Searles C D, Singer H S
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Brain Res. 1988 May 17;448(2):373-6. doi: 10.1016/0006-8993(88)91280-2.
gamma-Aminobutyric acid (GABA) and glutamic acid decarboxylase (GAD) activity were identified and characterized in the cholinergic neuronal cell clone NG108-15. GAD activity is similar to form A in rat brain by being temperature sensitive and independent of pyridoxal 5'-phosphate in the assay mixture. Most of the NG108-15 GAD activity is inactivated by 1 mM amino-oxyacetic acid. In contrast to NG108-15 choline acetyltransferase, GAD activity is not enhanced when cells are grown with dibutyryl cyclic AMP. The GAD activity shows a cell-density dependent increase that does not correlate with changing level of endogenous GABA. The identification of GABAergic properties in the NG108-15 clone enhances its use as a neuronal model for studies of differentiation and neurotoxicity of drugs or chemicals.
在胆碱能神经元细胞克隆NG108-15中鉴定并表征了γ-氨基丁酸（GABA）和谷氨酸脱羧酶（GAD）活性。GAD活性在温度敏感性方面与大鼠脑中的A形式相似，并且在测定混合物中不依赖于磷酸吡哆醛5'-磷酸。大部分NG108-15 GAD活性被1 mM氨氧基乙酸灭活。与NG108-15胆碱乙酰转移酶相反，当细胞用二丁酰环磷酸腺苷培养时，GAD活性不会增强。GAD活性显示出细胞密度依赖性增加，这与内源性GABA水平的变化无关。NG108-15克隆中GABA能特性的鉴定增强了其作为神经元模型用于研究药物或化学物质的分化和神经毒性的用途。
