Acid glycosaminoglycans in plasma. I. Determination.

Plasma glycosaminoglycans (GAG) were isolated from 10 ml of plasma by a modification of the method of Calatroni et al. (3). DE-52 anion-exchange cellulose was used in the isolation of the fraction operationally defined as free GAG. Chondroitin sulphate and heparin added to plasma were quantitatively recovered in this fraction. After proteolysis with papain the fraction operationally defined as bound GAG was isolated using anion-exchange resin AG 1 X 2. GAG were measured as hexuronate with the m-hydroxydiphenyl method of Blumenkrantz and Asboe-Hansen (7) which was superior to various modifications of the carbazole/borate carbazole procedures. In 15 healthy females and in 15 healthy males the concentrations of the free GAG (mean +/- S.D., expressed as microgram per 10 ml of plasma) were: 12.2 +/- 2.8 and 16.8 +/- 3.8 (P less than 0.001); of the bound GAG 40.4 +/- 7.7, and 40.2 +/- 11.6; and of the total GAG 52.7 +/- 9.0 and 57.0 +/- 10.4, respectively. With the isolation procedures used, plasma GAG were obtained in sufficient quantity for their electrophoretic characterization. Assay of plasma GAG can be performed with satisfactory accuracy and precision within two days by the present method. In clinical chemistry its application to the study of proteoglycan and GAG metabolism in various diseases may prove valuable.