Levels of Amino Acid Neurotransmitters during Neurogenesis and in Histotypic Cultures of Mouse Spinal Cord
Levels of Amino Acid Neurotransmitters during Neurogenesis and in Histotypic Cultures of Mouse Spinal Cord
复制标题
小鼠脊髓神经发生和组织型培养过程中氨基酸神经递质的水平
DOI：
10.1159/000064946
复制
发表时间：
2002
影响因子：
2.9
通讯作者：
E. Palacios‐Prü
中科院分区：
文献类型：
--
作者：
L. Miranda;P. Benítez;Z. Peña;R. V. Mendoza;E. Palacios‐Prü
脊髓间神经元的发育和神经元间突触连接的形成很少受到关注；研究最广泛的发展回路是运动神经元和它们所支配的肌肉之间的连接。所有运动神经元都是胆碱能神经元，而脊髓中间神经元大多是谷氨酸、甘氨酸或GABA能神经元。在这项研究中，我们提供了从胚胎12天(E)到出生后30天(P)小鼠脊髓神经发生过程中氨基酸神经递质水平的定量数据。在E12，谷氨酸、甘氨酸和牛磺酸的含量已经很高，但在E16和P3之间，它们的含量显著增加，表明在这一时期出现了最大的突触发生。在E12-E16和P3-P7两个阶段也观察到了它们含量的重要下降。这些结果表明，发育中的大脑中间神经元和运动神经元的凋亡性死亡或成熟过程中神经回路的突触细化减少了突触的数量，从而降低了神经递质的水平。这些神经递质的含量也被分析在从E13到E19胚胎制备的小鼠脊髓的原代培养中。光镜、超微结构研究和高效液相分析结果表明，来自E15-E16胚胎的培养物具有最高的组织类型特征和神经递质含量，可与原位获得的培养物相媲美。虽然甘氨酸、GABA和牛磺酸的含量约为正常值的80-90%，但天冬氨酸和谷氨酸的含量降低了约40%，这可能主要是由于感觉和棘上传入轴突终末的去传入所致。这些结果表明，从E15-E16小鼠胚胎制备的组织型脊髓培养物中可以维持固有的突触回路。脊髓的组织类型培养将成为研究许多中枢神经系统疾病中基于氨基酸的神经传递和修复策略的病理生理学的良好模型。
The development of spinal cord interneurons and the formation of interneuronal synaptic connections has received little attention; the most comprehensively studied developing circuit has been the connection between motoneurons and the muscle they innervate. All motoneurons are cholinergic whereas spinal interneurons are mostly glutamatergic, glycinergic or GABAergic neurons. In this study, we show quantitative data, obtained by high-pressure liquid chromatography (HPLC), on the levels of amino acid neurotransmitters during mouse spinal cord neurogenesis, from embryonic day (E) 12 until postnatal day (P) 30. At E12, high levels of glutamate, glycine and taurine were already detected but between E16 and P3, significant increments in their contents were observed, indicating the occurrence of maximum synaptogenesis during this period. Important reductions in their contents were also observed in two stages: between E12–E16 and P3–P7. These results suggest that the apoptotic death of interneurons and motoneurons in the developing brain or the synapse refinement of neural circuitry during maturation reduced the number of synapses, thereby decreasing the levels of neurotransmitters. The contents of these neurotransmitters were also analyzed in primary cultures of mouse spinal cord prepared from embryos between E13 and E19. As deduced from light microscopy, ultrastructural studies, as well as results from HPLC analysis, the cultures derived from E15–E16 embryos showed the highest degree of histotypic features and neurotransmitter contents comparable with those obtained in situ. Although glycine, GABA and taurine levels reached about 80–90% of normal in situ values, the contents of aspartate and glutamate were lower by about 40%, which could be mainly due to deafferentation of both sensory and supraspinal afferent axon terminals. These results indicate that intrinsic synaptic circuits can be maintained in histotypic spinal cord cultures prepared from E15–E16 mouse embryos. Histotypic cultures of the spinal cord will serve as a good model for studies on the pathophysiology of amino-acid-based neurotransmission and repair strategies in many CNS disorders.
大鼠脑和脊髓中甘氨酸受体及其信使 RNA 的异质性。
DOI：
10.1126/science.2845580
发表时间：
1988
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Akagi,H;Miledi,R
通讯作者：
Miledi,R
影响因子：
2.5
作者：
HEATH, MJS;WOMACK, MD;MACDERMOTT, AB
通讯作者：
MACDERMOTT, AB
感觉轴突由发育中的背脊髓中的局部线索引导。
DOI：
10.1242/dev.125.4.635
发表时间：
1998
期刊：
Development (Cambridge, England)
影响因子：
--
作者：
Sharma,K;Frank,E
通讯作者：
Frank,E