Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of a number of peptides which are found in the gastrointestinal tract have been ascertained on the direct current recorded dorsal and ventral root responses of the isolated hemisected toad spinal cord. Motilin, substance P, bombesin, neurotensin, and thyrotropin releasing hormone had potent depolarizing actions on dorsal root terminals and motoneurons. These substances evoked discernable effects at concentrations as low as 10--7 M, or even lower with motilin. The effects of motilin, neurotensin, and thyrotropin-releasing hormone were greatly reduced or abolished by perfusion of the preparation with tetrodotoxin. Adrenocorticotrophic hormone, secretin, and pancreozymin (cholecystokinin) also depolarized dorsal root terminals and motoneurons. The effects of secretin and cholecystokinin were not abolished by tetrodotoxin. Leu- and Met-enkephalin had weak hyperpolarizing actions on the dorsal and ventral root potentials of repetitively stimulated preparations. Gastrin, gastric inhibitory peptide, glucagon, and somatostatin had no apparent effects on the responses of the preparation. Angiotensin and vasopressin both had rather weak depolarizing effects on the dorsal and ventral roots.
 ...
PMID:Actions of various gastrointestinal peptides on the isolated amphibian spinal cord. 11 60

Increased gastric acid secretion occurs after extensive intestinal resection in man, dog, rat, and monkey. Hypergastrinemia has been observed in patients with short gut syndrome and appears to accompany the hyperacidity after intestinal resection in dog, rat, and monkey. Postresectional hypergastrinemia is caused by increased release of gastrin and/or decreased degradation of the hormone. Other hormonal changes after extensive resection include increased insulin, GIP, pancreatic glucagon, and decreased enteroglucagon.
 ...
PMID:Hyperacidity and hypergastrinemia following extensive intestinal resection. 11 43

After a review on the historical development of morphological investigations of entero-endocrine cells, dating back to 1870, a detailed synoptical review of the current stage of findings in this field is given. At the present time nine different endocrine cell types can be distinguished in the epithelium of the gastrointestinal tract. Criteria for this differentiation are properties concerning specific staining methods, aldehyde-induced fluorescence, immunohistochemistry, and ultrastructure. From present results it is obvious that distinct cell types are responsible for the synthesis of defined polypeptide hormones (e.g. gastrin, secretin, enterogastrone). The metabolism of amines, in relation to the endocrine cells of the gastrointestinal tract is of particular interest here. Points investigated include the uniqueness of endocrine cells, with regard to the metabolism of biogenic amines ("APUD-cells") and the possibility of serotonin synthesis by a definite cell type, i.e. by the EC-cell ("enterochromaffin" cell). In our experimental animal, male Wistarrats, seven different entero-endocrine cell types can be discerned by ultrastructural means: EC-, ECL-, G-, AL-, EG-, D- and D1-cells. The I-cell (found in other species) can hardly be distinguished from the AL-cell by ultrastructural means and the S-cells, as found in other species, are not to be found at all. Only some of the cited cell types can be seen by fluorescence microscopy. After formaldehyde-treatment of the tissue, the "enterochromaffin" cell shows a yellow, serotonin-specific fluorescence. This cell corresponds in shape, number and distribution to the ultrastructurally defined EC-cell. EC-cells are found predominantly in the pyloric region and the duodenum and less frequently in the middle- and hindgut and the cardiac region; seldomly EC-cells are encountered in the oxyntic gland area of the stomach. In the rat gastro-intestinal tract, number and fluorescent intensity of EC-cells does not always correspond with the serotonin content of a certain region--sometimes the level of serotonin is largely determined by the mast cells, which in the rat also contain serotonin. For example, the high serotonin content of the oxyntic gland area, which contains very few EC-cells, has to be contributed nearly exclusively to mast cell serotonin. Mast cells can be domonstrated by fluorescence microscopy, due to their histamine content, after treatment of the tissue with o-phthalaldehyde (OPD). It seems likely that the histamine content, especially that of the so-called "atypical mast cells" of the mucosa, is inversely related to their respective serotonin content. --In addition to mast cells, OPD-treatment leads to a fluorescence in some of the entero-endocrine cells of the gastrointestinal epithelium. In the gastric epithelium these fluorescing cells should be regarded as histamine-containing ECL-cells and glucagon-containing AL-cells while in the colonic epithelium they are considered to be glucagon-containing AL-cells...
 ...
PMID:[The endocrine cells of the gastrointestinal epithelium and the metabolism of biogenic amines in the gastrointestinal tract (author's transl)]. 13 9

