title: Organic cation transporters in human nasal primary culture: expression and functional activity.
abstract: BACKGROUND
  The majority of drugs cross epithelial cells by either passive diffusion or via carrier-mediated drug transporters. The aim of this study was to investigate the transport characteristics, protein expression and localization of organic cation transporters in human nasal epithelium.
  
  
  RESULTS
  The expression, localization and transport characteristics of the transporters were investigated using permeation, PCR and immunohistochemistry. The uptake of 4-(4-(dimethylamino)styryl)-N-methylpyridinium iodide followed Michaelis-Menten kinetics. Its intracellular accumulation of the compound was inhibited by organic cation transporters (OCTs) and carnitine/organic cation transporter (OCTNs) inhibitors. Detected OCT1-3, OCTN1 and OCTN2 gene transcripts correlated with immunohistological staining for OCT1-3, OCTN1 and OCTN2 antibodies. Except for OCTN1, the antibodies were generally localized on the apical side of the epithelial cells.
  
  
  CONCLUSIONS
  Based on the immunohistochemical and uptake/transport studies, we conclude that the human nasal epithelium expresses OCT1-3, OCTN1 and OCTN2 transporters mainly on the apical side of the nasal cells.
authors.affiliation: Biopharmaceutics & Drug Delivery Laboratory, Dalhousie University, Halifax, Canada.
authors.forename: Di
authors.initials: D
authors.lastname: Shao
authors.forename: Emad
authors.initials: E
authors.lastname: Massoud
authors.forename: Utkarshini
authors.initials: U
authors.lastname: Anand
authors.forename: Ankit
authors.initials: A
authors.lastname: Parikh
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Cowley
authors.forename: David
authors.initials: D
authors.lastname: Clarke
authors.forename: Remigius U
authors.initials: RU
authors.lastname: Agu
mesh_terms: D015153:Blotting, Western; D002463:Cell Membrane Permeability; D016764:Cell Polarity; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007700:Kinetics; D009297:Nasal Mucosa / Q000187:drug effects / Q000378:metabolism*; D029362:Organic Anion Transporters, Sodium-Independent / Q000378:metabolism; D027701:Organic Cation Transport Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D027702:Organic Cation Transporter 1 / Q000378:metabolism; D000075102:Organic Cation Transporter 2; D061251:Primary Cell Culture; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000074058:Solute Carrier Family 22 Member 5; D027981:Symporters
chemical_list: D005456:Fluorescent Dyes; D029362:Organic Anion Transporters, Sodium-Independent; D027701:Organic Cation Transport Proteins; D027702:Organic Cation Transporter 1; D000075102:Organic Cation Transporter 2; C491013:SLC22A2 protein, human; C109807:SLC22A4 protein, human; C492020:SLC22A5 protein, human; D000074058:Solute Carrier Family 22 Member 5; D027981:Symporters; C114338:organic anion transport protein 3