了 GABA 和 GABA 合成酶 GAD 的定位，发现 GABA 和 GAD 在苔藓纤维末端表达较弱，但未检测到囊泡 GABA 转运蛋白 VGAT。这些结果表明，除了苔藓外，对颗粒细胞层的强烈刺激还通过刺激抑制性中间神经元引起明显的单突触 IPSC。纤维，而年轻小鼠的海马苔藓纤维末端本身可能不会释放 GABA。

项目成果

Calcium store and presynaptic plasticity in the hippocampus

海马体的钙储存和突触前可塑性

• 发表时间: 2007
• 作者: Kamiya;H.
• 通讯作者: H.

Localization of diacylglycerol lipase-alpha around postsynaptic spine suggests close proximity between production site of an endocannabinoid, 2-arachidonoyl-glycerol, and presynaptic cannabinoid CB1 receptor

二酰基甘油脂肪酶-α 定位于突触后棘周围，表明内源性大麻素、2-花生四烯酰甘油和突触前大麻素 CB1 受体的产生位点非常接近

• 发表时间: 2006
• 期刊: Journal of Neuroscience 26・18
• 作者: Yoshida;T.;et al.
• 通讯作者: et al.

カルシウムストアと海馬プレシナプス可塑性

钙储存和海马突触前可塑性

• 发表时间: 2007
• 作者: Y. He;R. Himenol;H. Liu;H. Yokota;and Z. Sun;神谷温之
• 通讯作者: 神谷温之

Evidence against GABA release from glutamatergic mossy fiber terminals in the developing hippocampus

发育中的海马体中谷氨酸能苔藓纤维末端释放 GABA 的证据

• 发表时间: 2007
• 期刊: Journal of Neuroscience 27
• 作者: Uchigashima;M. ;et. al.
• 通讯作者: et. al.

Rab3 GTPase-activating protein regulates synaptic transmission and plasticity through the inactivation of Rab3

• DOI: 10.1073/pnas.0600304103
• 发表时间: 2006-06-27
• 期刊: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• 影响因子: 11.1
• 作者: Sakane, Ayuko;Manabe, Shinji;Sasaki, Takuya
• 通讯作者: Sasaki, Takuya