Distribution of a novel pituitary protein (7B2) in mammalian gastrointestinal tract and pancreas.
The distribution of a novel pituitary protein (7B2) was determined in the gastrointestinal tract and pancreas of four mammalian species (man, pig, guinea pig, and rat) by a specific radioimmunoassay. The highest concentrations of cross-reacting immunoreactive 7B2 (IR-7B2) were observed in the pancreas and the proximal gut (antrum or duodenum). While the intestinal concentrations varied widely among species, pancreatic IR-7B2 concentrations appeared to be similar in all four species. In the rat, pancreatic islets were found to contain high concentrations of IR-7B2 (5.73 +/- 0.14 fmol/islet, mean +/- SEM). Neonatal capsaicin treatment and enteric nerve section did not affect the concentrations of IR-7B2 in the rat intestine. Layer separation of human gut showed that IR-7B2 is mainly (71 +/- 8%) present in the epithelial fraction. Chromatographic analysis of intestinal and pancreatic extracts from the four species on Sephadex G-100 showed the presence of two immunoreactive peaks at Kav 0.3 and 0.6, but there were both inter- and intraspecies variations in the proportions of the larger and smaller molecular forms.
Suzuki
H
H
Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, U.K.
Christofides
N D
ND
Ghiglione
M
M
Ferri
G L
GL
Chretien
M
M
Seidah
N G
NG
Polak
J M
JM
Bloom
S R
SR
D000818:Animals; D000831:Animals, Newborn; D002211:Capsaicin / Q000494:pharmacology; D002850:Chromatography, Gel; D003429:Cross Reactions; D004064:Digestive System / Q000187:drug effects / Q000378:metabolism*; D006168:Guinea Pigs; D006801:Humans; D007328:Insulin / Q000276:immunology; D008297:Male; D009419:Nerve Tissue Proteins; D051859:Neuroendocrine Secretory Protein 7B2; D010179:Pancreas / Q000187:drug effects / Q000378:metabolism*; D010907:Pituitary Hormones / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D012633:Secretin / Q000276:immunology; D013045:Species Specificity; D013552:Swine
D007328:Insulin; D009419:Nerve Tissue Proteins; D051859:Neuroendocrine Secretory Protein 7B2; D010907:Pituitary Hormones; C497678:SCG5 protein, human; C497680:Scg5 protein, rat; D012633:Secretin; D002211:Capsaicin