Roeder L M, Poduslo S E, Tildon J T
J Neurosci Res. 1982;8(4):671-82. doi: 10.1002/jnr.490080412.
The rates of utilization of [3-14C]-acetoacetate, [3-14C]-3-hydroxybutyrate, and [6-14C]-glucose were measured in four established cell lines from neuroblastoma of rat (B103) and mouse (N4TG1) and from rat astrocytoma (RGC6) and mouse oligodendroglia (G2620). The rates of incorporation of acetoacetate into lipid were 3-5 times higher than glucose in all cell lines. The incorporation of 3-hydroxybutyrate was similar to that of glucose. Thin-layer chromatography of the total lipid extracts showed the same relative rates of use of these substrates for synthesis of various phospholipids and neutral lipids. The rates of incorporation into neutral lipids and phosphatidylcholine were essentially linear for 12 hr; however, that into phosphatidylethanolamine was markedly higher in the second 6 hr interval than in the first. In all cases, the greatest percentage of label (35-50%) appeared in the phosphatidylcholine fraction. The distribution of label from each of the three substrates among the various lipids was similar in the glial cells, but there were marked differences in distribution of the two ketone bodies in the neuroblastoma lines. These cells also synthesized lipids that migrated to the same area on the chromatogram as cholesterol esters and free fatty acids. In three of the four cell lines the rates of oxidation were highest for glucose, intermediate for acetoacetate, and lowest for 3-hydroxybutyrate. The ratios of the rate of incorporation to the rate of oxidation were higher for ketone bodies (3.32 for 3-hydroxybutyrate and 5.29 for acetoacetate) than for glucose (0.41). This indicates that in these cells ketone bodies are directed toward lipid synthesis rather than oxidation, and glucose is preferentially used as an energy source.
在源自大鼠神经母细胞瘤（B103）、小鼠神经母细胞瘤（N4TG1）、大鼠星形细胞瘤（RGC6）和小鼠少突胶质细胞（G2620）的四种已建细胞系中，测定了[3-¹⁴C] -乙酰乙酸、[3-¹⁴C] -3-羟基丁酸和[6-¹⁴C] -葡萄糖的利用率。在所有细胞系中，乙酰乙酸掺入脂质的速率比葡萄糖高3至5倍。3-羟基丁酸的掺入情况与葡萄糖相似。总脂质提取物的薄层色谱显示，这些底物用于合成各种磷脂和中性脂质的相对速率相同。掺入中性脂质和磷脂酰胆碱的速率在12小时内基本呈线性；然而，在第二个6小时间隔内掺入磷脂酰乙醇胺的速率明显高于第一个6小时间隔。在所有情况下，最大比例的标记（35%-50%）出现在磷脂酰胆碱部分。三种底物中的每种底物在不同脂质中的标记分布在神经胶质细胞中相似，但在神经母细胞瘤细胞系中，两种酮体的分布存在明显差异。这些细胞还合成了在色谱图上迁移到与胆固醇酯和游离脂肪酸相同区域的脂质。在四个细胞系中的三个中，葡萄糖的氧化速率最高，乙酰乙酸居中，3-羟基丁酸最低。酮体的掺入速率与氧化速率之比（3-羟基丁酸为3.32，乙酰乙酸为5.29）高于葡萄糖（0.41）。这表明在这些细胞中，酮体用于脂质合成而非氧化，葡萄糖优先用作能量来源。
