Fig. 3.

Some examples of ¹³C-labelling patterns in brain metabolism, based on results with singly labelled substrates (Gallagher et al., 2009; Tyson et al., 2003). Turquoise fills indicate ¹³C atoms. Yellow highlight indicates the metabolic pathway by which ¹³C-labelled lactate is processed via the TCA cycle, emerging as ¹³C-labelled glutamate or ¹³C-labelled glutamine that can be recovered in brain microdialysates. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)