Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027497 (nausea)
 23,468 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The newly recognized class of 5-hydroxytryptamine receptors (5HT3) may be involved in the induction of nausea, since their pharmacological antagonists are effective against emesis induced by chemotherapy. 5HT3 receptors are present on enteric neurons, and 5HT3 blockers may produce mild constipation; we thus hypothesized that 5HT3 receptors would modulate colonic motility. To determine if GR 38032F, a selective 5HT3 antagonist known to have antiemetic effects, influences colonic transit in health, a randomized, double-blind, placebo-controlled crossover study was performed. Using a radiopaque marker technique, colonic transit was quantified in 39 healthy volunteers (19 men, 20 nonpregnant women) 18-70 years of age. On a standard 25-g fiber diet, 16 mg of GR 38032F was given orally thrice daily. Gastrointestinal peptides (peptide YY, human pancreatic polypeptide, neurotensin, motilin, gastrin-cholecystokinin, substance P) were also measured in plasma fasting and postprandially. Mean total colonic transit time on placebo was 27.8 hr, while on GR 38032F it was 39.1 hr (P less than 0.0005). Transit times through the left colon (P less than 0.0005) and rectosigmoid (P less than 0.05) were prolonged by the drug, but right colonic transit was not significantly altered. Transit times did not correlate with age or gender, but subjects with shorter transit times were significantly more affected than were those with longer transit times. The peak release of peptide YY was minimally decreased following GR 38032F (P less than 0.01), but the peak and integrated postprandial responses of human pancreatic polypeptide, neurotensin, motilin, gastrin-cholecystokinin, and substance P were not significantly altered by the drug.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:GR 38032F (ondansetron), a selective 5HT3 receptor antagonist, slows colonic transit in healthy man. 213 32

To determine if carbohydrates perfused into the ileum affect gastric emptying and circulating levels of gastrointestinal hormones, 18 healthy subjects were intubated with an oroileal tube. A 400-cal (60% carbohydrate, 20% protein, 20% fat) homogenized meal labeled with 111In-DTPA was then infused into the stomach over 10 min. Simultaneously, a test solution of normal saline (n = 6) or 12.5 (n = 4), 25 (n = 4), 50 (n = 2), or 100 (n = 2) mg/min of carbohydrates (75% rice starch, 25% glucose) containing a nonabsorbable marker, polyethylene glycol, was continuously perfused into the terminal ileum at 3 ml/min for 7 h. In one-half of the subjects the perfusate contained an amylase inhibitor (3.3 mg/ml) that reduced starch digestion and carbohydrate absorption. Gastric emptying was measured by a dual-headed gamma-camera. Plasma concentrations of hormones and the amount of carbohydrates passing the ileum were measured every 10 min. The amylase inhibitor significantly reduced the absorption of complex carbohydrates from the terminal ileum (p less than 0.05). Gastric emptying was significantly slowed by ileal perfusion of carbohydrates (p less than 0.01). This effect was enhanced by the amylase inhibitor (p = 0.06). Plasma concentrations of C-peptide, glucagon, motilin, gastrin, and human pancreatic polypeptide were not related to gastric emptying or ileal perfusates, but decreased concentrations of gastric inhibitory polypeptide and neurotensin and increased concentrations of peptide YY were significantly associated (p less than 0.05) with slowing of gastric emptying. Perfusing carbohydrates into the ileum was associated with nausea, abdominal pain, and vomiting, but we could detect no direct relationship between the onset of these symptoms and gastric emptying. Slowing of gastric emptying of a homogenized mixed meal by the entry of complex carbohydrates into the ileum may be partly mediated by peptide YY or nonvagally mediated neural mechanisms.
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PMID:Effect of ileal perfusion of carbohydrates and amylase inhibitor on gastrointestinal hormones and emptying. 246 4

