Distribution of acidic glycosaminoglycans in the intima, media and adventitia of bovine aorta and their anticoagulant properties.

1. The constituents of acidic glycosaminoglycans in the tunica intima, media and adventitia were studied by means of an enzymatic assay with chondroitinases and by electrophoretic characterization. 2. The content of the acidic glycosaminoglycans was higher in the intima than in the adventitia based on defatted dry tissue weight. The gel filtration pattern showed that, with chondroitinase-AC, the proportion of the intact glycosaminoglycans is greater in the adventitia than in the intima. 3. Electrophoresis before and after digestion with chondroitinases indicated that the three layers contain chondroitin-4- and -6-sulfates, dermatan sulfate, heparan sulfates and hyaluronic acid. In the case of the adventitia, bands migrating like the heparin standard were also detected. 4. Paper chromatographic separation of the unsaturated disaccharides after digestion with chondroitinases revealed that the proportion of chondroitin-6-sulfate is predominant in the intima, whereas the proportion of heparan sulfates, hyaluronic acid and dermatan sulfate is one and one-half-2 times higher in the adventitia than in the intima. 5. Anticoagulant activity, measured by thrombelastography, of the acidic glycosaminoglycans in the three layers clearly indicated that the glycosaminoglycans in the adventitia possess the highest potency among the three layers. It was considered that the higher activity of the glycosaminoglycans in the adventitia is due to the relatively greater proportion of heparan sulfates and dermatan sulfate.