Figure 1. Chronic kidney disease-associated mineral and bone disorder (CKD-MBD). Complex interactions between phosphate, FGF23, FGF receptor-1c (FGFR1c), Klotho, 1,25diOH vitamin D (calcitriol), renal 1 alpha 25OH vitamin D hydroxylase (1 alpha hydroxylase), vitamin D receptor (VDR), calcium, Ca-sensing receptor (CaSR), and parathyroid hormone (PTH).