Physiologisches Institut, University of Tübingen, Gmelinstr. 5, 72076 Tübingen, Germany.
Neurochem Res. 2012 Nov;37(11):2562-8. doi: 10.1007/s11064-012-0857-3. Epub 2012 Aug 10.
Metabolism of short-chain fatty acids (SCFA) in the brain, particularly that of acetate, appears to occur mainly in astrocytes. The differential use has been attributed to transport, but the extent to which transmembrane movement of SCFA is mediated by transporters has not been investigated systematically. Here we tested the possible contribution of monocarboxylate transporters to SCFA uptake by measuring fluxes with labelled compounds and by following changes of the intracellular pH in Xenopus laevis oocytes expressing the isoforms MCT1, MCT2 or MCT4. All isoforms mediated significant transport of acetate. Formate, however, was transported only by MCT1. The contribution of MCT1 to SCFA transport was determined by using phloretin as a high-affinity inhibitor, which allowed a paired comparison of oocytes with and without active MCT1.
脑内短链脂肪酸（SCFA）的代谢，特别是乙酸盐的代谢，似乎主要发生在星形胶质细胞中。这种差异被归因于运输，但 SCFA 的跨膜运动在多大程度上是由转运蛋白介导的，尚未系统研究。在这里，我们通过测量标记化合物的通量和监测表达 MCT1、MCT2 或 MCT4 同工型的非洲爪蟾卵母细胞内 pH 的变化，来测试单羧酸转运蛋白对 SCFA 摄取的可能贡献。所有同工型都能显著转运乙酸盐。然而，甲酸盐只能被 MCT1 转运。使用根皮苷作为高亲和力抑制剂来确定 MCT1 对 SCFA 转运的贡献，这允许对具有和不具有活性 MCT1 的卵母细胞进行配对比较。
