Opposing roles for GABAA and GABAC receptors in short-term memory formation in young chicks
Opposing roles for GABAA and GABAC receptors in short-term memory formation in young chicks
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DOI：
10.1016/j.neuroscience.2004.11.033
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发表时间：
2005-01-01
期刊：
影响因子：
3.3
通讯作者：
Johnston, GAR
中科院分区：
文献类型：
--
作者：
Gibbs, ME;Johnston, GAR
抑制性神经递质GABA对雏鸡珠辨别任务的短时记忆具有抑制和增强作用。将低剂量的GABA（1-3 pmol/半球）注射到鸡前脑的多模态联合区，强烈抑制强化记忆，而较高剂量（30-100 pmol/半球）增强弱强化记忆。高剂量和低剂量的GABA对短期记忆的影响在注射时间和记忆丧失发生的时间方面都很明显。基于对GABA和选择性GABA受体拮抗剂的相对敏感性，我们认为低剂量的GABA作用于GABA（C）受体（EC 50约为1 μ M），高剂量的GABA通过GABA（A）受体起作用（EC 50约为10 μ M）。选择性GABAA受体拮抗剂荷包牡丹碱呈剂量和时间依赖性地抑制强化记忆，而选择性GABA（C）受体拮抗剂TPMPA和P4 MPA呈剂量和时间依赖性地增强弱强化记忆。GABA剂量-反应曲线对选择性拮抗剂的偏移证实了不同水平的GABA影响不同的受体亚型。很明显，GABA参与了短期记忆形成的控制，其作用，增强或抑制，取决于学习时释放的GABA水平。(c)2005由Elsevier Ltd代表IBRO出版。
The inhibitory neurotransmitter GABA has both inhibitory and enhancing effects on short-term memory for a bead discrimination task in the young chick. Low doses of GABA (1-3 pmol/hemisphere) injected into the multimodal association area of the chick forebrain, inhibit strongly reinforced memory, whereas higher doses (30-100 pmol/hemisphere) enhance weakly reinforced memory. The effect of both high and low doses of GABA is clearly on short-term memory in terms of both the time of injection and in the time that the memory loss occurs. We argue on the basis of relative sensitivities to GABA and to selective GABA receptor antagonists that low doses of GABA act at GABA(C) receptors (EC50 approximately 1 mu M) and the higher doses of GABA act via GABA(A) receptors (EC50 approximately 10 mu M). The selective GABAA receptor antagonist bicuculline inhibited strongly reinforced memory in a dose and time dependent manner, whereas the selective GABA(C) receptor antagonists TPMPA and P4MPA enhanced weakly reinforced in a dose and time dependent manner. Confirmation that different levels of GABA affect different receptor subtypes was demonstrated by the shift in the GABA dose-response curves to the selective antagonists. It is clear that GABA is involved in the control of short-term memory formation and its action, enhancing or inhibiting, depends on the level of GABA released at the time of learning. (c) 2005 Published by Elsevier Ltd on behalf of IBRO.