Abstract： Objective With a GcneChip(R) cxpression analysis,98 known gencs and 31 exprcssed sequence tags (ESTs) were found to be differentially expressed between KK/Ta and BALB/c kidneys.To further screen the susceptibility genes for diabetic nephropathy,the temporal and spatial expression patterns of differentially expressed gene-adipsin were investigated.Methods The body weight,blood glucose,urinary albumin/creatinine ratio,and renal pathological changes of KK/Ta and BALB/c mice were measured at the 7,20,28 and 36 weeks of age.Total RNA was extracted from the kidney,heart,liver,lung,and brain.The temporal and spatial expression patterns of adipsin in diabetic KK/Ta mice were examined by competitive RT-PCR.The correlation analysis between adipsin expression and albuminuria level was carried out.Results The mRNA expression of adipsin was found in the kidney,heart,lung,and brain,but not in liver.The expression of adipsin in diabetic KK/Ta mice at 20 weeks of age was significantly down-regulated in kidney,heart,and lung than that in age-matched BALB/c mice,and unaltered in brain.Adipsin expression in KK/Ta kidneys was significantly down-regulated with aging and negatively correlated to urinary albumin/creatinine ratio( r =-0.807,P ＜ 0.05).Conclusions The expression of adipsin mRNA was downregulated in kidney,heart,and lung in diabetic state.Adipsin expression in KK/Ta kidneys was negatively correlated to urinary albumin/creatinine ratio.It might be a candidate gene for diabetic nephropathy.