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.

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.

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 Radioimmunoassay of Gastric Inhibitory Polypeptide

1978 ◽  
Vol 15 (1-6) ◽  
pp. 172-177 ◽  
Author(s):  
Linda M. Morgan ◽  
Brian A. Morris ◽  
Vincent Marks
Keyword(s):  
Vasoactive Intestinal Polypeptide ◽  
Pancreatic Polypeptide ◽  
Rabbit Antiserum ◽  
Gastric Inhibitory Polypeptide ◽  
Normal Subjects ◽  
Cross Reactivity ◽  
Plasma Samples ◽  
Mixed Meal ◽  
Overnight Fasting ◽  
The Mean

Summary A radioimmunoassay for the measurement of gastric inhibitory polypeptide (GIP) in unextracted plasma in man has been developed using a rabbit antiserum raised against porcine GIP. Porcine GIP was employed also as standard and to produce a 125I-labelled tracer. The assay was able to distinguish 110 pg/ml GIP from zero in plasma samples. Negligible cross-reactivity was demonstrated with cholecystokinin, insulin, pancreatic polypeptide, glucagon, secretin, and vasoactive intestinal polypeptide. The mean overnight fasting plasma GIP level in 28 normal subjects was 203 pg/ml (range: undetectable—420 pg/ml). Plasma GIP levels rose, within 45 minutes of eating a mixed meal, to a mean level of 1573 pg/ml.

Sign in / Sign up

Export Citation Format

Share Document