Dreyfus H, Ferret B, Harth S, Gorio A, Durand M, Freysz L, Massarelli R
J Neurosci Res. 1984;12(2-3):311-22. doi: 10.1002/jnr.490120218.
Previous experiments have shown that the addition of a mixture of gangliosides to the growth medium induced morphological changes in primary neuronal cultures, producing especially a trophic effect and a sprouting of neurites (neuritogenesis). The study reported here examined the changes of some biochemical parameters that paralleled the morphological modifications of cultured neurons from chick brain hemispheres treated with gangliosides. Neurons cultured from 3 to 7 days in the presence of various concentrations of a purified mixture or of single-species of gangliosides (GM1, GD1a, GT1b) revealed that these glycolipids were easily incorporated into the cells as a function of their exogenous concentrations. Incubation of neurons with N-acetyl-D-[U-14C]mannosamine showed a final labeling of all endogenous cellular and exogenous incorporated gangliosides; however, the radioactivity recovered decreased as a function of the number of sialic acid units of the exogenously added gangliosides. The treatment of neuronal cells from 3 to 7 days in culture with a mixture of 10(-8) M and 10(-5) M gangliosides led to the following observations on some neurochemical parameters: no effect on the influx of choline and dopamine; no effect on the spontaneous choline efflux, whereas the K+-provoked one is abolished; decrease of the spontaneous and K+-stimulated release of dopamine; no effect on the spontaneous release of GABA for 10(-8) M gangliosides but an increase of both spontaneous and K+-provoked release for 10(-5) M gangliosides. The data suggest that the possible insertion of gangliosides into the neuronal membranes may imply structural modifications that may influence enzymatic activities, neurotransmitter transport, and finally, some nerve cell mechanisms.
先前的实验表明，在生长培养基中添加神经节苷脂混合物可诱导原代神经元培养物发生形态变化，尤其产生营养作用并使神经突发芽（神经突形成）。本文报道的研究检测了一些生化参数的变化，这些变化与用神经节苷脂处理的鸡脑半球培养神经元的形态改变平行。在存在不同浓度的纯化混合物或单一神经节苷脂（GM1、GD1a、GT1b）的情况下培养3至7天的神经元表明，这些糖脂很容易根据其外源浓度掺入细胞中。用N-乙酰-D-[U-14C]甘露糖胺孵育神经元显示所有内源性细胞和外源掺入的神经节苷脂最终都被标记；然而，回收的放射性随着外源添加神经节苷脂的唾液酸单元数量的增加而减少。用10^(-8)M和10^(-5)M神经节苷脂混合物处理培养3至7天的神经元细胞，对一些神经化学参数有以下观察结果：对胆碱和多巴胺的内流无影响；对自发胆碱外流无影响，而钾离子激发的胆碱外流被消除；多巴胺的自发释放和钾离子刺激的释放减少；对于10^(-8)M神经节苷脂，对GABA的自发释放无影响，但对于10^(-5)M神经节苷脂，自发释放和钾离子激发的释放均增加。数据表明，神经节苷脂可能插入神经元膜中可能意味着结构修饰，这可能影响酶活性、神经递质转运，最终影响一些神经细胞机制。
