Search Results
Results 601 - 650 of 1293
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Bungo Takashi - - 2002
Octopamine, known to be an important neurotransmitter in invertebrates, has been noted to have several similarities to noradrenaline (NA) in mammals. The present study was done to elucidate whether central injection of octopamine enhances the feeding behavior of chicks and to investigate the interaction of octopamine with both alpha(1)- and ...
Jonaidi H - - 2002
This study examined the effects of intracerebroventricular injections of gamma-aminobutyric acid (GABA) agonists on short-term food intake in meat-type cockerels. In Experiment 1, birds were injected with various doses of muscimol, a GABA(A) agonist. In Experiment 2, the birds received bicuculline, a GABA(A) antagonist, prior to injection of muscimol. In ...
Kelley A E AE Department of Psychiatry, University of Wisconsin-Madison, 6001 Research Park Blvd., Madison, WI 53719, USA. - - 2002
There is a long-standing interest in the role of endogenous opioid peptides in feeding behavior and, in particular, in the modulation of food reward and palatability. Since drugs such as heroin, morphine, alcohol, and cannabinoids, interact with this system, there may be important common neural substrates between food and drug ...
Baptista Trino - - 2002
Previous studies have shown that prolonged administration of antipsychotic drugs induces obesity in female but not in male rats. To explore the mechanisms involved in this sex-dependent effect, we administered the dopamine antagonist sulpiride (20 mg/kg i.p.) or vehicle (0.1 N HCl) to adult male rats during 21 days and ...
Kim Min Seon - - 2002
Intracerebroventricular (ICV) injection of Agouti related protein (AgRP), an endogenous melanocortin 3 and 4 receptor (MC3/4-R) antagonist, produces a prolonged increase in food intake. To clarify the roles of the MC3-R and MC4-R in AgRP-induced hyperphagia, the feeding effect of AgRP (83-132) was compared with that of the selective MC4-R ...
Butera Peter C - - 2002
Proinflammatory cytokines elicit behavioral and physiological responses that include decreased food intake, fever, and a general disinterest in usual activities. Ovarian hormones modulate immune system activity and responsiveness to cytokines in female mammals, suggesting that sex differences in immune function may be influenced by gonadal steroids. In this experiment, female ...
Kirkham Tim C - - 2002
Endocannabinoids are implicated in appetite and body weight regulation. In rodents, anandamide stimulates eating by actions at central CB1 receptors, and hypothalamic endocannabinoids may be under the negative control of leptin. However, changes to brain endocannabinoid levels in direct relation to feeding or changing nutritional status have not been investigated. ...
Agnello Davide - - 2002
High-mobility group protein-1 (HMG-1 also termed HMGB-1), a DNA-binding protein, regulates gene transcription and stabilizes nucleosome formation. HMG-1 was recently implicated as a cytokine, because it is a late-acting mediator of endotoxin lethality that induces the release of pro-inflammatory cytokines from monocytes. Here it is shown that administration of HMG-1 ...
Air Ellen L - - 2002
The pancreatic hormone, insulin, has been hypothesized to be an important regulator of food intake. Consistent with this hypothesis is the finding that exogenous insulin, in doses that do not affect blood glucose, reliably suppresses food intake and body weight. However, previous experiments have utilized a long-term delivery paradigm, in ...
Ebenezer Ivor S - - 2002
The effects of intracerebroventricular administration of devazepide, a CCK(1) receptor antagonist, was investigated on food intake in rats. In the first experiment, rats (n=5) were deprived of food for 17 h and injected intracerebroventricularly with either vehicle or devazepide (1, 10, 25 or 100 ng). Five minutes after vehicle or ...
Del Prete E - - 2002
In the present study, the effects of peripherally administered amylin and of the amylin-related peptide salmon calcitonin (sCT) on food and water intake was tested for the first time in pygmy goats. In the first series of experiments, the effect of amylin on food (0.5, 1.0 and 2.0 microg/kg b.wt.) ...
Jarosz Patricia A - - 2002
The obese Zucker rat (OZR) exhibits a hyperphagic eating pattern similar to the obese binge eater. Dynorphin, an endogenous agonist of the kappa receptor, is associated with regulation offood intake. Lessened sensitivity to opioid antagonists and/or increased central dynorphin levels may contribute to the hyperphagic eating pattern observed in the ...
