Dörner R, Ballanyi K, Schlue W R
Institut für Zoologie, Universität Düsseldorf, F.R.G.
Brain Res. 1990 Jul 16;523(1):111-6. doi: 10.1016/0006-8993(90)91642-t.
The effects of glutaminergic agonists on neuropile glial cells and on Retzius neurones in the central nervous system (CNS) of the leech, Hirudo medicinalis were investigated using double-barrelled ion-sensitive microelectrodes. In both types of cells, bath-application of L-glutamate (Glu), kainate (Ka) and quisqualate (Qui) elicited substantial membrane depolarizations which were accompanied by increases of the intracellular Na+ activity aiNa and by concomitant decrease of the intracellular K+ activity aiK. In the glial cells, these alterations of aiNa and aiK were preceded by a transient decrease of aiNa and an increase of aiK upon administration of Ka and Qui. In both glial cells and neurones, N-methyl-D-aspartate (NMDA) did not affect Em, aiK and aiNa. As found for Ka, the neuronal as well as the glial responses to glutaminergic agonists persisted during inhibition of synaptic transmission in high Mg2+, low Ca2+ solutions. The results indicate that leech neuropile glial cells have a Ka/Qui-preferring non-NMDA glutamate receptor similar to that in the Retzius neurones.
使用双管离子敏感微电极研究了谷氨酰胺能激动剂对医用水蛭中枢神经系统（CNS）中神经毡胶质细胞和Retzius神经元的影响。在这两种类型的细胞中，浴加L-谷氨酸（Glu）、海人藻酸（Ka）和quisqualate（Qui）都会引起大量的膜去极化，同时伴随着细胞内Na⁺活性aiNa的增加和细胞内K⁺活性aiK的相应降低。在胶质细胞中，在施用Ka和Qui后，aiNa和aiK的这些变化之前会出现aiNa的短暂降低和aiK的增加。在胶质细胞和神经元中，N-甲基-D-天冬氨酸（NMDA）均不影响Em、aiK和aiNa。正如对Ka的研究发现，在高Mg²⁺、低Ca²⁺溶液中抑制突触传递期间，神经元和胶质细胞对谷氨酰胺能激动剂的反应仍然存在。结果表明，水蛭神经毡胶质细胞具有与Retzius神经元中类似的对Ka/Qui偏好的非NMDA谷氨酸受体。
