Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Motilin, and Substance P, have previously been shown to be present in enterochromaffin (EC) cells in the gut mucosa. By comparing a specific immunofluorescence stain for Substance P with an immunoperoxidase reaction for motilin, applied sequentially to the same tissue section, it is possible to demonstrate that the two peptides are present in different cells. It is concluded that a) at least two different types of EC cells must exist and b) these results provide further evidence for the neuroectodermal origin of the gastrointestinal APUD cells. Studies of the degranulation pattern of EC cells could help to elucidate the role of amines in the mechanism of storage and secretion of different peptides under normal and pathological conditions.
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PMID:Differential localisation of substance P and motilin. 6 40

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.
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PMID:Actions of various gastrointestinal peptides on the isolated amphibian spinal cord. 11 60

Using an immunoreactive technique the two peptides, motilin and Substance P, have been localized at the ultrastructural level in enterochromaffin (EC) cells. Motilin occurs in cells containing a mixed population of biconcave and round secretory granules whereas Substance P is found in cells with exclusively round granules. These observations confirm the existence of at least two functionally and morphologically different types of EC cell in rabbit bile duct, both of which contain 5-hydroxytryptamine. Classification of the endocrine cells of the gut on a purely morphological basis is clearly impossible, however.
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PMID:Immunoelectron cytochemical localization of motilin and substance P in rabbit bile duct enterochromaffin (EC) cells. 31 87

The chemistry, localisation, release and effects of gastrointestinal hormones and some related peptides are surveyed. Their main presumed physiologic actions are: gastric acid and pepsin secretion are stimulated by gastrin and to a less degree by secretin. Acid secretion is inhibited by bulbo-enterogastrone and GIP. Biliary water and electrolytes are augmented by gastrin, CCK-PZ, secretin and VIP and inhibited by Substance P. Pancreatic bicarbonate and enzyme secretions are stimulated by secretin and CCK-PZ, especially in combination. Lower oesophageal and antral motility and tonus are elevated following gastrin and motilin; the gallbladder and small intestine empty following CCK. Gastrin regulates gastrointestinal, and CCK pancreatic, tissue growth. Somatostatin inhibits all gut hormones. All peptides are vasoactive within the splanchnic area, each one in a specific manner.
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PMID:Gastrointestinal hormones. 35 98

Using immunohistochemical techniques we studied duodenal biopsies from 18 patients with coeliac disease and 24 patients with normal duodenal morphology. We had access to antisera against the following gastrointestinal peptides: cholecystokinin (CCK), gastric inhibitory peptide (GIP), gastrin-17, glucagon-enteroglucagon, motilin, neurotensin, pancreatic peptide (PP), secretin, somatostatin, substance P and vasoactive intestinal peptide (VIP). The somatostatin, GIP, CCK, and glucagon cells were increased in number in coeliac disease. The number of motilin cells was slightly increased, while secretin cells were reduced. Cells storing gastrin-17, substance P, or neurotensin were rare in all patients regardless of diagnosis. No PP immunoreactive cells were found and VIP was localised to neurons only. In biopsies from patients having a mucosa with ridging of villi the number of the various endocrine cell types did not differ from that in the control group.
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PMID:Duodenal endocrine cells in adult coeliac disease. 38 55

In addition to established gastrointestinal hormones--secretin, cholecystokinin-pancreozymin (CCK-PZ), gastrin, and glucagon---some 30 polypeptides with gastrointestinal actions can be listed. New aspects of these substances include the following: Gastrin and vasoactive intestinal peptide (VIP) can be also encountered in the central nervous system and may act as transmitters. CCK-PZ-serum concentrations are found markedly elevated in patients with exocrine pancreatic insufficiency; this may provide the opportunity to establish a realtively simple screening test. Moreover, there is evidence that serum-CCK-PZ levels serve as satiety signal. Secretin secretion is said to be enhanced in hunger and then to act as a lipolytic hormone. In addition to enteroglucagon, a gastrintestinal peptide identical to pancreatic glucagon has been detected. Gastric inhibitory polypeptide (GIP) inhibits gastric secretion and motility (enterogastrone activity) and together with glucose it stimulates insulin release (incretin activity). Motilin increases lower esophageal sphincter pressure, enhances gastric pepsin secretion and slows down gastric evacuation. Serum levels of pancreatic polypeptide may be found elevated as a diagnostic index in patients with endocrine peptide tumors of the pancreas. Recently, the potential importance of local (paracrine) actions of gastrointestinal polypeptides has been amphasized. Predominantly paracrine activity is exhibited by some prototype hormones, e.g. somatostatin, substance P, bombesian, and the non-polypeptide compounds, prostaglandins.
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PMID:[New views on gastrointestinal hormones]. 85 99

