Metabolism of cystathionine, N-monoacetylcystathionine, perhydro-1,4-thiazepine-3,5-dicarboxylic acid, and cystathionine ketimine in the liver and kidney of D,L-propargylglycine-treated rats.

Experimental cystathioninuria was induced by injection of D,L-propargylglycine in rats. The novel cystathionine metabolites, N-monoacetylcystathionine (NAc-cysta), perhydro-1,4-thiazepine-3,5-dicarboxylic acid (PHTZDC), and cystathionine ketimine (CK), were identified previously in the urine of patients with cystathioninuria and D,L-propargylglycine-treated rats. In this study, we identified these compounds in the liver and kidney of D,L-propargylglycine-treated rats using liquid chromatography-mass spectrometry with an atmospheric pressure chemical ionization interface system (LC/APCI-MS) and an amino acid analyzer. The metabolism of these compounds in the liver and kidney of D,L-propargylglycine-treated rats was also studied. PHTZDC, NAc-cysta, and CK were accumulated in the rat tissues in proportion to the content of cystathionine after D,L-propargylglycine administration. The concentrations of these compounds in the liver were higher than those in the kidney, and these compounds reached maxima earlier in the liver than in the kidney.