Experimental beta-alaninuria induced by (Aminooxy)acetate

Experimental beta-alaninuria was induced in rats by injection of (aminooxy) acetate (AOA), a potent inhibitor of aminotransferases, in order to elucida te the pathogenesis of hyper-beta-alaninemia. A 27-fold increase of beta-al anine (BALA) excretion was induced by subcutaneous injection of 15 mg of AO A per kg of body weight. A 13-fold and a 9-fold increase of beta-aminoisobu tyric acid (BAIBA) and gamma-aminobutyric acid (GABA), respectively, were a lso induced simultaneously by the AOA injection. Identification of BALA and BAIBA isolated from the rat urine was performed by chromatographic and mas s spectrometric analyses. The effects of AOA injection on the tissue levels of these amino acids were also studied. Contents of BALA in the liver and kidney and GABA in the brain increased significantly in response to AOA inj ection. The present study indicates that BALA transaminase is involved in h yper-beta-alaninemia.