Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020175 (hunger)
 5,670 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

Cholecystokinin octapeptide (CCK-8) or saline was intravenously infused for 5 min before and 5 min during a meal of macaroni and beef, served 20 min after a preload of either 100 or 500 g of soup to 12 nonobese men. Intake of the test meal was significantly lower when CCK-8 was given, following the larger preload, than after any of the other treatments. There were no significant differences among the other three treatment conditions. These results are consistent with the hypothesis that gastric, but not merely pregastric, stimulation interacts with CCK-8 to reduce food intake in humans. Although gastric filling seems to be the most likely stimulus for the interactive effect with CCK-8, other factors such as activation of nutrient-sensitive sites cannot be eliminated. In addition, hunger ratings were significantly lower immediately after the larger soup preloads than after the smaller. Hunger ratings after the soup also correlated better with test-meal intake after the large soup preloads with and without CCK-8 than after the smaller preloads. Hunger did not correlate significantly with test meal intake after the small soup preload with CCK-8. These results suggest that hunger ratings are more sensitive predictors of intake when the stomach is relatively full (i.e., after a large preload) than when it is relatively empty (i.e., after a small preload) at the time the hunger rating is taken.
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PMID:Effect of a soup preload on reduction of food intake by cholecystokinin in humans. 201 39

The putative satiety peptide cholecystokinin octapeptide (CCK-8) has been shown to reduce ethanol intake induced by prior fluid deprivation. Since fluid-deprived animals tend to reduce their food intake and consequently become hungry, the ability of CCK-8 to reduce ethanol intake might be limited to conditions where the motivation for food and fluid are accentuated. The present study assessed this possibility by examining the effect of peripheral injections of CCK-8 on voluntary ethanol intake fostered by the limited access procedure which uses food- and water-sated rats. Under these conditions CCK-8 still produced a dose-dependent decrease in ethanol intake. These results demonstrate that CCK-8 reduces ethanol intake even in the absence of hunger and thirst drives.
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PMID:Cholecystokinin octapeptide reduces ethanol intake in food- and water-sated rats. 232 Jun 63

Of the many factors that influence food intake, there is strong evidence that opioid and CCK peptides, which stimulate feeding and elicit satiety, respectively, are important components that may act in concert to regulate energy balance. Cholecystokinin peptides have been isolated in both the brain and gastrointestinal tract, and changes in concentration in the brain and in plasma have been shown to vary with feeding. Peripherally injected CCK has been shown to elicit satiety in many species, including humans, an effect that may be mediated in the CNS via the vagus. In several species, most notably the sheep, direct injection into the CSF potently decreases food intake. Questions remaining regarding the role of CCK peptides in eliciting satiety include the sites and mechanisms of action. It is unknown whether CCK acts directly on receptors, indirectly on some other parameter, or as a neurotransmitter. Although opioid peptides have also been localized in portions of both the periphery and brain, a specific physiological role for their presence has not yet been determined. Opioid peptides from three families--endorphins, enkephalins, and dynorphins--have been shown to stimulate feeding in various species. They have been active at several opioid receptor types in the CNS, but there is limited evidence to suggest they affect food intake when administered peripherally. In contrast, peripheral injection of opiate antagonists has effectively decreased food intake, an observation that led to the original hypothesis that opioids were involved in the hunger component in the control of food intake and that excess concentrations might be involved in the development of obesity. An increasing body of evidence supports the concept that opioid and CCK peptides may interact to control food intake, but the evidence is more suggestive than conclusive.
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PMID:Role of cholecystokinin and opioid peptides in control of food intake. 286 68

There is still much to learn of the sites and mechanisms of action of brain CCK peptides and their interaction with other brain peptides and neurotransmitters. The findings obtained from studies in sheep and other species provide evidence for brain CCK peptides functioning as important transmitters of hunger and satiety signals. We have hypothesized that signals, either neural or humoral, peripherally generated as a result of feeding induce secretion of CCK from specific (paraventricular) brain sites into the CSF (FIG. 1). Specialized ependymal cells, such as tanycytes, may take up CCK from the CSF for transport to receptor sites which mediate CCK's specific functions (such as changes in rumen motility, suppression of insulin secretion, and behavioral satiety). Evidence also exists to indicate the involvement of specific hypothalamic sites in either the release or the action of CCK.
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PMID:Central nervous system cholecystokinin and the control of feeding. 299 48

Ceruletide is a synthetic decapeptide closely resembling the 8-carboxy-terminal peptide of cholecystokinin (CCK-8) with which it shares several biological properties. In a double-blind study versus placebo, we evaluated the effects of ceruletide on self-rated hunger and food intake at lunch time, as well as on body weight in 14 obese women hospitalized for weight reduction and on a restricted diet. During two 6-day courses of treatment with ceruletide or placebo, ceruletide 0.3 microgram/kg b.wt. or an equivalent volume of its diluent were injected IM at 11.30 a.m., i.e., 30 min before lunch. Feelings of hunger were quantitated, using a visual analogue self-rating scale, prior to the injection of ceruletide or placebo and 30 min thereafter, i.e., just prior to the start of meal ingestion, as well as 2 hr after the start of the meal. Duration and caloric content of food ingested at lunch, as well as morning body weight, were recorded daily. Ceruletide, compared to placebo, did not significantly influence any of the above variables. However, in the first three experimental days, the increase in self-rated hunger from values before the injection to 30 min thereafter was less marked, though not significantly so (0.05 less than p less than 0.1), with ceruletide than with placebo. Thus, it appears that ceruletide, under the experimental conditions of the present study, was not effective in enhancing the patients' motivation to lose weight and to further restrict their food intake at lunch time.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Ineffectiveness of ceruletide to reduce food intake and body weight in obese women hospitalized for weight reduction and treated with a restricted diet. A double-blind study. 330 1