Antagonists of 5-hydroxytryptamine type 3 (5HT3) receptors reduce the nausea induced by cisplatinum, but the effects of these agents on 5HT3 receptors in the human gut remain to be defined. We examined the actions of one of these drugs (Glaxo GR 38032F) on small intestinal transit and mouth-to-cecum transit times in healthy man. We also quantified its effects on the release of peptide YY (PYY), neurotensin, human pancreatic polypeptide, gastrin-cholecystokinin, and motilin. Ten healthy volunteers were enrolled in a randomized, double-blind, placebo-controlled crossover study. Following a single intravenous dose of GR 38032F (0.15 mg/kg), we measured the time to appearance in plasma of sulfapyridine after injection of salicylazosulfapyridine into the duodenum. This was used as a measure of duodenocecal transit. The appearance of hydrogen in breath after ingestion of a meal containing lactulose was also correspondingly used to quantify the mouth-to-cecum transit of the "head" of the meal. Gastrointestinal hormones were assayed in plasma by specific RIAs; samples were drawn fasting (10 min after injection) and after breakfast (358 calories: 15.7 g protein, 55.4 g carbohydrate, 8.1 g fat). The postprandial integrated response and peak release of PYY was decreased by GR 38032F. There was also a trend for the peak release of neurotensin to be reduced. GR 38032F did not significantly alter small intestinal transit times or mouth-to-cecum transit times. We conclude that GR 38032F does not have a major effect on small intestinal transit in health.
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PMID:Effect of selective 5HT3 antagonist (GR 38032F) on small intestinal transit and release of gastrointestinal peptides. 252 8

Enterally administered lipid modulates antropyloroduodenal motility, gut hormone release, appetite, and energy intake. We hypothesized that these effects would be dependent on both the load, and duration, of small intestinal exposure to lipid. Eleven healthy men were studied on four occasions in a double-blind, randomized, fashion. Antropyloroduodenal motility, plasma CCK and peptide YY (PYY) concentrations, and appetite perceptions were measured during intraduodenal infusion of lipid (Intralipid) at 1) 1.33 kcal/min for 50 min, 2) 4 kcal/min for 50 min, and 3) 1.33 kcal/min for 150 min, or 4) saline for 150 min. Immediately after the infusions, energy intake was quantified. Pressure wave sequences (PWSs) were suppressed, and basal pyloric pressure, isolated pyloric pressure waves (IPPWs), plasma CCK and PYY stimulated (all P < 0.05), during the first 50 min of lipid infusion, in a load-dependent fashion. The effect of the 4 kcal/min infusion was sustained so that the suppression of antral pressure waves (PWs) and PWSs and increase in PYY remained evident after cessation of the infusion (all P < 0.05). The prolonged lipid infusion (1.33 kcal/min for 150 min) suppressed antral PWs, stimulated CCK and PYY and basal pyloric pressure (all P < 0.05), and tended to stimulate IPPWs when compared with saline throughout the entire infusion period. There was no significant effect of any of the lipid infusions on appetite or energy intake, although nausea was slightly higher (P < 0.05) with the 4 kcal/min infusion. In conclusion, both the load, and duration, of small intestinal lipid influence antropyloroduodenal motility and patterns of CCK and PYY release.
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PMID:Effects of load, and duration, of duodenal lipid on antropyloroduodenal motility, plasma CCK and PYY, and energy intake in healthy men. 1621 Apr 15

Intraveneous (i.v.) PYY(3-36) infusions have been reported to reduce energy intake (EI) in humans, whereas few studies exist on effects of PYY(1-36). The aim of the present study was to examine effects of subcutaneous (sc) injections of PYY(1-36) and PYY(3-36) on appetite, ad libitum EI, plasma concentrations of PYY and free fatty acids (FFA) in obese males. Twenty-four males (BMI 27-40 kg/m(2)) were randomly assigned to two groups receiving sc injections of either PYY(1-36) or PYY(3-36) in a blinded, placebo-controlled, dose-escalating, cross-over study. Subjects were studied 5 days in succession, with escalating doses of PYY(1-36) [saline, 50, 100, 150, and 200 pmol PYY(1-36)/kg lean body mass (LBM)], or PYY(3-36) (saline, 25, 50, 75, and 100 pmol PYY(3-36)/kg LBM), respectively. PYY injections resulted in dose-dependent increases in plasma PYY levels but no effect on EI in either the PYY(1-36) or the PYY(3-36) group. However, increasing doses of PYY(3-36), but not PYY(1-36), resulted in increased ratings of satiety and decreased ratings of hunger, thirst, and prospective food consumption. Although not dose dependently, significant elevation of plasma FFA was seen after injection of PYY(3-36), but not PYY(1-36). Although sc administration of PYY was well tolerated, it remains to be determined whether high-dose PYY(3-36) is sufficient in reducing EI in long-term trials, and if so, whether the reduction in EI occurs without nausea. PYY(1-36) is unlikely to be important in regulating energy intake. The PYY(3-36) administrations caused a non-dose-dependent mobilization of FFA, likely through a direct effect.
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PMID:Effect of subcutaneous injections of PYY1-36 and PYY3-36 on appetite, ad libitum energy intake, and plasma free fatty acid concentration in obese males. 1756 12

