Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020505 (hyperphagia)
 6,116 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The concentrations and synthesis of monoamines in various hypothalamic nuclei and the influence of monoaminergic drugs on food intake were studied in two rat lines produced by selective outbreeding for voluntary high and low alcohol drinking. The hypothalamic nuclei of the alcohol-preferring AA rats contained slightly more serotonin than those of the alcohol-avoiding ANA rats, but the accumulation of 5-hydroxytryptophan after inhibition of aromatic amino acid decarboxylase was the same in both lines. There was no significant difference in the basal concentrations of catecholamines between the lines, but the accumulation of L-DOPA was significantly greater in the ANA than the AA rats, suggesting differences in catecholamine turnover. This difference was significant in the paraventricular nucleus, which is involved in the regulation of food intake. Clonidine (an alpha 2-agonist) and 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT, a 5-HT1A agonist) induced hyperphagia and 1-(3-trifluoromethylphenyl)piperazine (TFMPP, a 5-HT1B agonist) induced hypophagia dose-dependently in both rat lines. Clonidine tended to be more potent in the ANA than the AA rats. Food intake following a 20-h fast was significantly lower in the ANA than AA rats. These results suggest that the alcohol-avoiding ANA and alcohol-preferring AA rats have different hypothalamic monoamine mechanisms controlling food intake, which could also partially account for their differential alcohol acceptance.
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PMID:Hypothalamic monoamines and food intake in alcohol-preferring AA and alcohol-avoiding ANA rats. 182 11

We explored energy and macronutrient intake in patients with Graves' hyperthyroidism. We specifically hypothesized that hyperthyroidism is associated with increased appetite for carbohydrates, because of enhanced sympathetic tone and diminished serotonin mediated neurotransmission in the brain. To test this hypothesis, we measured food intake by dietary history and food selected for lunch in the laboratory in 14 patients with Graves' hyperthyroidism. Twenty-four-hour catecholamine excretion was used as a measure of activity of the sympathetic nervous system (SNS) and the plasma [Trp]/[NAA] ratio was measured to estimate (rate limiting) precursor availability for brain 5-hydroxytryptamine synthesis. All measurements were repeated after the subjects had been treated to establish euthyroidism. In addition, the effects of nonselective beta-adrenoceptor blockade upon these parameters were studied to evaluate the influence of beta-adrenergic hyperactivity on food intake. Hyperthyroidism was marked by increased SNS activity and reduced plasma [Trp]/[NAA] ratio. Accordingly, energy intake was considerably and significantly increased in hyper vs. euthyroidism, which was fully attributable to enhanced carbohydrate consumption, as protein and fat intake were not affected. These results suggest that hyperthyroidism alters the neurophysiology of food intake regulation. Increased SNS activity and reduced Trp precursor availability for 5-hydroxytryptamine synthesis in the brain may drive the marked hyperphagia and craving for carbohydrates that appears to characterize hyperthyroid patients. Because propranolol did not affect food intake in hyperthyroidism, the potential effect of catecholamines on food intake might be mediated by alpha-adrenoceptors.
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PMID:Food choice in hyperthyroidism: potential influence of the autonomic nervous system and brain serotonin precursor availability. 1173 50