Table 1.
Spontaneous Renal Calcinosis in Knockout Mice
| Main features | THP KO | OPN KO | THP/OPN KO | Npt2a KO | NHERF-1 KO |
|---|---|---|---|---|---|
| Normal protein location | Apical membrane of TAL of kidney | Ubiquitous/cytoplasmic | NA | Brush border of Renal PCT | Brush border of PCT & small intestine |
| Proposed role in nephrolithiasis | Macromolecule inhibitor | Macromolecule inhibitor | Macromolecule inhibitors | Ion channel | Scaffold protein |
| Crystal location in KO mice | Papilla | Papilla | Papilla | Nephron & papilla | Papilla |
| Intratubular/interstitial | Intratubular in young mice; interstitial in old mice | Interstitial | Interstitial | Mainly intratubular/occasionally interstitial | Interstitial |
| Chemical composition | Hydroxyapatite | Hydroxyapatite | ND | Apatite | ND |
| TEM | Compact concentric rings | ND | ND | Loose concentric rings | ND |
| Renal injury | Not visible | Not visible | Not visible | Not visible | Not visible |
| Inflammation adjacent to crystals | Not seen | Not seen | Not seen | Not seen | Not seen |
| Age-dependence | Highly dependent | ND | ND | Not systematically compared | Not systematically compared |
| Urinary supersaturation | Phosphorus, brushite | None | Phosphorus, brushite | Phosphorus, calcium | Phosphorus, calcium uric acid |
| Urinary stone formation | Bladder struvite stones in old mice | None | None | None | None |
| Mutations and stone risk in humans | ND | ND | NA | Yes | Yes |
| SNPs and stone risk in humans | Protective | Protective & predisposing | NA | Predisposing | Predisposing |
NA: not applicable
TAL: thick ascending limb of loop of Henle
PCT: proximal convoluted tubule
ND: not determined
TEM: transmission electron microscopy