title: Plasma leptin is partly cleared by the kidney and is elevated in hemodialysis patients.
abstract: Leptin, the gene product of the ob gene, is important in the control of appetite in rodents and may have an important role in humans. The clearance of leptin from the circulation is unknown. As the leptin receptor is present in the kidney, we evaluated the role of the kidney in removing circulating leptin in humans. We measured leptin in aortic and renal vein plasma in 8 patients with intact renal function and 6 patients with impaired renal function who were undergoing elective cardiac catheterization. Renal blood flow was measured in all patients to calculate net mass balance across the kidney. In patients with intact renal function there is net renal uptake of 12% of circulating leptin, whereas in patients with renal insufficiency there is no renal uptake of leptin. In a separate cohort of 36 patients with end-stage renal failure on hemodialysis, peripheral leptin levels factored for body mass index was increased by > fourfold as compared to a group of healthy controls (N = 338). In addition, plasma leptin is not cleared by hemodialysis with a modified cellulose membrane. Additional studies are required to evaluate the role of leptin in mediating the anorexia of uremia.
authors.affiliation: Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA. sharma1@jeflin.tju.edu
authors.forename: K
authors.initials: K
authors.lastname: Sharma
authors.forename: R V
authors.initials: RV
authors.lastname: Considine
authors.forename: B
authors.initials: B
authors.lastname: Michael
authors.forename: S R
authors.initials: SR
authors.lastname: Dunn
authors.forename: L S
authors.initials: LS
authors.lastname: Weisberg
authors.forename: B R
authors.initials: BR
authors.lastname: Kurnik
authors.forename: P B
authors.initials: PB
authors.lastname: Kurnik
authors.forename: J
authors.initials: J
authors.lastname: O'Connor
authors.forename: M
authors.initials: M
authors.lastname: Sinha
authors.forename: J F
authors.initials: JF
authors.lastname: Caro
mesh_terms: D000368:Aged; D001011:Aorta; D001769:Blood / Q000378:metabolism*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007668:Kidney / Q000378:metabolism* / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy; D020738:Leptin; D008297:Male; D008875:Middle Aged; D011506:Proteins / Q000378:metabolism*; D012079:Renal Circulation; D006435:Renal Dialysis; D012082:Renal Veins
chemical_list: D020738:Leptin; D011506:Proteins