Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The neuropeptide Y (NPY) receptor was solubilized from rat brain membranes with the zwitterionic detergent 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate (CHAPS). The binding of 125I-NPY to CHAPS extracts was protein, time, and temperature dependent. Unlabeled NPY and the related peptides peptide YY (PYY) and pancreatic polypeptide inhibited 125I-NPY binding to solubilized receptors with relative potencies similar to those seen with membrane-bound receptors: NPY greater than PYY much greater than pancreatic polypeptide. Scatchard analysis of equilibrium binding data showed the CHAPS extracts to contain a single population of binding sites with a KD of 3.6 +/- 0.4 nM (mean +/- SEM) and a Bmax of 5.0 +/- 0.2 pmol/mg of protein. In addition the 125I-NPY binding to the soluble receptor was not inhibited by guanosine-5'-O-(3-thiotriphosphate), in contrast to the GTP sensitivity displayed by the membrane-bound receptor. Gel filtration chromatography using Sepharose 6B revealed a single peak of binding activity corresponding to a Mr of approximately 67,000, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis after chemical cross-linking revealed a single band at Mr 62,000. After solubilization and gel chromatography a 50- to 100-fold purification of the NPY receptor was obtained.
 ...
PMID:Solubilization of the neuropeptide Y receptor from rat brain membranes. 184 54

To investigate whether peptide YY (PYY) has a role in minimising fluid loss during diarrhoea, its effect on hypersecretion induced by vasoactive intestinal peptide (VIP) was studied in seven subjects with ileostomies. An isotonic electrolyte solution containing polyethylene glycol 4000 was infused directly into the duodenum and the effluent was collected for 40 min (baseline), then VIP was infused intravenously at 5 pmol.kg-1.min-1 for 500 min. PYY was infused intravenously at low doses (0.4 and 0.2 pmol.kg-1.min-1) for 100 min each during the continuous VIP infusion. Small-intestinal secretion was assessed by effluent weight and by polyethylene glycol dilution, which gave similar results. Plateau ileal output was 501 (SEM 33) ml/h during VIP infusion. PYY caused significant falls in secretion--to 404 (48) ml/h for the lower dose and to 323 (75) ml/h for the higher. It also prolonged small-bowel transit. These findings suggest that PYY is a natural inhibitor of diarrhoea and that its therapeutic potential merits investigation.
 ...
PMID:Preliminary report: role of peptide YY in defence against diarrhoea. 197 88

Mouth-caecum transit time (M-CTT) of a lactulose labelled liquid test meal has been measured in 27 coeliac patients and 10 healthy controls using the breath hydrogen technique. Although all patients were urged to maintain a gluten free diet, not all did, and there was, therefore, a wide range in the severity of fat malabsorption within the patient group. Gastric emptying of a 113Indium DTPA-labelled liquid test meal was also assessed in separate studies on six healthy controls and 11 of the coeliac patients. Fasting breath hydrogen concentrations and the response to lactulose, as assessed both by the rate of rise, and the peak breath hydrogen concentration reached, showed no difference between coeliacs and controls, regardless of the presence or absence of steatorrhoea. Mouth-caecum transit time in the 16 coeliac patients with steatorrhea (faecal fat greater than 7 g/24 h) was, however, significantly prolonged being 158 +/- 18 minutes (mean +/- SEM), compared with 70 +/- 9 minutes for the controls (p less than 0.02), and 83 +/- 15 minutes for the 11 coeliacs without steatorrhoea (p less than 0.002). Mouth-caecum transit time in the coeliac patients was linearly related to the 24 hour faecal fat excretion, r = 0.55, n = 27, p less than 0.01. Slow mouth-caecum transit in the coeliacs with steatorrhoea was not caused by delayed gastric emptying as the t1/2 for coeliacs with steatorrhoea was within the normal range. Coeliacs with delayed mouth-caecum transit had impaired insulin release but the postprandial profiles of the other peptides measured (cholecystokinin, GIP, secretin, motilin, neurotensin, enteroglucagon, and peptide YY) were all within the normal range in this group of partially treated coeliac patients.
 ...
PMID:Delayed mouth-caecum transit of a lactulose labelled liquid test meal in patients with steatorrhoea caused by partially treated coeliac disease. 367 57

