Effects of acidic glycosaminoglycans in human aortic inner and outer layers on partial thromboplastin time.

(1) Acidic glycosaminoglycans (AGAG) were prepared from the inner and outer layers of human aorta and fractionated by Dowex 1-X2 columns. The anticoagulant activity of the fractionated AGAG was measured by the partial thromboplastin time. (2) Heparan sulfates were the main AGAG in the 1.25 M NaCl fraction and were more abundant in the outer layer than in the inner. Likewise, there was more dermatan sulfate in the outer layer. (3) The AGAG in the outer layer showed much greater anticoagulant activity than those in the inner layer, both in the 1.25 M and 1.75 M NaCl fractions. (4) Anticoagulant activity was attributed to the heparan sulfates in the 1.25 M fraction and to the dermatan sulfate in the 1.75 M fraction.