CCK mediates the effects of nutrients on gastrointestinal motility and appetite. Intravenously administered CCK stimulates pyloric pressures, increases plasma PYY, and suppresses ghrelin, all of which may be important in the regulation of appetite and energy intake. The dose-related effects of exogenous CCK on gastrointestinal motility and gut hormone release, and the relationships between these effects and those on energy intake, are uncertain. We hypothesized that 1) intravenous CCK-8 would have dose-dependent effects on antropyloroduodenal (APD) pressures, plasma PYY and ghrelin concentrations, appetite, and energy intake and 2) the suppression of energy intake by CCK-8 would be related to the stimulation of pyloric motility. Ten healthy men (age 26 +/- 2 yr) were studied on four separate occasions in double-blind, randomized fashion. APD pressures, plasma PYY and ghrelin, and appetite were measured during 120-min intravenous infusions of 1) saline ("control") or 2) CCK-8 at 0.33 ("CCK0.33"), 3) 0.66 ("CCK0.66"), or 4) 2.0 ("CCK2.0") ng.kg(-1).min(-1). After 90 min, energy intake at a buffet meal was quantified. CCK-8 dose-dependently stimulated phasic and tonic pyloric pressures and plasma PYY concentrations (r > 0.70, P < 0.05) and reduced desire to eat and energy intake (r > -0.60, P < 0.05) without inducing nausea. There were relationships between basal pyloric pressure and isolated pyloric pressure waves (IPPW) with plasma CCK (r > 0.50, P < 0.01) and between energy intake with IPPW (r = -0.70, P < 0.05). Therefore, our study demonstrates that exogenous CCK-8 has dose-related effects on APD motility, plasma PYY, desire to eat, and energy intake and suggests that the suppression of energy intake is related to the stimulation of IPPW.
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PMID:Dose-dependent effects of cholecystokinin-8 on antropyloroduodenal motility, gastrointestinal hormones, appetite, and energy intake in healthy men. 1895 13

The history of anti-obesity drug development is far from glorious, with transient magic bullets and only a handful of agents currently licensed for clinical use. In view of recent progress in our understanding of the multiplicity of signalling pathways involved in appetite regulation, and the resultant deluge of reports on the anorectic efficacy of novel therapies, it seems timely to stress the need to differentiate treatments that suppress intake by primary means from those that only indirectly achieve this endpoint. The current article reviews the conceptual history of the behavioural satiety sequence (BSS), also known as the behavioural sequence of satiety, post-ingestive satiety, and the postprandial satiety sequence. Early research confirmed that natural satiation, produced by a caloric load on the gut, is associated with a predictable transition from feeding through grooming to resting. Although many less naturalistic manipulations are also capable of reducing food intake, very few do so without disrupting the normal structure of this feeding cycle. Thus, while CCK and d-fenfluramine reduce intake by accelerating but otherwise maintaining the integrity of the BSS, other anorectic interventions disrupt the BSS through response competition (e.g. d-amphetamine), nausea/discomfort (e.g. lithium chloride) and/or interference with taste-mediated positive feedback (e.g. quinine adulteration of the diet). A substantial literature now strongly supports the specific involvement of serotonin 5-HT(1B) and 5-HT(2C) receptor subtypes in satiety and in the anorectic effect of agents such as fenfluramine and fluoxetine. Recent BSS analyses have also identified rather selective anorectic profiles for the dual noradrenaline and 5-HT reuptake inhibitor sibutramine, the orexin-1 receptor antagonist SB-334867, and the broad spectrum opioid receptor antagonist naloxone. However, similar analyses have offered little/no support for the anorectic potential of the gut peptide PYY(3-36) while the acute anorectic efficacy of cannabinoid CB1 receptor antagonist/inverse agonists appears largely to be secondary to response competition. In contrast, studies with low-dose combinations of naloxone and CB1 receptor antagonist/inverse agonists have very recently confirmed the potential of drug polytherapies not only in appetite suppression but also in attenuating/eliminating unwanted side-effects. In sum, as BSS analysis offers a reliable means of differentiating the wheat (primary anorectics) from the chaff (secondary anorectics), it should form an integral part of early phase testing in any anti-obesity drug screening programme.
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PMID:Behavioural satiety sequence (BSS): separating wheat from chaff in the behavioural pharmacology of appetite. 2021 21