Effects of L-alanine on ketogenesis in vitro

Alanine (5 mM) increased 14CO2 production from [1-14C]oleate by 130% and from [1-14C]butyrate by 101%. Alanine inhibited ketone-body production by 37.5% in the presence of butyrate but did not affect ketogenesis in the presence of oleate. Alanine decreased the [3-hydroxybutyrate]/[acetoacetate] ratio when either butyrate or oleate was present. The results are discussed with reference to the hypoketonaemic action of alanine in vivo.