title: Effects of Leptin on Na+/Ca2+ Exchanger in PC12 Cells.
abstract: OBJECTIVE
  Alzheimer's disease (AD) is known to be related to alterations in neuronal intracellular calcium activity ([Ca2+]i). The present study revealed the distinct role of leptin in Na+/Ca2+-exchanger activity.
  
  
  METHODS
  [Ca2+]i was determined utilizing Fura-2 fluorescence. The activity of NCX was measured by removal of extracellular Na+ in the presence of external Ca2+. Na+/Ca2+-exchanger activity was further quantified from whole cell currents following removal of extracellular Na+. Na+/Ca2+-exchanger isoform NCX1 transcript levels and protein abundance were quantified by RT-PCR and Western blotting, respectively.
  
  
  RESULTS
  Exposure of PC12 cells to 30 µM amyloid (Aβ42) increased [Ca2+]i, an effect significantly blunted by 6 hours incubation with leptin before Aβ42 treatment. Moreover, leptin treatment significantly increased Na+/Ca2+-exchanger mediated Ca+ transport and current, NCX1 transcript level as well as NCX1 membrane protein abundance.
  
  
  CONCLUSIONS
  We show that leptin blunts Aβ42-evoked [Ca2+]i increase by increasing expression and activity of Na+/Ca2+-exchanger NCX1.
authors.affiliation: Experimental teaching center, Basic Medical College of Henan University of Chinese Medicine, Zhengzhou, China.
authors.forename: Zijuan
authors.initials: Z
authors.lastname: Zhang
authors.forename: Shuguang
authors.initials: S
authors.lastname: Sun
authors.forename: Caixia
authors.initials: C
authors.lastname: Du
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Juan
authors.initials: J
authors.lastname: Zhang
authors.forename: Yanqin
authors.initials: Y
authors.lastname: Zhu
authors.forename: Peilin
authors.initials: P
authors.lastname: Liu
authors.forename: Ying
authors.initials: Y
authors.lastname: Xing
mesh_terms: D016229:Amyloid beta-Peptides / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D015640:Ion Channel Gating / Q000187:drug effects; D053614:Janus Kinase 2 / Q000037:antagonists & inhibitors / Q000378:metabolism; D020738:Leptin / Q000494:pharmacology*; D008954:Models, Biological; D016716:PC12 Cells; D010446:Peptide Fragments / Q000494:pharmacology; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects; D019831:Sodium-Calcium Exchanger / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D016229:Amyloid beta-Peptides; D020738:Leptin; D010446:Peptide Fragments; D047428:Protein Kinase Inhibitors; D019831:Sodium-Calcium Exchanger; C075222:amyloid beta-protein (1-42); C110374:sodium-calcium exchanger 1; D053614:Janus Kinase 2; D002118:Calcium