INCREASE IN CYSTATHIONINE CONTENT IN RAT-LIVER MITOCHONDRIA AFTER D,L-PROPARGYLGLYCINE ADMINISTRATION

Intraperitoneal administration of D,L-propargylglycine to rats resulte d in an increase in the cystathionine content of whole liver and liver mitochondria. Cystathionine in mitochondria was identified by amino a cid analysis, thin layer chromatography, high-voltage paper electropho resis and liquid chromatography-mass spectrometry. The cystathionine c ontent of whole liver was 5.37 +/- 1.59 mu mol per g of fresh liver at 14 h after the administration of 50 mg of D,L-propargylglycine per kg of body weight, while 0.07 +/- 0.02 mu mol of cystathionine per g of fresh liver was detected in the control rats. The cystathionine conten t of liver mitochondria from both groups of rats was 9.40 +/- 1.20 and 0.19 +/- 0.04 nmol of cystathionine per mg of protein, respectively. The mitochondrial cystathionine increased dose-dependently with the in crease of D,L-propargylglycine administered. The increase was proporti onal to the time after the administration up to 12 h, and then decreas ed. The increase of cystathionine in the liver mitochondria was linear ly proportional to that in the whole liver. These results suggest that cystathionine in liver mitochondria is in an equilibrium with that in the cytosol.