Patch-clamp studies of glutamate receptor channels in cultured hippocampal neurons.

培养的海马神经元中谷氨酸受体通道的膜片钳研究。

• 批准号: 60480114
• 负责人: OZAWA Seiji
• 金额: $ 4.1万
• 依托单位: Gunma University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60480114/
• 关键词: Glutamate receptor channel; Kainate; Quinolinate; NMDA; Cultured hippocampal neuron; Patch-clamp technique; Single-channel current; グルタミン酸受容体; 培養海馬錐体細胞

It is widely accepted that glutamate is the principal neurotransmitter that mediates excitatory synaptic transmission in the mammalian central nervous system. Furthermore, evidence is accumulating that cellular events caused by glutamate play a key role in the induction of plastic changes in the efficacy of the synaptic transmission. Therefore it is important to clarify changes in the membrane properties induced by glutamate and related excitatory amino acids (EAAS) in the central neurons. In this study, we examined the properties of receptor channels activated by EAAs in cultured rat hippocampal neurons. The whole-cell and outside-out configurations of the patch-clamp technique were used to study macroscopic and single-channel currents. The results are summarized as follows:1. The ions permeant through glutamate receptor channels are Na^+, K^+ and Ca^<2+>.2. Glutamate activated single channel events of several different levels with single-channel conductances 40-50 pS and < 20 pS. The … More large (40-50 pS) and small (< 20 pS) events were due to the activation of N-methyl-D-aspartate (NMDA) and non-NMDA (quisqualate, or kainate) receptors, respectively.3. Mg^<21> in the extracellular solution markedly suppressed the opening of NMDA channels in the potential range more negative than -40 mV.4. The NMDA receptor channel was highly permeable to Ca^<2+>. The value Of P_<ca>/P_<na> was 6.2 according to the constant field equation. The permsability sequence of the NMDA channel among the divalent cations was determined to be Ba^<2+>(1.2) > Ca^<2+>(1.0) > Sr^<2+>(0.8) > Mn^<2+>(O.3)>> Mg^<2+>(<O.02).5. Quinolinate, an excitotoxic brain metabolite, selectively activated NMDA receptor channels.6. Kainate receptor channels were classified into two types. The Ca^<2+> permeability of the type 1 receptor was very low. In contrast, the type 2 receptor showed relatively high permeability to Ca^<2+> (P_<ca>/P_<na>=2.3). Study is needed to characterize single-channel properties of the type 2 kainate receptor. Less

人们普遍认为，谷氨酸是哺乳动物中枢神经系统中介导兴奋性突触传递的主要神经递质。此外，越来越多的证据表明，由谷氨酸引起的细胞事件在诱导突触传递效能的可塑性变化中起着关键作用。因此，弄清谷氨酸及其相关兴奋性氨基酸（EAAS）在中枢神经元中引起的膜性质变化具有重要意义。在本研究中，我们研究了eaa在培养的大鼠海马神经元中激活的受体通道的特性。膜片钳技术的全细胞和外向外结构被用来研究宏观和单通道电流。研究结果总结如下：1。通过谷氨酸受体通道的离子有Na^+、K^+和Ca^<2+>.2。谷氨酸激活了多个不同水平的单通道事件，单通道电导为40-50 pS和< 20 pS，较大（40-50 pS）和较小（< 20 pS）的事件分别是由于n-甲基- d -天冬氨酸（NMDA）和非NMDA（半氨酸或盐酸盐）受体的激活。胞外溶液Mg^<21>显著抑制NMDA通道的开放，其电位范围比-40 mv更负。NMDA受体通道对Ca^<2+>具有高通透性。根据常场方程，P_<ca>/P_<na>的值为6.2。测定了二价阳离子间NMDA通道的通度顺序为Ba^<2+>(1.2) > Ca^<2+>(1.0) > Sr^<2+>(0.8) > Mn^<2+>(O)。3) > > Mg ^ < 2 + > (< O.02)。5。喹啉酸盐是一种兴奋性脑代谢物，选择性地激活NMDA受体通道。盐酸盐受体通道分为两类。1型受体的Ca^<2+>通透性很低。相比之下，2型受体对Ca^<2+>的通透性相对较高（P_< Ca >/P_<na>=2.3）。需要进一步研究2型盐酸盐受体的单通道特性。少

项目成果

Ozawa, S. et al.: "Cation permeability change caused by L-glutamate in cultured rat hippocampal neurons." Brain Research. 443. 85-94 (1988)

Ozawa, S. 等人：“培养的大鼠海马神经元中 L-谷氨酸引起的阳离子渗透性变化。”

Ozawa, S. et al.: "Three types of voltage-dependent calcium current in cultured rat hippocampal neurons." Brain Research. 495. 329-336 (1989)

Ozawa, S. 等人：“培养的大鼠海马神经元中三种类型的电压依赖性钙电流。”

Ozawa,S.et al.: "Cation permeability change caused by L-glutamate in cultured rat hippoocampal neurons." Brain Research. 443. 85-94 (1988)

Ozawa,S.et al.：“培养的大鼠海马神经元中 L-谷氨酸引起的阳离子渗透性变化。”

小澤瀞司: "培養神経細胞のグルタミン酸受容体" 代謝. 26. 13-22 (1989)

Satoshi Ozawa：“培养神经元中的谷氨酸受体”代谢。26. 13-22 (1989)

Iino,M.et al.: "Permeation of calcium through excitatory amino acid receptor channels in cultured rat hippocampal neurones." Journal of Physiology(London). in press.

Iino,M.等人：“培养的大鼠海马神经元中钙通过兴奋性氨基酸受体通道的渗透。”