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.