1) A heteropolysaccharide that is similar in structure to heparin. It accumulates in individuals with mucopolysaccharidosis.

2) Similar to heparin but with some L-iduronic acid residues.

3) Heparitin Sulfate. A glycosaminoglycan, structurally similar to heparin but with more N-acetyl groups and fewer O- and N-sulfate groups. Occurs in the liver, aorta, and lung. Accumulates in several mucopolysaccharidoses.