Effect of Vitamin B 6 Deficiency on Hepatic Transaminase and Cysteine Desulfhydrase Systems

Summary

1. The glutamic-pyruvic, glutamine-pyruvic, and gluamine-phenylpyruvic reactions, and cysteine desulfhydrase activity were determined in homogenates of livers of vit. B₆-deficient rats and vit. B₆-supplemented control rats. 2. Glutamic-pyruvic tansaminase activity was considerable reduced in livers of the deficient animals, while the glutamine-pyruvic and glutamine-phenylpyruvic reactions proceeded at approximately equal rates in control and deficient rats. 3. Cysteine desulfhydrase activity was markedly reduced in the livers of the deficient animals. Addition of pyridoxal phosphate to homogenates of the livers of the deficient animals resulted in restoration of most of the cysteine desulf-hydrase activity. 4. The implications of these findings in terms of the participation of vit. B₆ in the glutamine-α-keto acid reactions are discussed.