Matrix glycosaminoglycan in urinary stones.

At first, urinary stones were classified according to their inorganic components (apatite, struvite, calcium oxalate monohydrate, calcium oxalate dihydrate and uric acid). Then, matrix glycosaminoglycan was extracted from the stones in each group and was analyzed by 2-dimensional electrophoresis. There were differences in the glycosaminoglycan content of matrices among different groups of urinary stones. The principal matrix glycosaminoglycan content consisted of hyaluronic acid in apatite and struvite stones, heparan sulfate in calcium oxalate monohydrate and uric acid stones, and hyaluronic acid and heparan sulfate in calcium oxalate dihydrate stones. We conclude that hyaluronic acid and/or heparan sulfate has an important role in urinary stone formation.