URINARY MACROMOLECULAR SUBSTANCES AS NATURAL INHIBITORS OF CALCIUM-OXALATE CRYSTAL AGGREGATION

  • 1 January 1981
    • journal article
    • research article
    • Vol. 18  (5) , 382-386
Abstract
The inhibitory effect of urinary macromolecular substances (UMM), > 10,000 MW, was studied on aggregation of calcium oxalate crystals in a crystal-seed system and a non-crystal-seed system. In both assay systems, UMM from non-stone formers showed a marked inhibitory activity on crystal aggregation; UMM from recurrent stone formers showed a weak inhibitory activity. The distinction between the 2 types of UMM was greater in the non-crystal-seed system. The macromolecular inhibitors seemed to be composed of proteins or protein complexes inasmuch as .apprx. 70-90% of the macromolecular inhibitory activity was destroyed by protein digestion with pronase. Urinary acid glycosaminoglycans, which have been considered possible inhibitors, played a small role in the inhibition of crystal aggregation.