Effect of Calcitriol Administration on Urinary Excretion of Nephrocalcin, A Calcium-Oxalate Crystal-Growth Inhibitor
Nephrocalcin (NC) is an acidic glycoprotein that contains several residues of gamma-carboxyglutamie acid (Gla), and that inhibits the growth of calcium oxalate (CaOx) monohydrate crystals in vivo (1). Nephrocalcin has been purified from human urine (2), rat kidneys and urine (3), and from culture supernatants of both human and mouse kidney-tissue culture (4, 5). Nephrocalcin isolated from the urine of stone formers has several molecular abnormalities, including an absence of Gla residues and a decreased affinity for crystal surfaces (6). Nephrocalcin may play a role in inhibition of CaOx crystal growth in vivo, thereby preventing formation of kidney stones.
KeywordsCalcium Oxalate Proximal Tubule Cell Urinary Calcium Excretion Calcium Oxalate Monohydrate Monohydrate Crystal
Unable to display preview. Download preview PDF.
- 1.EM Worcester, Y Nakagawa, and FL Coe, Glycoprotein calcium oxalate crystal growth inhibitor in urine, Mineral Electrolyte Metab. 13: 267 (1987).Google Scholar
- 5.Y Nakagawa, D Sirivongs, WK Vishny, and FL Coe, Evidence that cultured mouse proximal tubule cells produce nephrocalcin, a calcium oxalate crystal growth inhibitor of renal origin, Kidney Int. 31: 176 (1987).Google Scholar
- 7.S Kumar, WA Franklin, E Worcester, and FL Coe, Immunohistochemical localization of nephrocalcin to proximal tubule of human kidney, submitted for publication (1988).Google Scholar
- 11.E Worcester, C Wabner, Y Nakagawa, and FL Coe, Measurement of nephrocalcin, a urinary glycoprotein crystallization inhibitor, by ELISA in normal urine: correlation with calcium oxalate crystal growth inhibition, Kidney Int. 31: 361 (1987).Google Scholar
- 12.C Wabner, D Sirivongs, P Maikrantz, Y Nakagawa, and F Coe, Evidence for increased excretion in pregnancy of nephrocalcin, a urinary inhibitor of calcium oxalate crystal growth, Kidney Int. 31: 359 (1987).Google Scholar