Simansky Kenny J - - 2002
Systemic administration of the serotonin (5-HT) releaser/reuptake inhibitor, D-fenfluramine decreases consumption of food in mammals. This hypophagic action involves loci at several levels of the neuraxis. Indirect evidence implicates the parabrachial nucleus (PBN) of the pons as one of these regions. Consistent with this hypothesis, unilateral infusion of D-fenfluramine (200, ...
Menani José Vanderlei - - 2002
Central cholinergic mechanisms are suggested to participate in osmoreceptor-induced water intake. Therefore, central injections of the cholinergic agonist carbachol usually produce water intake (i.e., thirst) and are ineffective in inducing the intake of hypertonic saline solutions (i.e., the operational definition of sodium appetite). Recent studies have indicated that bilateral injections ...
Saadoun A - - 2002
The effects of the 5-HT(1A) receptor agonist 8-OH-DPAT on food and water intake in 16-week-old male chickens were investigated. Injection of 25 or 50 microg/kg of 8-OH-DPAT 15 min before refeeding starved animals (starved-refed) produced a decrease in food intake 1 h after the start of refeeding. No effect was ...
Choi SuJean - - 2002
The mechanisms by which fenfluramine suppresses food intake and body weight have been linked to its ability to enhance transmission across serotonin synapses in brain. This drug initially lowers body weight and suppresses food intake, yet after repeated administration food intake soon returns to normal and body weight no longer ...
Koch Kristin A - - 2002
These studies explored the possibility that glucocorticoids promote parental care in ring doves by mediating, at least in part, the pronounced increase in food consumption that parent doves exhibit while provisioning their young. Plasma concentrations of the endogenous glucocorticoid corticosterone were found to be significantly higher in breeding females during ...
Wenger T - - 2002
The hypothalamus plays an important role in the regulation of several visceral processes, including food intake, thermoregulation and control of anterior pituitary secretion. Endogenous cannabinoids and CB(1) cannabinoid receptors have been found in the hypothalamus. In the present review, we would like to clarify the role of the endocannabinoid system ...
Yoshimatsu Hironobu - - 2002
Hypothalamic neuronal histamine has been shown to regulate feeding behavior and energy metabolism as a target of leptin action in the brain. The present study aimed to examine the involvement of L-histidine, a precursor of neuronal histamine, in the regulation of feeding behavior in rats. Intraperitoneal (ip) injection of L-histidine ...
Nicholson J R - - 2002
Orphanin FQ (Nociceptin) has been reported to stimulate food intake in satiated rats and to stimulate corticosterone release. A large body of evidence exists to link central feeding systems with the regulation of corticosterone. In this study, we sought to determine whether or not circulating corticosterone is necessary for the ...
Zheng Huiyuan - - 2002
The caudal brain stem integrates short-term feedback signals from the oral cavity and the food-handling abdominal viscera, as well as long-term homeostatic, cognitive, and emotional signals from the forebrain, to control ingestive behavior. Glutamate, acting on various receptor subtypes, plays a prominent role in this integrative process. Fourth ventricular injection ...
Blevins J Ernie - - 2002
Dimethyl sulfoxide (DMSO) is becoming increasingly popular as a vehicle in studies employing central injections. The aim of the present study was to determine whether the vehicle required for solubilization of substances for central injection [75% DMSO and 25% artificial CSF (aCSF)] would alter the well-characterized stimulatory response to norepinephrine ...
Ohinata Kousaku - - 2002
Albutensin A (Ala-Phe-Lys-Ala-Trp-Ala-Val-Ala-Arg) derived from serum albumin dose-dependently decreased food intake after intracerebroventricular (10-50 nmol/mouse) or peripheral (0.3-1.0 micromol/mouse) administration in fasted conscious ddY mice. Albutensin A delayed gastric emptying and elevated blood glucose levels. Although albutensin A showed low affinity for bombesin receptor, it decreased food intake in bombesin ...
Aja S - - 2001
Peptides from cocaine- and amphetamine-regulated transcript (CART) reduce food intake in rats when injected into the lateral ventricle. Hypothalamic and hindbrain sites important in the control of feeding contain CART-immunoreactive fibers. To further define the site of CART's anorectic action, we compared feeding and other behavioral responses to third or ...
Hayward M D MD The Vollum Institute, Oregon Health & Science University, Portland, OR 97201, - - 2001
Mice are powerful models to investigate the genetic basis of food reward because many spontaneous obesity mutants exist and the murine genome is accessible to selectively targeted manipulations. Experiments in rats have shown that opioid receptor blockade reduces operant responding to food reinforcers. The present study investigated whether DBA/2J mice ...
