Figure 2.

¹³C-labeling patterns from metabolism of (A) [1-¹³C]glucose in neurons and astrocytes and (B) [1,2-¹³C]acetate in astrocytes. Black circles are ¹³C atoms, striped circles show the ¹³C-label obtained from metabolism via the PC pathway in astrocytes, white circles are ¹²C atoms. α-KG, α-ketogluratate; glu, glutamate; gln, glutamine (in astrocytes); PC, pyruvate carboxylase (in astrocytes only); PDH, pyruvate dehydrogenase; OAA, oxaloacetate; acetyl CoA, acetyl Coenzyme A; TCA, tricarboxylic acid.