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Query: UMLS:C0020505 (hyperphagia)
 6,116 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The growth of gastrointestinal mucosa can be related to ingestion and digestion of diet, with fasting producing mucosal hypoplasia and hyperphagia producing mucosal hyperplasia. Experiments were designed to determine whether induction of polyamine metabolism following ingestion of a meal was related to mucosal growth. Activity of the enzyme ornithine decarboxylase (ODC) in both jejunum and ileum but not in duodenum was dependent on the presence of food in the gut; ODC activity was more than 200-fold greater in mucosa of fed rats than in fasted rats. Inhibition of ODC with difluoromethylornithine lead to mucosal atrophy in ileum but not in duodenum. Refeeding of fasted rats resulted in significant induction of ODC in duodenal, ileal, and colonic, but not fundic, mucosa. In addition, two hormones, epidermal growth factor and glucagon, were effective inducers of ileal ODC activity. Direct evidence for hormonal involvement in the postprandial rise in mucosal ODC activity was provided by experiments in rats that had undergone ileal bypass surgery. After refeeding of fasted rats mucosal ODC activity was induced in both ileum left in continuity and in the bypassed segment. Refeeding of elemental diets demonstrated that ingestion of carbohydrate alone was sufficient for maximal enzyme induction. Mixed amino acids or glyceryl trioleate were no more effective inducers than nonnutritive solutions of cellulose or saccharin. These data demonstrate that hormones which are released during ingestion and digestion of a meal are the stimuli for induction of mucosal polyamine metabolism, suggesting that food-induced mucosal growth is hormonally mediated.
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PMID:Hormonal regulation of postprandial induction of gastrointestinal ornithine decarboxylase activity. 309 78

The aim of this study was to investigate whether the central nervous system regulates mucosal cell growth and apoptosis in the rat small intestine. Ornithine decarboxylase is a key enzyme for polyamine synthesis, which plays an important role in intestinal mucosal growth. The increase in ornithine decarboxylase activity in the duodenum just before a dark period was abolished by truncal vagotomy. An infusion of 2-deoxy-D-glucose into the third cerebroventricle activated the enzyme activity in the small intestine. Epithelial homeostasis is balanced by the regulation of cell proliferation and cell death. Intestinal mucosal apoptosis decreased in rats with ventromedial hypothalamus lesions, which induced hyperphagia and obesity. In contrast, sustained anorexia induced by 1-deoxy-D-glucosamine increased intestinal apoptosis. These results indicate that the central nervous system, in addition to local factors, is related to the regulation of mucosal homeostasis in the intestinal mucosa.
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PMID:Homeostasis in the small intestinal mucosa balanced between cell proliferation and apoptosis is regulated partly by the central nervous system. 1257 82