The effect of peptide YY (PYY) on gastric and pancreatico-biliary secretion was studied in humans. Peptide YY was infused into groups of 6 healthy volunteers at doses of 0.59, 0.20, and 0.064 pmol X kg-1 X min-1. The two higher doses caused a significant suppression of gastric acid and pepsin output during background stimulation with pentagastrin. The middle dose of PYY (0.20 pmol X kg-1 X min-1) that increased plasma PYY levels by 27 +/- 2 pM caused a 90% +/- 18% (mean +/- SEM; p less than 0.001) reduction in the incremental gastric volume response to pentagastrin. Similarly this dose of PYY caused a substantial inhibition of the acid (77% +/- 14%; p less than 0.005) and pepsin (96% +/- 22%; p less than 0.01) response to pentagastrin; in 2 subjects, pepsin output fell to below basal levels. In contrast, the highest dose of PYY (0.62 pmol X kg-1 X min-1) had no significant influence on duodenal juice volume, output of bicarbonate, trypsin, or bilirubin during low dose stimulation with secretin (0.25 pmol X kg-1 X min-1) and cholecystokinin-8 (0.15 pmol X kg-1 X min-1). Thus PYY concentrations in the circulation similar to those seen after the ingestion of food cause a marked reduction in gastric secretion. This peptide should therefore be considered as one of the possible candidates for the classical enterogastrone.
 ...
PMID:Effect of peptide YY on gastric, pancreatic, and biliary function in humans. 383 79

Exogenous peptide YY (PYY) decreases pancreatic exocrine secretion, pancreatic endocrine function, and pancreatic blood flow. We hypothesized that pancreatic cancer cell growth may be inhibited by PYY and a new synthetic analog, BIM-43004-1. Two human pancreatic ductal adenocarcinomas, PANC-1 and Mia PaCa-2, were examined in tissue cultures. Viable pancreatic cancer cells were counted with trypan blue on a hemocytometer slide. Cells (10K, 20K, 40K, and 80K) were cultured and allowed to grow for 36 hr (n = 14/cell concentration). Pancreatic cancer cells received either PYY or BIM-43004-1 at various concentrations. Control tissue cultures received an equivalent volume of saline inoculation. After incubation with the above peptides for 24 hr, MTT tetrazolium bromide was added to assay mitochondrial activity of pancreatic cancer cells in response to PYY and its analog. MTT assay reveals a significant decrease in pancreatic cancer cell growth when PYY and BIM-43004-1 are added to the cell culture. Results in Mia PaCa-2 reveal a 24% cell growth reduction after exposure to PYY and a 23% reduction in cell growth when treated with BIM-43004-1. In PANC-1 cells, a 25% reduction in growth of cells is noted after PYY treatment and a 24% reduction in growth after BIM-43004-1 treatment. (means +/- SEM, P < 0.05 by Student's t test). Our results reveal a significant reduction in human ductal pancreatic cancer growth when treated with either PYY or its analog, BIM-43004-1. These agents may be useful hormonal adjuncts in the chemotherapy of pancreatic adenocarcinoma.
 ...
PMID:Human pancreatic cancer growth is inhibited by peptide YY and BIM-43004-1. 779 50