Manabe Y - - 2001
We have reported that a diazepam binding inhibitor (DBI)-like peptide is released by the aversive quinine stimuli 'Chem. Senses 25 (2000) 739'. To determine the effect of DBI on the fluid intake, we injected a DBI peptide fragment into the fourth ventricle in mice. DBI suppressed the intake of 5% ...
Zhang Min - - 2002
RATIONALE: Endogenous opioids have been implicated in the hedonic evaluation of food and palatability. Opioids may also be involved in alcohol intake, as there is a positive correlation between alcohol drinking and preference for sweets and fats. Our previous studies have shown that mu opioid stimulation of the nucleus accumbens ...
Sunter D - - 2001
Neuropeptide FF (NPFF) is a mammalian peptide that is found in high concentrations in the central nervous system (CNS) and has also been detected in plasma. Various functions have been attributed to this peptide although its main action in the CNS remains unclear. In this study we observed that intracerebroventricular ...
Rodríguez de Fonseca F - - 2001
Oleylethanolamide (OEA) is a natural analogue of the endogenous cannabinoid anandamide. Like anandamide, OEA is produced in cells in a stimulus-dependent manner and is rapidly eliminated by enzymatic hydrolysis, suggesting a function in cellular signalling. However, OEA does not activate cannabinoid receptors and its biological functions are still unknown. Here ...
Zhang R - - 2001
Both corticortropin-releasing factor (CRF) and glucagon-like peptide-1 (GLP-1) inhibit food intake of chicks, but they also produce other behaviors. The present experiments were undertaken to clarify the interaction of CRF and GLP-1 regarding their anorectic actions as well as other behaviors. In Experiment 1, birds were injected intracerebroventricularly (i.c.v.), following ...
Kamerman Peter - - 2002
We have investigated whether there is circadian variation in the effects of nitric oxide synthase inhibitors on body temperature, physical activity and feeding. We used nocturnally active Sprague-Dawley rats, housed at approximately 24 degrees C with a 12:12 h light:dark cycle (lights on 07:00 hours) and provided with food and ...
Tachibana T - - 2001
To clarify the involvement of endogenous glucagon-like peptide-1 (GLP-1) on feeding in chicks, we examined the central effect of GLP-1 antagonist, exendin (5-39) on food intake. Intracerebroventricular co-injection of exendin (5-39) with GLP-1 attenuated the anorexigenic effect of GLP-1 in layer-type chicks. Furthermore, exendin (5-39) enhanced food intake of layer-type ...
Rowland N E - - 2001
RATIONALE: Recent studies in animals have implicated endogenous cannabinoids in the regulation of palatable food intake, but it is not yet clear to what extent pharmacological agents acting on this system may have sustained actions and applicability to different feeding protocols. OBJECTIVES: In the present study, we examine the effects ...
Bungo T - - 2001
It is known that central injection of glucagon-like peptide-1 (GLP-1) suppresses feeding in rats and chicks, but the systems for GLP-1 are still open with special reference to the chick. The present study was done to determine whether a noradrenergic mechanism contributes to the anorexigenic effect of GLP-1 on the ...
Takagi T - - 2001
It has been demonstrated that L-pipecolic acid (L-PA), a major metabolic intermediate of L-Lysine (L-Lys) in the brain, is involved in the functioning of Gamma-aminobutyric acid. In the present work the effect of intracerebroventricular (i.c.v.) administration of L-PA, and its relatives, on food intake and behavior in neonatal chicks was ...
Zhang R - - 2001
Corticotropin-releasing factor (CRF), urocortin and urotensin I share amino acid sequences, and they inhibit food intake in mammals. CRF plays a potent role in decreasing food intake in avian species, but the effects of urocortin and urotensin I have not been investigated. Therefore, the effect of these three peptides on ...
Ando R - - 2001
Neuropeptide Y is one of the most potent neuropeptides known to induce feeding in animals, and has been suggested to be a physiological signal for food intake. It has been also reported that intracerebroventricular injection of neuropeptide Y stimulates feeding behavior of the neonatal chick. There are many neuropeptide Y ...
Sato T - - 2001
Previous studies suggest that the dopaminergic system in the supraoptic nucleus (SON) is involved not only in the water balance control but also in the food intake regulation. Since we reported that an injection of the D2 receptor antagonist, sulpiride, into specific hypothalamic nuclei (e.g. the LHA, or the VMN) ...
