해마신경세포의 성장에 미치는 GABA의 흥분성 영향

Abstract

This study was designed to evaluate whether the activation of the GABA receptor had an excitatory effect on the early developing hippocampal neurons. Thus, primary culture of hippocampal neurons was prepared from rat embryos at embryonic day 17∼18, In the groups treated with glutamate (25 μM), NMDA (25 μM) or kainate (25 μM), the neuronal development did not change, compared to the control group, however, the development was prominently inhibited by AMPA (25 μM). APV (10 μM), an NMDA receptor angagonist did not affect the development of the neurons, but non-NMDA receptor angagonist, CNQX (10 μM), suppressed the neuronal development. Kainate receptor selective blocker, NS-102 (10 μM), inhibited the neuronal growth, but AMPA receptor selective blocker, 6-chlorkynurenic acid (10 μM), had no effect. GABA (25 μM) stimulated the neuronal development, while GABA antagonist, bicuculline (10 μM), had an opposite effect. Nifedipine, voltage-dependent Ca2+ channel blocker, inhibited the neuronal development in almost all the groups treated with glutamate or GABA receptor agonists. These results indicate that GABA has an excitatory effect on early developing hippocampal neurons and that the role of kainate receptor in the effect of glutamate is greater than that of NMDA receptor in early development of cultured hippocampal neurons.