Reperfusion of ischaemic intestine is characterised by an initial hyperaemia with ensuing mucosal repair. This study investigated possible roles for gut vasoactive neuropeptides and trophic peptides in these phenomena. Groups of rats were monitored during superior mesenteric artery occlusion for five or 20 minutes, with or without subsequent reperfusion for five minutes. Peptide concentrations (fmol/ml) in arterial blood, were measured using specific radioimmunoassays. Intestinal ischaemia alone did not cause haemodynamic disturbance or peptide release. Reperfusion, after five minutes of ischaemia, resulted in arterial hypotension and a rise in plasma vasoactive intestinal polypeptide (mean (SEM)) (37 (3), control 11 (4), p < 0.001). After 20 minutes of ischaemia, reperfusion resulted in greater hypotension (p < 0.05) and release of both vasoactive intestinal polypeptide (31 (3), p < 0.05 v control) and the more potent vasodilator beta-calcitonin gene related peptide (49 (3), control 23 (1), p < 0.001). By contrast, the vasodilators alpha-calcitonin gene related peptide and substance P and the vasoconstrictors neuropeptide Y, peptide YY, and somatostatin were not released. Bombesin, a stimulatory neuropeptide, was released after 20 minutes of ischaemia/reperfusion (13 (2), control 7 (3), p < 0.05). Plasma enteroglucagon rose from control (51 (4)) to 110 (16) (p < 0.001) and to 158 (27) (p < 0.005) after five and 20 minutes of ischaemia/reperfusion. The potent enteric vasodilators vasoactive intestinal polypeptide and beta-calcitonin gene related peptide, unopposed by vasoconstrictors, may promote post-ischaemic intestinal hyperaemia. The rise in plasma enteroglucagon may point to diffuse mucosal injury and is consistent with the putative trophic role of this peptide.
 ...
PMID:Release of vasodilator, but not vasoconstrictor, neuropeptides and of enteroglucagon by intestinal ischaemia/reperfusion in the rat. 782 5

Reconstructing the enteric tract after near-total proctocolectomy by interposing a jejunal pouch between the distal ileum and the distal rectum slows small intestinal transit and decreases the number of stools per day compared to a conventional ileal pouch-distal rectal reconstruction. Our hypothesis was that the jejunal pouch operation brings about these results by protecting the ability of the ileal mucosa to secrete peptide YY, thus augmenting the hormonal ileal brake on small intestinal transit and decreasing the stool frequency. In five jejunal pouch dogs and five ileal pouch dogs, more than 6 months after the operation, serum peptide YY concentrations were determined before and at 30-minute intervals for 180 minutes after a standard meal. Fasting serum concentrations of peptide YY, measured by radioimmunoassay, were greater in jejunal pouch dogs (mean +/- SEM, 1340 +/- 143 pg/ml) than in ileal pouch dogs (804 +/- 52 pg/ml; P < 0.01). Postprandial peptide YY concentrations in jejunal pouch dogs were also greater at 30 minutes (jejunal pouch = 1524 +/- 131 pg/ml, ileal pouch = 913 +/- 67 pg/ml; P = 0.01) and 60 minutes after the meal (jejunal pouch = 1723 +/- 250 pg/ml, ileal pouch = 1001 +/- 70 pg/ml; P = 0.05) and peaked sooner (jejunal pouch = 81 +/- 17 minutes, ileal pouch = 147 +/- 12 minutes; P = 0.01). We concluded that the jejunal pouch operation results in greater ileal fasting and postprandial secretion of peptide YY than the ileal pouch operation. The greater release may account, in part, for the slower small bowel transit and decreased number of stools after the jejunal pouch operation.
 ...
PMID:Enhancing release of peptide YY after near-total proctocolectomy: jejunal pouch vs. ileal pouch-distal rectal anastomosis. 1130 55

The peptides of the neuropeptide Y (NPY) family exert their functions, including regulation of appetite and circadian rhythm, by binding to G-protein coupled receptors. Mammals have five subtypes, named Y1, Y2, Y4, Y5 and Y6, and recently Y7 has been discovered in fish and amphibians. In chicken we have previously characterized the first four subtypes and here we describe Y6 and Y7. The genes for Y6 and Y7 are located 1 megabase apart on chromosome 13, which displays conserved synteny with human chromosome 5 that harbours the Y6 gene. The porcine PYY radioligand bound the chicken Y6 receptor with a K(d) of 0.80 +/- 0.36 nm. No functional coupling was demonstrated. The Y6 mRNA is expressed in hypothalamus, gastrointestinal tract and adipose tissue. Porcine PYY bound chicken Y7 with a K(d) of 0.14 +/- 0.01 nm (mean +/- SEM), whereas chicken PYY surprisingly had a much lower affinity, with a Ki of 41 nm, perhaps as a result of its additional amino acid at the N terminus. Truncated peptide fragments had greatly reduced affinity for Y7, in agreement with its closest relative, Y2, in chicken and fish, but in contrast to Y2 in mammals. This suggests that in mammals Y2 has only recently acquired the ability to bind truncated PYY. Chicken Y7 has a much more restricted tissue distribution than other subtypes and was only detected in adrenal gland. Y7 seems to have been lost in mammals. The physiological roles of Y6 and Y7 remain to be identified, but our phylogenetic and chromosomal analyses support the ancient origin of these Y receptor genes by chromosome duplications in an early (pregnathostome) vertebrate ancestor.
 ...
PMID:Neuropeptide Y-family receptors Y6 and Y7 in chicken. Cloning, pharmacological characterization, tissue distribution and conserved synteny with human chromosome region. 1664 May 67

