L-谷氨酸的一种构象受限类似物，即L-α-（羧基环丙基）甘氨酸的（2S，3R，4S）异构体，在离体大鼠脊髓中比NMDA更显著地激活NMDA型受体。

A conformationally restricted analogue of L-glutamate, the (2S,3R,4S) isomer of L-alpha-(carboxycyclopropyl)glycine, activates the NMDA-type receptor more markedly than NMDA in the isolated rat spinal cord.

作者信息

Shinozaki H, Ishida M, Shimamoto K, Ohfune Y

机构信息

Tokyo Metropolitan Institute of Medical Science, Japan.

出版信息

Brain Res. 1989 Feb 20;480(1-2):355-9. doi: 10.1016/0006-8993(89)90207-2.

DOI:10.1016/0006-8993(89)90207-2

PMID:2565750

Abstract

Depolarizing actions of 4 conformationally restricted L-glutamate analogues, (2S,3S,4S) isomer (L-CCG-I), (2S,3R,4R) isomer (L-CCG-II), (2S,3S,4R) isomer (L-CCG-III) and (2S,3R,4S) isomer (L-CCG-IV) of L-alpha-(carboxycyclopropyl)-glycine (L-CCG), were investigated in the isolated rat spinal cord by extracellular recordings of potential changes of motoneurones from the ventral roots, in order to study the interaction between the conformation of glutamate and its receptor subtype. The order of the depolarizing activity was quisqualate greater than L-CCG-IV = kainate greater than NMDA greater than L-CCG-I greater than L-CCG-III greater than L-CCG-II. The depolarization caused by L-CCG-IV was effectively blocked by the NMDA antagonists and Mg2+ ions, while the L-CCG-I response was not affected by these blockers. These results suggest that the NMDA-type receptor is activated by a folded form of L-glutamate.

摘要

为了研究谷氨酸的构象与其受体亚型之间的相互作用，通过细胞外记录来自腹根运动神经元的电位变化，在离体大鼠脊髓中研究了4种构象受限的L-谷氨酸类似物，即L-α-（羧基环丙基）-甘氨酸（L-CCG）的（2S,3S,4S）异构体（L-CCG-I）、（2S,3R,4R）异构体（L-CCG-II）、（2S,3S,4R）异构体（L-CCG-III）和（2S,3R,4S）异构体（L-CCG-IV）的去极化作用。去极化活性的顺序为：quisqualate大于L-CCG-IV = 海人藻酸大于NMDA大于L-CCG-I大于L-CCG-III大于L-CCG-II。L-CCG-IV引起的去极化被NMDA拮抗剂和Mg2+离子有效阻断，而L-CCG-I的反应不受这些阻滞剂的影响。这些结果表明，NMDA型受体被L-谷氨酸的折叠形式激活。