Defective urinary crystallization inhibition and urinary stone formation
AUTOR(ES)
Carvalho, Mauricio, Lulich, Jody P., Osborne, Carl A., Nakagawa, Yasushi
FONTE
International braz j urol
DATA DE PUBLICAÇÃO
2006-06
RESUMO
INTRODUCTION: Nephrocalcin (NC) is a glycoprotein produced in the kidney and inhibits calcium oxalate crystal formation. It has been separated into 4 isoforms (A, B, C, and D) and found that (A + B) are more abundant than (C + D) in urine of healthy subjects, but the reverse is seen in human urine of kidney stone patients. To further examine the role of this protein in inhibition of urinary crystallization, nephrocalcin isoforms were purified from 2 genetically pure dog species. MATERIALS AND METHODS: We studied healthy Beagles, known to be non-stone forming dogs, and Mini-Schnauzers, known to be calcium oxalate stone formers. NC was isolated and purified from each group. Urinary biochemistry and calcium oxalate crystal growth inhibition were measured. RESULTS: Specific crystal growth inhibition activity was significantly higher in non-stone forming dogs (9.79 ± 2.25 in Beagles vs. 2.75 ± 1.34 of Mini-Schnauzers, p < 0.005). Dissociation constants toward calcium oxalate monohydrate were 10-fold different, with Beagles' isoforms being 10 times stronger inhibitors compare to those of Mini-Schnauzers'. Isoforms C + D of NC were the main isoforms isolated in stone-forming dogs. CONCLUSION: NC of these two species of dogs differently affects calcium oxalate crystallization and might have a role in determining ulterior urinary stone formation.
Documentos Relacionados
- Integrated Management of Urinary Stone Disease
- Urinary Stone Diseases: The Practical Guide to Medical and Surgical Management
- Upper urinary tract stone compositions: the role of age and gender
- Studying inhibition of calcium oxalate stone formation: an in
vitro approach for screening hydrogen sulfide and its metabolites - Editorial Comment: Upper urinary tract stone compositions: the role of age and gender