Adult rats were rendered diabetic by a single iv injection of streptozotocin (70 or 75 mg/kg). In these rats, serum insulin fell to minimal levels during the 48 h following drug treatment, and this was roughly paralleled by a progressive decrease in the ability of the lung to oxidize glucose. The addition of insulin to diabetic rat lung slices in vitro had no restorative effect on the depressed glucose oxidative rate during a 2 h incubation period; however, two daily treatments of the rats with 1 unit of protamine, zinc insulin completely restored lung glucose oxidation rate to normal, without significantly reducing the hyperglycemic state of the rats. An examination of the temporal changes in glucose utilization by the rat lung after acute insulin treatment revealed that the diabetic lung responded directly to serum levels of insulin, whereas the normal lung appeared to be unaffected by serum insulin levels as hihg as 87 ng/ml. The reduced rate of glucose oxidation in the diabetic lung was apparent after perfusion of the lung with glucose-free medium, and was characterized by a significant reduction in Vmax without an alteration in Km. This was attended by a depressed ability of the lung to incorporate [3H]leucine into protein and an increased ability to produce lactate, but hexose monophosphate shunt activity was normal. Specific receptors for insulin have been identified and partially characterized in crude membrane preparations of normal rat lung. The interaction of insulin with these receptors was rapid, reversible, saturable, and was dependent upon time and temperature. The binding of labeled insulin was inhibited by low concentrations of unlabeled insulin and by high concentrations of proinsulin, whereas it was unaffected by the presence of glucagon, gastrin, prolactin, ACTH, or growth hormone in microgram amounts. These observations suggest that insulin regulates the transport and utilization of glucose in the rat lung, and that this tissue contains specific receptors for insulin.
 ...
PMID:Pulmonary insulin responsivitiy: in vivo effects of insulin on the diabetic rat lung and specific insulin binding to lung receptors in normal rats. 14 46

A 39-year-old bus driver had been suffering for 2 years from a malignant polypoid mucosal proliferation of the upper nasal concha-ethmoid region, resembling a highly differentiated, villous-glandular adenocarcinoma of enteric type. There were numerous mono- and amphicrine cells and a massive quantity of oxyphilic, frequently Paneth-like goblet cells in the tumor. Immune-histochemically, a number of gastrin- and fewer glucagon-positive cells were identified. The somatostatin level in the serum was clearly increased. Electron-microscopically, 7 different endocrine cell types were identifiable, in order of decreasing frequency: A-like- and G-cells, both types of 5-HT-cells, A-cells, EG- and K-cell-like elements. Particularly impressive were the muco-argyrophilic amphicrine cells, containing A-granules. The unusual enteric character of the carcinoma seems to result from boundary movements and tissue displacements in an ecto-entodermal embryonic border region. There was no history of occupational wood dust inhalation.
 ...
PMID:Endocrine-amphicrine enteric carcinoma of the nasal mucosa. 15 75

Twenty-four endocrine pancreatic tumors were examined immunohistochemically for insulin, glucagon, gastrin and ACTH. In seven of these tumors, more than one peptide-hormone-containing cell type was observed. These seven tumors were also examined with conventional staining methods for the presence of A1, A2, and B cells. The results showed that these staining methods do not always distinguish between the different hormone-producing cell types of endocrine pancreatic tumors. In spite of the fact that several types of hormone-secreting cells were found in the tumors, the case histories described symptoms characteristic of hypersecretion of only one of the hormones. The hormone of the predominating cell type could not always explain the clinical symptoms. Our results indicate the endocrine pancreatic tumors often are multihormonal. Therefore, it would seem advisable to screen serum from all insuloma patients for a variety of peptide hormones.
 ...
PMID:Mixed endocrine pancreatic tumors producing several peptide hormones. 16 86