Weight gain and risk of type 2 diabetes are inversely associated with a high intake of insoluble cereal fibres. Because nutrient-induced changes of 'satiety hormones' from the gut may play a role in this process, we evaluated the effects of purified insoluble fibres on postprandial responses of plasma peptide YY (PYY), serum ghrelin and satiety as secondary outcome measures of a study investigating effects of cereal fibres on parameters of glucose metabolism. Fourteen healthy women were studied on six occasions in a randomized, single-blind, controlled crossover design. After 24 h run-in periods and 10 h overnight fasts, subjects ingested isoenergetic and macronutrient matched portions of control white bread or fibre-enriched bread (wheat-fibre or oat-fibre) at 08.15 hours. Gut hormones and hunger scores were measured for 300 min. Basal PYY and ghrelin concentrations were not different between the test meals (P>0.15). Postprandial responses of PYY and ghrelin were blunted after the intake of wheat-fibre (total area under the curve (AUC) PYY, 177.9 (SEM 8.1) (pmol/l) min; P=0.016; ghrelin 51.0 (SEM 2.5) (pmol/l) min; P=0.003), but not after oat-fibre (PYY 226.7 (SEM 25.7) (pmol/l) min; P>0.15; ghrelin 46.2 (SEM 1.6) (pmol/l) min; P=0.127), compared to control (PYY 247.5 (SEM 25.6) (pmol/l) min; ghrelin 42.5 (SEM 1.3) (pmol/l) min). Postprandial hunger scores were unaffected by the different test meals (P>0.15). Thus, oat- and wheat-fibre consumption result in different postprandial responses of PYY and ghrelin, but interestingly do not differ in satiety effects.
 ...
PMID:Wheat-fibre-induced changes of postprandial peptide YY and ghrelin responses are not associated with acute alterations of satiety. 1709 65

Fasting and postprandial levels of human peptide YY (PYY) were recently found to be lower in obesity. To investigate whether PYY levels are correspondingly high in patients with anorexia nervosa, PYY concentrations were analyzed under basal conditions and in response to a liquid meal. We investigated PYY plasma levels in 16 female anorectic (BMI 15.2+/-0.3 kg/m2) and seven lean subjects (BMI 21.3+/-0.6 kg/m2) before and after ingestion of a liquid meal (250 kcal; 15% protein, 55% carbohydrates, and 30% fat). PYY levels were analyzed using PYY ELISA (DSL, USA). Values are given as mean+/-SEM. Basal PYY levels in anorectic patients (89.0+/-14.4 pg/mL) were not significantly different from lean subjects (64.1+/-12.1 pg/mL). Postprandial PYY levels in healthy volunteers increased significantly after 20 and 60 min (80.4+/-12.7 and 96.0+/-19.9 pg/mL, respectively). In anorectic women PYY was increased at 20 min (137.9+/-19.5 pg/mL) and at 60 min (151.3+/-19.2 pg/mL). No difference was found between both groups. We conclude that basal and postprandial PYY levels in normal weight women are not different from anorectic patients. We could not confirm the recently published blunted postprandial PYY response in anorexia, a finding that merits further study.
 ...
PMID:Peptide YY release in anorectic patients after liquid meal. 1715 59


1 2 Next >>