title: Study of the effects of different substances on the early stages of papillary stone formation.
abstract: We have studied the early stages of calcium oxalate monohydrate (COM) crystallization, mainly heterogeneous nucleation, on fixed particles. Experiments were performed using a flow system that closely simulates the human renal conditions related to COM heterogeneous nucleation. The effects of citrate, phytate, aescin and glycyrrhinic acid in the COM heterogeneous nucleation on different solid surfaces as calcium phosphate, a mixture of mucin and calcium phosphate and wax were studied. The presence of citrate at normal urinary concentrations (1.85.10(-3) M) totally inhibited the development of COM crystals only on the most hydrophobic assayed material (wax). Saponins (aescin and glycyrrhinic acid) only exhibited important inhibitory effects of COM crystallization on the hydrophobic wax substrate but in no case the formation of COM crystals was totally prevented. Phytate exerted the most remarkable effects on the heterogeneous nucleation of COM crystals, thus, when it was present at 1.43.10(-7) M, it totally prevented the development of COM crystals on the three assayed solid substrates.
authors.affiliation: Laboratory of Urochemistry, Faculty of Science, University of Balearic Islands, Palma de Mallorca, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Grases
authors.forename: L
authors.initials: L
authors.lastname: Garcia-Ferragut
authors.forename: A
authors.initials: A
authors.lastname: Costa-Bauzá
authors.forename: J G
authors.initials: JG
authors.lastname: March
mesh_terms: D002129:Calcium Oxalate / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry; D002951:Citrates / Q000737:chemistry; D003460:Crystallization; D006801:Humans; D007669:Kidney Calculi / Q000378:metabolism*; D007679:Kidney Medulla / Q000378:metabolism*; D008855:Microscopy, Electron, Scanning; D008954:Models, Biological; D009077:Mucins / Q000737:chemistry; D010833:Phytic Acid / Q000737:chemistry; D012503:Saponins / Q000737:chemistry; D014556:Urine / Q000737:chemistry; D014885:Waxes / Q000737:chemistry
chemical_list: D002130:Calcium Phosphates; D002951:Citrates; D009077:Mucins; D012503:Saponins; D014885:Waxes; D002129:Calcium Oxalate; D010833:Phytic Acid