Carbohydrate repression of enzyme induction in rat liver.

Experimental conditions were as follows: MgS04 , 10 pmoles; L-ornithine, 5 rmoles; glycylglycine, pH 7.5, 50 pmoles; NHIHC03, 5 Fmoles; ATP, 5 pmoles; phosphoenolpyruvate, 5 pmoles; ornithine transcarbamylase (beef liver) 17 units; phosphoenolpyruvate kinase, 513 Biicher units; frog liver carbamyl phosphate synthetase, 0.1 ml (0.825 mg); final volume, 1.00 ml; incubation for 15 minutes at 37”. N-Acetyl-L-glutamate and DLZacetoxyglutarate added in amounts as indicated. The reaction was stopped by the addition of 5 ml of 0.5 N perchloric acid and the protein removed by centrifugation. An aliquot of the supernatant solution was analyzed according to the method of Archibald (8).