One of five gastro-entero-pancreatic hormones, gastrin, serotonin, histamine, glucagon, and insulin, was intraperitoneally administered for a long period to the rats that received N-methy-N'-nitro-N-nitrosoguanidine. A frequent development of scirrhous carcinoma was demonstrated in the group treated with gastrin.
 ...
PMID:Effect of gastro-entero-pancreatic endocrine hormones on the histogenesis of gastric cancer in rats induced by N-methyl-N'-nitro-N-nitrosoguanidine; with special reference to development of scirrhous gastric cancer. 17 Nov 95

In the presence of 5 mM theophylline, secretin and vasoactive intestinal peptide (VIP) each increased cyclic adenosine 3':5'-monophosphate (cyclic AMP) in acinar cells isolated from guinea pig pancreas. Without theophylline, neither peptide altered cellular cyclic AMP. Glucagon, which is similar to secretin and VIP both in chemical structure and spectrum of biologic activities, neither stimulated cellular cyclic AMP nor inhibited the stimulation produced by secretin or by VIP. Other agents which were tested and found not to increase cellular cyclic AMP were cholecystokinin, carboxyl-terminal octapeptide of cholecystokinin, gastrin I, gastrin II, bovine pancreatic polypeptide, carbamylcholine, and prostaglandin E1. Neither carboxyl-terminal octapeptide nor gastrin I altered the stimulation of cellular cyclic AMP produced by secretin or VIP. With natural secretin a significant increase in cellular cyclic AMP could be detected at concentrations as low as 3 x 10(-10) M and maximal stimulation occurred at 10(-8) M. VIP was approximately 1% as potent as natural secretin and maximal concentrations of secretin plus VIP increased cellular cyclic AMP to the same value as was obtained with a maximal concentration of secretin alone.
 ...
PMID:Cyclic AMP in pancreatic acinar cells: effects of gastrointestinal hormones. 17 15

In a healthy subject infusions of either secretion or glucagon caused no diarrhea. A combinations of gastrin and glucagon induced severe watery diarrhea immediately after the end of the 3 hour infusion. No diarrhea occurred from the combination of secretin and gastrin.
 ...
PMID:Hormone-induced diarrhea in man. 17 61

The parathyrin receptor in renal cortex has been investigated by studying the binding of 125I-labelled parathyrin, or of unlabelled parathyrin detected with 125I-labelled antibodies, to a partially purified plasma membrane fraction. The kinetics of hormone uptake demonstrated a biphasic response in both systems at 22 degrees C but this phenomenon was not detectable at 37 degrees C. Specific displacement of lactoperoxidase labelled 125I-labelled parathyrin occurred with 8 ng unlabelled bovine parathyrin. The apparent affinity constant was 2.3-10(8) M(-1) and the apparent binding capacity of the membranes 1.25 pmol/mg protein. Using the labelled antibody technique the receptor showed maximal binding at pH 7.0-7.5. As little as 80 pg bovine parathyrin produced a significant increase in binding of labelled anti-bovine parathyrin antibody and saturation of binding sites was demonstrated at 2.5 pmol/mg protein. Oxidized hormone showed undetectable binding. Treatment of membranes with phospholipases A or D, or Trypsin greatly reduced subsequent hormone binding. Prior incubation of membranes with 1-34 synthetic parathyrin decreased the binding of intact hormone whereas gastrin, insulin and glucagon had no effect. Growth hormone and calcitonin slightly increased parathyrin binding.
 ...
PMID:Characterization of the parathyrin receptor in renal plasma membranes by labelled hormone and labelled antibody binding techniques. 17 66


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>