Evidence suggests that the satiety responses to peripherally administered CCK are mediated by a CNS component(s). Since CCK concentrations in the hypothalamus can change with degree of hunger, they may also be involved in the feeding response to peripherally administered CCK. Six-hr fasted rats were administered saline or 2 micrograms/kg CCK-8 and half were allowed to eat a meal. They were sacrificed after a meal or after the fast and hypothalamic content of CCK was measured by RIA. In rats injected with CCK, compared with those injected with saline, CCK concentrations were decreased in the ventromedial hypothalamus (VMH, 39 vs. 47 pg/mg tissue, p less than 0.004) and dorsomedial hypothalamus (17 vs. 21 pg/mg, p less than 0.009) and increased in the lateral hypothalamus (28 vs. 19 pg/mg, p less than 0.01). CCK concentrations in fed compared with fasted rats were higher in the VMH (47 vs. 39 pg/mg, p less than 0.002) and in obese compared with lean rats CCK concentrations were higher in the paraventricular nucleus (48 vs. 38 pg/mg, p less than 0.05), suprachiasmatic nucleus (46 vs. 34 pg/mg, p less than 0.008) and VMH (52 vs. 34 pg/mg, p less than 0.001). Since peripheral injections of CCK influenced concentrations of CCK in hypothalamic areas associated with feeding, these results provide evidence that the feeding response to peripherally injected CCK may be mediated by changes in CCK content of specific brain areas.
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PMID:Changes in brain CCK concentrations with peripheral CCK injections in Zucker rats. 370 77

There is increasing evidence that peptides in the brain are important in the control of food intake. Administration of opioid and CCK peptides have elicited hunger and satiety, respectively. To evaluate the interaction of these peptides and their role in the central nervous system, concentrations of met-enkephalin were measured in the hypothalamus of rats following peripheral administration of CCK; in addition, effects of feeding and fasting and obesity were studied. In CCK- vs. saline-injected rats met-enkephalin concentrations were decreased in the paraventricular nucleus (PVN), suprachiasmatic nucleus (SC), supraoptic nucleus (SON), dorsomedial hypothalamus (DMH) and ventromedial hypothalamus (VMH). In fed compared with fasted rats met-enkephalin concentrations were higher in the anterior hypothalamus (AH) and lower in the SC; in obese compared with lean rats, concentrations were higher in the AH, PVN, SC, SON, DMH, lateral hypothalamus and VMH. These results show that peripheral injections of CCK can decrease concentrations of met-enkephalin in the brain and suggest a mechanism by which these peptides may interact to influence behavior. In addition, the findings support the hypothesis that the hyperphagia which is typical of obese rats may be due to increased concentrations of met-enkephalin.
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PMID:Changes in brain met-enkephalin concentrations with peripheral CCK injections in Zucker rats. 371 42

Intramuscular ceruletide or placebo was given in a randomized double-blind crossover design to 12 non-obese and 12 obese individuals, 30 min before a palatable lunch meal. No significant effects were found on the amount of food intake or the hunger ratings in any group. Although rapid CCK or ceruletide infusions have been found in some studies to reduce food intake in man and animals, slow infusions have increased food intake. Under the present study conditions, the moderate rate of release of ceruletide from intramuscular depots did not affect the food intake.
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PMID:Intramuscular ceruletide does not affect food intake in obese and non-obese human subjects. 399 53

We compared changes in runway performance by rats for sucrose reward following injections of the synthetic C-terminal octapeptide of cholecystokinin (CCK-8) with those seen after variations in food deprivation and injections of lithium chloride. No effects on running for either 10% or 30% sucrose were found following 0.5 to 4.0 micrograms/kg of CCK-8, though such doses suppressed 30-min sucrose intake up to 53%. Statistically reliable slowing of running for 10% sucrose was observed on two series of tests after 8.0 micrograms/kg of CCK-8. Running for 30% sucrose was not significantly affected by this dose. The general ineffectiveness of CCK-8 for producing decrements in running spread contrasts with significantly reduced performance after either reductions in food deprivation (21 h vs 12 and 3 h) or injections of 75 mg/kg lithium chloride. These results suggest that the mode of action of CCK-8 in reducing food intake is different than that produced by changes in hunger or by non-specific interference with motivation by malaise. The finding that CCK-8 can substantially reduce consumption with no apparent changes in appetitive motivation is consistent with the hypothesis that this substance acts only late in the meal to prematurely trigger satiety.
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PMID:Ineffectiveness of cholecystokinin in impairing runway performance. 609 86


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