Our results demonstrated that 1,25(OH)2D3 inhibited podocyte uPAR mRNA and protein synthesis in vitro and in vivo, which may be an unanticipated effect of 1,25(OH)2D3 and explain its antiproteinuric effect in the 5/6 nephrectomy rat FSGS model and the LPS mouse model of transient proteinuria. The gene discussed is PLAUR; the disease is focal segmental glomerulosclerosis.