title: Proenkephalin-A mRNA is widely expressed in tissues of the human gastrointestinal tract.
abstract: BACKGROUND
  It has been shown that the non-opioid effects of Met-enkephalin, which is derived from proenkephalin-A, are mediated through a specific opioid growth factor (OGF) receptor which is assumed to be involved in the control of cell growth. The expression and tissue location of proenkephalin-A mRNA in the gastrointestinal tract remains largely unknown.
  
  
  METHODS
  In this study we have analyzed the expression of proenkephalin-A mRNA in the human esophagus, gastrointestinal tract and surrounding organs by means of reverse-transcriptase PCR (RT-PCR).
  
  
  RESULTS
  The present study demonstrates proenkephalin-A mRNA expression in the human esophagus, gastrointestinal tract, pancreas, and gallbladder.
  
  
  CONCLUSIONS
  The present study demonstrates proenkephalin-A mRNA expression in regions of the human esophagus, gastrointestinal tract, pancreas, and gallbladder tissues which provides information for the future mapping of proenkephalin-A mRNA and protein expression/co-expression at the cellular level.
authors.affiliation: Clinical Microbiology, Molecular Biology Laboratory, University Hospital Linköping, Linköping, Sweden. hanmo@ibk.liu.se
authors.forename: Hans-Jürg
authors.initials: HJ
authors.lastname: Monstein
authors.forename: Niclas
authors.initials: N
authors.lastname: Grahn
authors.forename: Bodil
authors.initials: B
authors.lastname: Ohlsson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004745:Enkephalins / Q000378:metabolism*; D005260:Female; D005704:Gallbladder / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000378:metabolism; D011498:Protein Precursors / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D004745:Enkephalins; D011498:Protein Precursors; D012333:RNA, Messenger; C029992:proenkephalin