Klotho, a cofactor in suppressing 1, 25 (OH) 2 D 3 formation, is a powerful regulator of
mineral metabolism. Klotho-hypomorphic mice (kl/kl) exhibit excessive plasma 1, 25 (OH) 2
D 3, Ca 2+, and phosphate concentrations, severe tissue calcification, volume depletion with
hyperaldosteronism, and early death. Calcification is paralleled by overexpression of
osteoinductive transcription factor Runx2/Cbfa1, Alpl, and senescence-associated
molecules Tgfb1, Pai-1, p21, and Glb1. Here, we show that NH 4 Cl treatment in drinking …