Brain metabolism is in principle similar to the biochemical processes which take place in all
cells and organs. However, specialization of the different cell types in the brain, i.e. neurons or glial
cells, adds a complexity which differs from other organs. In this chapter, a detailed outline of the
metabolic processes providing the basis for brain energy and ammonia metabolism is provided. It also
contains information regarding the effects on energy metabolism of a dysfunctional ammonia
homeostasis such as that related to hepatic encephalopathy (HE). Moreover, methodological tools by
which these metabolic processes may be studied experimentally such as PET as well as tissue and cell
preparations are reviewed.
Keywords: Brain; Metabolism; Ammonia; Neuron; Astrocyte.
