Distribution, quantitation, and origin of immunoreactive neuropeptide Y in the human gastrointestinal tract.
A radioimmunoassay for measurement of immunoreactive neuropeptide Y has been developed using antiserum from a rabbit (221) immunized with porcine neuropeptide Y. Antibody 221 has been characterized for both sensitivity and specificity. To determine the distribution of neuropeptide Y in the human gastrointestinal tract, fresh tissue specimens were separated by microdissection into the muscularis externa and the mucosa-submucosa. To examine the origin of neuropeptide Y in human colon, specimens of aganglionic and ganglionic colon were obtained from patients with Hirschsprung's disease. Immunoreactive neuropeptide Y in human gut was present in highest concentrations in the muscularis externa of the stomach and in lowest concentrations in the muscularis externa of the ileum and descending colon. Neuropeptide Y in the stomach was present in higher concentrations in the muscularis externa than in the mucosa-submucosa, but in the descending colon there were lower concentrations of neuropeptide Y in the muscularis externa than in the mucosa-submucosa. In Hirschsprung's disease, concentrations of neuropeptide Y were increased in aganglionic colon in both the muscularis externa and the mucosa-submucosa, compared to corresponding layers from proximal ganglionic colon. Extracts of the gastric muscularis externa and the colonic mucosa-submucosa were separated by C18 reverse-phase high-performance liquid chromatography. One major immunoreactive species was identified by radioimmunoassay which eluted in a position similar to synthetic human neuropeptide Y. These results demonstrated both regional and layer differences in concentrations of neuropeptide Y in human gut. Increased concentrations of neuropeptide Y in aganglionic colon from Hirschsprung's disease most likely result from enlargement of neuropeptide Y-containing extrinsic nerve fibers in both the mucosa-submucosa and the muscularis externa.
Koch
T R
TR
Gastroenterology Research Unit, Mayo Clinic, Rochester, MN 55905.
Roddy
D R
DR
Carney
J A
JA
Telander
R L
RL
Go
V L
VL
D000818:Animals; D000917:Antibody Formation; D000918:Antibody Specificity; D002851:Chromatography, High Pressure Liquid; D004064:Digestive System / Q000032:analysis*; D006627:Hirschsprung Disease / Q000378:metabolism; D006801:Humans; D007457:Iodine Radioisotopes; D009478:Neuropeptide Y / Q000032:analysis* / Q000276:immunology; D011817:Rabbits; D011863:Radioimmunoassay; D013048:Specimen Handling
D007457:Iodine Radioisotopes; D009478:Neuropeptide Y