ABSTRACT
Optimal enzyme/substrate ratios were studied to estimate the activity of lysosomal glycosaminoglycan (GAG) hydrolases in homogenate and supernatant fractions of liver tissue. The modified procedures enabled, without any loss in sensitivity, to decrease the amount of biological material in samples on estimation of hyaluronidase, beta-glucuronidase and N-acetyl-beta-D-hexosaminidase; concentration of substrate was also decreased in mixtures containing hexosaminidase. Under conditions of experimental cirrhosis total and, especially, non-sedimented activities of GAG-hydrolases as well as the rate of the enzymes penetration through lysosomal membranes were increased in liver tissue.
Subject(s)
Acetylglucosaminidase/metabolism , Glucuronidase/metabolism , Glycosaminoglycans/metabolism , Hexosaminidases/metabolism , Hyaluronoglucosaminidase/metabolism , Liver/enzymology , Lysosomes/enzymology , Animals , Kinetics , Male , RatsSubject(s)
Hydroxyproline/blood , Colorimetry/methods , Free Radicals , Humans , Peptides/metabolism , Protein BindingABSTRACT
Isoenzyme B of N-acetyl- beta-D-glucosaminidase prevailed in rat blood serum, while the A form of the enzyme dominated in liver tissue as shown by DEAE cellulose chromatography. The serum isoenzyme A was distinct from the corresponding tissue type in chromatographic properties. In acute intoxication of liver tissue with CCl4 the tissue isoenzyme A, characteristic for the liver tissue of intact animals, was found in blood serum. Occurrence of the tissue isoenzyme A in blood serum might reflect the pathological state of the tissue; an increase in content of the enzyme in blood plasma appears to develop due to liberation of the enzyme from tissues.
