Metabolism of ω-Amino Acids by Rat Tissues in vitro

Abstract

1. No transamination of the antifibrinolytic compounds, δ-aminocaproic acid and 4-aminomethylcyclohexanecarboxylic acid was observed with homogenates of rat liver, kidney, brain and intestinal mucosa. Also β-arninopivalic acid was not transaminated by these tissue homogenates.

2. Transamination of other ω-amino acids, β-alanine, γ-aminobutyric acid (GABA) and DL-β-aminoisobutyric acid, was catalysed by liver, kidney and brain homogenates.

3. δ-Aminovaleric acid was transaminated by liver and brain, as was ω-aminocaprylic acid by brain to a slight extent. Intestinal mucosa transaminated β-alanine to a small extent.

4. Stability constants for Schiff base formation between the ω-amino acids and pyridoxal 5′-phosphate were measured.

5. No relationship was apparent between these Schiff base stability constants and the activity of the ω-amino acids to be transaminated.