title: HMC-1 human mast cells synthesize neurotensin (NT) precursor, secrete bioactive NT-like peptide(s) and express NT receptor NTS1.
abstract: OBJECTIVE
  To determine if mast cells synthesize the inflammatory peptide, neurotensin (NT), secrete immunoreactive and bioactive NT, and express the NT receptor NTS1.
  
  
  METHODS
  HMC-1 cells, pleural mast cells from Sprague-Dawley rats, LAD2 mast cells, and human cord blood mast cells were used.
  
  
  METHODS
  HMC-1 cells were stimulated with NT, C48/80, mastoparan, or PGE(2). For changes in cutaneous vascular permeability, anesthetized rats were injected intravenously with Evans Blue dye and intradermally with saline, NT, histamine, diphenhydramine, and C48/80.
  
  
  METHODS
  RT-PCR was used to identify RNA transcripts. Histamine was measured by fluorometric assay. In vivo cutaneous vascular permeability assays, radio-immunoassays for NT, Western blotting for the NT precursor protein and NTS1 protein from HMC-1 cells and tissues from rats were used. Immunohistochemistry was used to identify NT precursor-like proteins in HMC-1 mast cells.
  
  
  RESULTS
  HMC-1 cells express mRNAs for NT precursor, PC5A processing enzyme and NTS1 receptor. Human cord blood mast cells and LAD2 mast cells express mRNA transcripts for NT precursor and NTS1. Western blotting showed NT precursor and NTS1 receptor in HMC1. Rat tissues with high numbers of mast cells contained NT precursor proteins. NT-like peptides from HMC-1 displayed NT-like bioactivity.
  
  
  CONCLUSIONS
  HMC-1 mast cells synthesize and secrete immunoreactive and bioactive NT-like peptide(s) and express the NT receptor, suggesting that NT from mast cells might serve autocrine and paracrine roles.
authors.affiliation: Department of Biology, Tufts University, Medford, MA 02155, USA. david.cochrane@tufts.edu
authors.forename: David E
authors.initials: DE
authors.lastname: Cochrane
authors.forename: Robert E
authors.initials: RE
authors.lastname: Carraway
authors.forename: Kimberly
authors.initials: K
authors.lastname: Harrington
authors.forename: Melissa
authors.initials: M
authors.lastname: Laudano
authors.forename: Stephen
authors.initials: S
authors.lastname: Rawlings
authors.forename: Ross S
authors.initials: RS
authors.lastname: Feldberg
mesh_terms: D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003106:Colon / Q000276:immunology; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology; D006632:Histamine / Q000276:immunology; D006801:Humans; D007082:Ileum / Q000276:immunology; D008297:Male; D008407:Mast Cells / Q000276:immunology*; D009496:Neurotensin / Q000235:genetics / Q000276:immunology*; D010455:Peptides / Q000276:immunology*; D045702:Proprotein Convertase 5 / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D018028:Receptors, Neurotensin / Q000235:genetics / Q000276:immunology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012867:Skin / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology
chemical_list: D010455:Peptides; D012333:RNA, Messenger; D018028:Receptors, Neurotensin; C114036:neurotensin type 1 receptor; D009496:Neurotensin; D006632:Histamine; D045702:Proprotein Convertase 5