Effects of inhibitory amino acids on expression of GABA_A R¦Á and glycine R¦Á1 in hypoxic rat cortical neurons during development

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• 作者：Hong  ; Qian^a ;   ; ¹ ; Yuan  ; Feng^a ;   ; ^b ;   ; ¹ ; Xiaozhou  ; He^c ; Yilin  ; Yang^c ; Jong-Hyuk  ; Sung^a ;   ; ^d ; Ying  ; Xia^a ;   ; ^e ;   ; ^{Ying.Xia@UTH.TMC.edu}
• 关键词：GABA ; Glycine ; Taurine ; Opioid ; Receptor ; Cortex ; Hypoxia
• 刊名：Brain Research
• 出版年：2011
• 出版时间：24 November 2011
• 年：2011
• 卷：1425
• 期：Complete
• 页码：1-12
• 全文大小：1228 K

文摘

Recent studies suggest that GABA and glycine are protective to mature but toxic to immature cortical neurons during prolonged hypoxia. Since the action of these inhibitory amino acids is mediated by GABA and glycine receptors, the expression of these receptors is a critical factor in determining neuronal response to GABA_A and glycine in hypoxia. Therefore, we asked whether in rat cortical neurons, 1) hypoxia alters the expression of the GABA and glycine receptors; 2) inhibitory amino acids change the course of GABA and glycine receptor expression; and 3) there are any differences between the immature and mature neurons. In cultured rat cortical neurons from day 4 (four days in vitro or DIV 4) to day 20 (DIV 20), we observed that 1) GABA_AR¦Á and GlyR¦Á1 underwent differential changes in expression during the development in vitro; 2) hypoxia for 3 days decreased GABA_AR¦Á and GlyR¦Á1 density in the neurons in-between DIV 4 and DIV 20, but did not induce a major change in immature (DIV 4) and mature (DIV 20) neurons; 3) during normoxia GABA, glycine and taurine decreased GABA_AR¦Á and GlyR¦Á1 density in the immature neurons, but had a tendency to increase the density in the mature neurons, except for taurine; 4) under hypoxia, all these amino acids decreased GABA_AR¦Á and GlyR¦Á1 density in most groups of the immature neurons with a slight effect on the mature neurons; and 5) ¦Ä-opioid receptor activation with DADLE increased GABA_AR¦Á and GlyR¦Á1 density in both the immature and mature neurons under normoxia and in the mature neurons under hypoxic condition. These data suggest that inhibitory amino acids differentially regulate the expression of GABA_A and glycine receptors in rat cortical neurons under normoxic and hypoxic conditions with major differences between the immature and mature neurons.