Abstract: Objective To elucidate the relationship between the expression leptin of receptors mRNA the surface of peripheral blood mononuclear cells and the plasma levels of leptin and tumor nocrosis factor a (TNF-a), and the cause of high plasma levels of proinflammatory cytokines in patients with end-stage renal disease(ESRD). Methods Human peripheral blood mononuclear cells were isolated from 20 ESRD patients(12 of them underwent hemodialysis and 8 of them did not) and 10 healthy controls. The levels of plasma leptin and TNF- a were measured. The relative expression levels of the 2 major leptin receptor splice variants, the long form (Ob-Rb) and the short form (Ob-Ra) in peripheral blood mononuclear cells，were measured by semi-quantitative reverse transcript polymerase chain reaction (RT-PCR).Results Plasma leptin and TNF-a levels were much higher in ESRD group than those in control group. However there was no significant difference between hemodialysis sub-group and non-dialysis sub-group. Plasma leptin levels were significantly correlated with BMI and FAT% in all subjects and with plasma TNF-a levels only in hemodialysis sub-group （r=0.688，P＜0.05）and non-dialysis sub-group (r=0.801，P＜0.001).But there was no,correlation in normal control group. Both Ob-Ra and Ob-Rb were coexpressed in all mRNAs tested. However, the expression level of the short form (Ob-Ra) was 7-fold higher on average than that level of the long form (Ob-Rb)(P＜0.001). The predominance of the short splice variant over the long one was apparent in all samples. The relative expression levels of Ob-Rb mRNA and Ob-Ra mRNA in ESRD were respectively higher than those in control group(P＜0.001, P＜0.001). Plasma leptin and TNF-a levels were significantly correlated with the relative expression levels of Ob-Ra mRNA and Ob-Rb mRNA in hemodialysis sub-group and non-dialysis sub-group.Conclusion Both Ob-Ra and Ob-Rb were coexpressed on the surface of peripheral blood mononuclear cells in ESRD patients. Short form receptor of leptin (Ob-Ra is predominent in all samples. Their relative expression levels are higher than those in healthy controls.The relationaship between hyperleptinemia and proinflammatory cytokines is to be investigated.

Key words: Peripheral blood mononuclear cells, Obese receptor, TNF-a