Different peptides of natural origin were studied for their stimulant activity on the stomach of the anaesthetized rat. The group of the tachykinins (substance P and its analogues) showed a noticeable spasmogenic activity on the whole stomach from the fundus to the pylorus. Threshold doses ranged between 0.1 and 5 microgram/kg by i.v. route and the order of potency was: eledoisin greater than phyllomedusin greater than physalaemin greater than uperolein greater than substance P. A good correlation between the dose and the duration of the spasmogenic effect was always observed and tachyphylaxis never occurred. Experiments carried out with different kinds of inhibitors suggested that tachykinins act directly on the smooth muscle of the stomach. Taking into account also results obtained in other experimental conditions it was possible to state that the N-terminal part of the molecule of these peptides has a certain importance in determining the degree of their potency in the different tests. The peptide motilin, which does not belong to the family from a chemical point of view, was scarcely active, if at all, in modifying the motility of the rat stomach.
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PMID:Action of some natural peptides on the stomach of the anaesthetized rat. 88 54

Changes in plasma levels of vasoactive peptides during hemodialysis have mainly been attributed to changes in plasma volume and osmolality. This study investigated the effect of the extracorporeal circulation on plasma levels of vasoactive peptides, noradrenaline, and renin. Eleven stable hemodialysis patients were studied during sham dialysis for 60 min using a Cuprophan dialyzer (Alwall GFE11, Gambro AB, Lund, Sweden). With regard to vasoconstrictors, there was an increase in noradrenaline (NA) (13%, p < 0.05) and renin (PRA) (32%, p < 0.05), while arginine vasopressin and neuropeptide Y remained unaltered. Concerning vasodilators, an increase in substance P (SP) (23%, p < 0.05) and vasoactive intestinal peptide (VIP) (15%, p < 0.01) was observed, while a decrease in atrial natriuretic peptide (ANP) (17%, p < 0.05) and motilin (MOT) (24%, p < 0.01) occurred. Calcitonin gene related peptide and beta endorphin were unaltered. A decrease in blood pressure was observed, while heart rate remained unchanged. The authors conclude that the extracorporeal circulation, per se, affects plasma levels of vasoactive substances and influences vascular stability. The decrease in ANP and MOT might be due to adsorption to the dialysis membrane. The increase in some vasoconstrictors (NA, PRA) and vasodilators (SP, VIP) might be induced by the blood-artificial surface contact, or by other factors, e.g., heparin or cooling of the blood during the procedure.
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PMID:Effects of sham hemodialysis on plasma levels of vasoactive peptides in patients with uremia. 128 Oct 14

The fasting plasma levels of 10 vasoactive regulatory peptides were measured by radioimmunoassay in 23 stable patients with chronic renal failure receiving regular hemodialysis treatment (RDT) and compared with those of healthy controls. The plasma concentrations of arginine vasopressin, atrial natriuretic peptide, beta-endorphin, methionine-enkephalin, motilin, neuropeptide Y, substance P, and vasoactive intestinal peptide were increased. The plasma level of calcitonin gene-related peptide was not statistically different from that of the controls. The plasma concentration of gamma 2-melanocyte-stimulating hormone was lowered in the RDT-patients. The arterial blood pressure correlated with the plasma levels of motilin and neuropeptide Y. We conclude that patients with chronic renal failure receiving RDT have increased concentrations of 8 out of 10 measured vasoactive regulatory peptides. The elevated levels of vasoactive peptides may contribute to the adaptation of the cardiovascular system to impaired renal function.
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PMID:Plasma levels of vasoactive regulatory peptides in patients receiving regular hemodialysis treatment. 137 31

We examined the direct effect of motilin on longitudinal and circular smooth muscle cells isolated from the guinea pig small intestine. In addition, the effects of 8-(N,N-diethylamino)-octyl-3,4,5-trimethoxy-benzoate hydrochloride (TMB-8, an inhibitor of intracellular Ca(2+)-release), verapamil (a voltage-dependent Ca(2+)-channel blocker), and removal of extracellular Ca2+ were investigated to evaluate the role of intracellular Ca2+ stores and extracellular Ca2+ on the muscle contraction induced by motilin. The effects of atropine (a muscarinic receptor antagonist), spantide (a substance P receptor antagonist) and loxiglumide (a CCK-receptor antagonist) were also examined to determine whether the motilin-induced contraction was independent of those receptors. Motilin induced a contraction of the longitudinal and circular smooth muscle cells in a dose-dependent manner with the maximal effect attained after 30 seconds of incubation. The ED50 values were 0.3 nM and 0.05 nM, respectively. TMB-8 suppressed completely the motilin-induced contraction of both types of smooth muscle cells. Verapamil had only a slight suppressive effect. Removal of extracellular Ca2+ did not have any significant influence on motilin-induced contraction. The contractile response to motilin was not affected by atropine, spantide or loxiglumide. Our findings showed that:1) motilin has a direct contractile effect on both longitudinal and circular smooth muscle cells; 2) this contractile effect is not evoked via muscarinic, substance P or CCK receptors, and 3) the intracellular release of Ca2+ plays an important role in the contractile response to motilin on both types of smooth muscle cells.
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PMID:Direct contractile effect of motilin on isolated smooth muscle cells of guinea pig small intestine. 138 65


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