An immunocytochemical study of regulatory peptides in the amphibian gastrointestinal tract

1986 ◽  
Vol 64 (1) ◽  
pp. 1-7 ◽  
Author(s):  
A. M. J. Buchan
Keyword(s):  
Gastrointestinal Tract ◽  
Substance P ◽  
Vasoactive Intestinal Polypeptide ◽  
Pancreatic Polypeptide ◽  
Endocrine Cells ◽  
Regulatory Peptides ◽  
Single Species ◽  
Gastric Inhibitory Polypeptide ◽  
Ambystoma Mexicanum ◽  
Intestinal Polypeptide

Samples from the gastrointestinal tract of two urodele and eight anuran species were investigated by immunocytochemical methods for the presence of structures immunoreactive with a range of antisera raised to the mammalian regulatory peptides. The regulatory peptides involved were gastrin, cholecystokinin, motilin, secretin, gastric inhibitory polypeptide, pancreatic glucagon, enteroglucagon, glicentin, neurotensin, somatostatin, pancreatic polypeptide, vasoactive intestinal polypeptide, substance P, Met-enkephalin, bombesin, and β-endorphin. In the majority of the species investigated, immunoreactive epithelial endocrine cells were demonstrated with the antisera to somatostatin, gastrin, enteroglucagon, and neurotensin. Motilin-containing cells were observed in a single species, Ambystoma mexicanum. Of the peptides detected within the mammalian innervation, vasoactive intestinal polypeptide, substance P, Met-enkephalin, and β-endorphin immunoreactive nerve fibres were seen. The distribution of the immunoreactive nerves differed significantly with species. Bombesin immunoreactivity was not seen within the innervation, although a population of endocrine cells was detected within the corpus of several species. No immunoreactivity was observed with the antisera to secretin, gastric inhibitory polypeptide, or pancreatic polypeptide in the species investigated.

Regulatory peptides in the amphibian pancreas

1985 ◽  
Vol 63 (9) ◽  
pp. 2121-2124 ◽  
Author(s):  
Alison M. J. Buchan
Keyword(s):  
Vasoactive Intestinal Polypeptide ◽  
Pancreatic Polypeptide ◽  
Endocrine Cells ◽  
Regulatory Peptides ◽  
Gastric Inhibitory Polypeptide ◽  
Nerve Fibres ◽  
Amphibian Species ◽  
Pancreatic Glucagon ◽  
Hyla Arborea ◽  
Intestinal Polypeptide

The pancreas from 11 amphibian species was investigated by immunocytochemical methods for the presence of immunoreactivity to a number of antisera raised to mammalian regulatory peptides. The hormones studied were insulin, pancreatic glucagon, enteroglucagon (glicentin), pancreatic polypeptide, somatostatin, gastrin, gastric inhibitory polypeptide, substance P, bombesin, methionine enkephalin, and vasoactive intestinal polypeptide. Immunoreactive cells were detected in all species with the antisera to insulin, somatostatin, pancreatic glucagon, enteroglucagon, and pancreatic polypeptide. The cells stained by the two glucagon antisera and the pancreatic polypeptide antiserum were identical in all species examined. Fine nerve fibres immunoreactive with the antiserum to vasoactive intestinal polypeptide were demonstrable only in the anuran species Hyla arborea (Hylidae). The remainder of the antisera did not detect either endocrine cells or nerve fibres in the species studied.

Tachykinin-mediated increase in motility acts independently of vasoactive intestinal polypeptide release in the canine ileum

1994 ◽  
Vol 72 (2) ◽  
pp. 109-112 ◽  
Author(s):  
E. G. Watson ◽  
J. E. T. Fox-Threlkeld ◽  
E. E. Daniel
Keyword(s):  
Gastrointestinal Tract ◽  
Substance P ◽  
Motor Activity ◽  
Vasoactive Intestinal Polypeptide ◽  
Neurokinin A ◽  
Significant Change ◽  
Dose Dependent Increase ◽  
Dose Dependent ◽  
Intestinal Polypeptide

Tachykinins induce motor activity in the canine ileum, and their mechanism of excitation may include inhibition of the release of a nonadrenergic, noncholinergic inhibitor, for which vasoactive intestinal polypeptide (VIP) is a candidate. Both substance P and neurokinin A produced a dose-dependent increase in ileal contractility with no significant change in VIP output. The highly selective NK1 agonist [Sar9, Met(O2)11]substance P and the highly selective NK2 agonist [Nle10]neurokinin A (4–10) also increased motor activity in the absence of any change in VIP released. These data suggest that the tachykinins produce motor activity in the canine ileum via a mechanism that does not involve changes in VIP output but may involve excitation through both NK1 and NK2 receptors.Key words: vasoactive intestinal polypeptide, tachykinins, gastrointestinal tract, motility.

scholarly journals On the immunocytochemical localization of the vasoactive intestinal polypeptide.

