ABSTRACT
Leptin, which is a plasma protein produced by the obese gene, is expressed and secreted by adipocytes. The clearance of lepdn from the circulation is unknown. But, markedly elevated serum leptin concentrations have recently been reported in patients with chronic renal failure. The purpose of the present study was to investigate plasma leptin concentration of patients with chronic renal failure and evaluate the factors affecting plasma leptin levels. Plasma leptin, insulin, and body mass index were determined in 34 patients with chronic renal failure and 55 control subjects. The plasrna leptin concentrations were not significantly different between patients with chronic renal failure and control subjects (9.4+/-11.8 vs 4.9+/-4.2ng/ml, P>0.05). The serum leptin concentrations were not significantly higher in both male and female CRF patients compared with control subjects (3.96+/-5.72 vs 2.48+/-1.65, P=0.1947, 17.07+/-14.02 vs 7.49+/-4.63ng/ml, P=0.07, respectively). And, there was no significant correlation between serum creatinine and plasma leptin. However, there was significant correlation between plasma leptin concentration and insulin level (P<0.05). We fit a multiple linear regre- ssion analysis with plasma leptin level as the dependent variable in CRF. Sex (male vs female) (P< 0.001) and insulin (P=0.004) were independently associated with plasma leptin level in CRF. These results suggested that plasma leptin level was regulated or affected by multiple factors inclu- ding sex and insulin resistance. Additional study is required to evaluate relationship between plasma leptin and insulin resistance in chronic renal failure.