Evidence for a neurotensin receptor in rat serosal mast cells.
OBJECTIVE
The ability of neurotensin (NT) at nmolar levels to stimulate exocytosis of the mast cell suggested that it could play a role in neuro-immune-endocrine interactions. The inhibition by a specific receptor antagonist of NT's mast cell stimulation suggested the presence of a specific mast cell NT receptor. We have here employed several probes to determine if a specific neurotensin receptor was present on rat serosal mast cells.


METHODS
Serosal mast cells were isolated from the peritoneal and pleural cavities of male Sprague-Dawley rats.


METHODS
Immunocytochemistry with an antibody raised against the C-terminal peptide of the neurotensin receptor was utilized. The same antibody was employed in immunoblotting following SDS gel electrophoresis of mast cell extracts. An RNA probe for ribonuclease protection assays (RPA) was prepared using the rat brain neurotensin receptor cDNA and polymerase chain reaction was carried out using primers based on the rat brain neurotensin receptor sequence.


RESULTS
Mast cells showed specific staining with the anti-neurotensin receptor antibody and this same antibody revealed a protein on SDS gels migrating as a 70 kDa species. Ribonuclease protection assays revealed the predicted protected fragment at approximately 450 bp while PCR amplification gave a major product at 843 bp.


CONCLUSIONS
These results indicate that a specific neurotensin receptor is present on the rat mast cell.
Feldberg
R S
RS
Department of Biology, Tufts University, Medford, MA 02155, USA. rfeldber@Tufts.edu
Cochrane
D E
DE
Carraway
R E
RE
Brown
E
E
Sawyer
R
R
Hartunian
M
M
Wentworth
D
D
D000818:Animals; D015153:Blotting, Western; D015151:Immunoblotting; D007150:Immunohistochemistry; D008297:Male; D008407:Mast Cells / Q000737:chemistry*; D010529:Peritoneal Cavity / Q000166:cytology; D010994:Pleura / Q000166:cytology; D016133:Polymerase Chain Reaction; D015347:RNA Probes; D012333:RNA, Messenger / Q000032:analysis; D012194:RNA-Directed DNA Polymerase; D051381:Rats; D017207:Rats, Sprague-Dawley; D018028:Receptors, Neurotensin / Q000032:analysis* / Q000235:genetics
D015347:RNA Probes; D012333:RNA, Messenger; D018028:Receptors, Neurotensin; D012194:RNA-Directed DNA Polymerase