Peters C T - - 2001
The hypothesis that peripheral glucagon-like peptide-1 (GLP-1) is a regulator of both food intake and macronutrient selection in rats was tested by administration of its antagonist, exendin 9-39, and its agonist, exendin 4. The effect of exendin 9-39 given intraperitoneally (i.p.) on food intake was measured after carbohydrate, protein or ...
Kim E M - - 2001
Butorphanol (BT), a mixed kappa- and mu-opioid receptor agonist, induces vigorous food intake in rats. Peripheral injection of BT seems to increase food intake more effectively than intracerebroventricular administration. To further elucidate the nature of BT's influence on consummatory behavior, we examined which feeding-related brain areas exhibit increased c-Fos immunoreactivity ...
Sashihara K - - 2001
1. Fatty acid oxidation is known to be involved in the control of food intake in mammals. The effect of fatty acid oxidation on food intake in chickens was studied using a ketone body (beta-hydroxybutyrate (beta-HB)) and mercaptoacetate (MA) (an inhibitor of fatty acid oxidation). 2. Central and peripheral injection ...
Attoub S - - 2001
We investigated the peripheral effects of an H3-receptor agonist and an H3-receptor antagonist (R)alpha-methylhistamine (Ralpha-MeHA) and thioperamide, respectively, on basal feeding and the CCK8-induced inhibition of food intake in rat. Intraperitoneal injection of thioperamide reduced food intake in a dose-dependent manner with maximal inhibition (35%, P<0.01 vs saline) at 3 ...
Olszewski P K - - 2001
The aim of our experiments was to study the presumed functional relationship between the melanocortin and opioid systems in the regulation of food intake. We determined that a non-selective opioid receptor antagonist, naltrexone, at relatively low doses, decreases food intake induced by i.c.v. agouti-related protein (Agrp). We also observed that ...
Tachibana T - - 2001
It is well known that alpha-melanocyte stimulating hormone (alpha-MSH) inhibits feeding via melanocortin receptor-4 (MC4R) in the mammalian brain. The anorexigenic effect of alpha-MSH is attenuated by agouti-related protein (AGRP), an antagonist for MC4R. Present studies were carried out to clarify whether human AGRP (86-132) antagonizes the anorexigenic effect of ...
Bernier N J - - 2001
Although environmental, social and physical stressors have been shown to inhibit food intake and feeding behavior in fish, little is known about the mechanisms that mediate the appetite-suppressing effects of stress. Since the hypothalamic-pituitary-interrenal (HPI) axis is activated in response to most forms of stress in fish, components of this ...
Choi Y H - - 2001
Glucagon-like peptide-1 (GLP-1) release in response to food ingestion has been associated with decreased food intake. In the present study, we tested the hypothesis that the feeding response to GLP-1 injection into the hypothalamic paraventricular nucleus (PVN) is influenced by the macronutrient composition of the food consumed. In the first ...
Lawrence C B - - 2001
The cytokine interleukin-1 (IL-1), which mediates many responses to infection and injury, induces anorexia and fever through direct actions in the central nervous system. The melanocortin neuropeptides, such as alpha melanocyte-stimulating hormone (alpha-MSH), reportedly antagonize many actions of IL-1, including fever and anorexia. However, it is unknown whether endogenous melanocortins ...
Koegler F H - - 2001
In rodents, stimulation of melanocortin-3 and -4 receptor subtypes (MC3-R and MC4-R) causes a reduction in food intake, whereas antagonism of MC3-R and MC4-R increases food intake. This report describes the effects of the stable alphaMSH analog, NDP-MSH ([Nle(4), D-Phe(7)]alphaMSH), and the endogenous alphaMSH receptor antagonist, agouti-related protein, on feeding ...
Lu X Y - - 2001
Agouti-related protein (AGRP) is a newly identified orexigenic peptide that acts as an endogenous antagonist of melanocortin receptors MC3 and MC4. The present study examined the time course of the orexigenic effects of synthetic AGRP (86-132). Intracerebroventricular infusion of 0.1 nmol AGRP (86-132) increased food intake by 450 +/- 81% ...
Wellman P J - - 2001
This unit describes a method for measuring the consumption of a pellet diet during a 30-min testing session conducted during the late portion of the day. The procedure generates reliable and stable baseline measures of feeding, and is appropriate for assessing experimental manipulations that either enhance (e.g., injecting a peptide ...
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