Therefore, we examined: 1) location of cytokine receptor CXCR4 in the rat bladder; 2) baseline bladder levels of SDF-1 (cognate ligand for CXCR4) and changes in response to a chemically-induced (cyclophosphamide; CYP) model of bladder inflammation; 3) CXCR4 expression changes after CYP-induced cystitis and 4) association between CXCR4 and MIF in the bladder before and after CYP-induced cystitis. The gene discussed is MIF; the disease is chronic cystitis.