1979 ◽  
Vol 27 (5) ◽  
pp. 936-938 ◽  
Author(s):  
L I Larsson ◽  
J M Polak ◽  
R Buffa ◽  
F Sundler ◽  
E Solcia
Keyword(s):  
Gastrointestinal Tract ◽  
Vasoactive Intestinal Polypeptide ◽  
Endocrine Cells ◽  
Staining Pattern ◽  
Nerve Fibers ◽  
Immunocytochemical Localization ◽  
Exact Localization ◽  
Intestinal Polypeptide

The distribution of vasoactive intestinal polypeptide (VIP) immunoreactive nerves and endocrine cells in the gastrointestinal tract and pancreas of a number of mammalian and submammalian species has been examined in order to throw light on the exact localization of this peptide. Seven out of 8 VIP antisera demonstrated numerous nerve fibers in the gut, whereas one antiserum (TR2) revealed only scattered, few nerve fibers. The distribution of endocrine cells demonstrated by the different VIP antisera varied considerably. Thus, some antisera demonstrated only endocrine cells in the feline antrum, others only colonic endocrine cells and still others only endocrine cells of the upper gut and pancreas. The variability in staining pattern of endocrine cells as well as recent radioimmunological data makes it opportune to suggest that true VIP is a neuronal peptide and that endocrine cells store peptides resembling, but not being identical with, VIP (VIPoids).

Effects of gastric inhibitory polypeptide, vasoactive intestinal polypeptide and peptide histidine isoleucine on the secretion of hormones by isolated mouse pancreatic islets

1990 ◽  
Vol 125 (3) ◽  
pp. 375-379 ◽  
Author(s):  
C. J. Bailey ◽  
L. C. Wilkes ◽  
J. M. Conlon ◽  
P. H. Armstrong ◽  
K. D. Buchanan
Keyword(s):  
Pancreatic Islets ◽  
Insulin Release ◽  
Vasoactive Intestinal Polypeptide ◽  
Pancreatic Polypeptide ◽  
Glucose Concentration ◽  
Gastric Inhibitory Polypeptide ◽  
Glucagon Release ◽  
Islet Hormones ◽  
Mouse Pancreatic Islets ◽  
Intestinal Polypeptide

ABSTRACT The release of insulin, glucagon, somatostatin and pancreatic polypeptide (PP) by isolated mouse pancreatic islets was determined during 30-min incubations at 5.6 and 16.7 mmol glucose/l in the absence and presence of gastric inhibitory polypeptide (GIP), vasoactive intestinal polypeptide (VIP) and peptide histidine isoleucine (PHI) at concentrations of 1–1000 nmol/l. Insulin release was enhanced (>50%) by GIP (100–1000 nmol/l) and VIP (1 μmol/l) at 5.6 mmol glucose/l, but not at 16.7 mmol glucose/l. Glucagon release was increased by GIP (100–1000 nmol/l), and by VIP and PHI (1—1000 nmol/l) at both glucose concentrations in a dose-related manner (maximum increases > tenfold). Somatostatin release was similarly increased by GIP (10–1000 nmol/l) at both glucose concentrations. Only the highest concentration (1 μmol/l of PHI tested increased somatostatin release (twofold) at 5.6 mmol glucose/l, whereas PHI and VIP (1–1000 nmol/l reduced (>37%) somatostatin release at 16.7 mmol glucose/l. PP release was increased (49–58%) by 100–1000 nmol GIP/l, but was not significantly altered by VIP, and was reduced (39–56%) by PHI. The results indicate that GIP, VIP and PHI each stimulate glucagon release in a dose-related manner, but they exert discretely different effects on other islet hormones depending upon the dose and the prevailing glucose concentration. Journal of Endocrinology (1990) 125, 375–379

scholarly journals Innervation of the pancreas by substance P, enkephalin, vasoactive intestinal polypeptide and gastrin/CCK immunoractive nerves.

1979 ◽  
Vol 27 (9) ◽  
pp. 1283-1284 ◽  
Author(s):  
L I Larsson
Keyword(s):  
Blood Flow ◽  
Insulin Secretion ◽  
Substance P ◽  
Blood Vessels ◽  
Vasoactive Intestinal Polypeptide ◽  
Pancreatic Blood Flow ◽  
Major Site ◽  
Site Of Action ◽  
Immunocytochemical Studies ◽  
Intestinal Polypeptide

Immunocytochemical studies habe shown that many peptides which profoundly affect the endocrine and exocrine functions of the pancreas are localized to neurons. In the cat, such peptidergic nerves appear to innervate ganglia, islets and blood vessels of the pancreas, whereas their contributions to exocrine cells are minor. Our studies suggest that pancreatic ganglia represent one major site of action of the peptides and that, in addition, nerves containing the vasoactive intestinal polypeptide and gastrin/CCK-related peptides profoundly affect pancreatic blood flow and insulin secretion, respectively.

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