title: Comparative influences of acoustic and cold stress on gastrointestinal transit in mice.
abstract: The effects of acoustic and cold stress on gastric emptying and intestinal transit were evaluated in mice treated with saline, diazepam, muscimol, propranolol, and naloxone using a radiolabeled chromium test meal. Acoustic stress (AS) was produced by playing music from a magnetic tape through loudspeakers (less than 86 dB) in a confined box at room temperature; and cold stress (CS) was produced by cold (10 degrees C) exposure. AS and CS sessions lasted 20 min. Both AS and CS were accompanied by a significant (P less than 0.05) increase in gastric emptying during at least 1 h. When measured 30 min after the meal, AS and CS increased gastric emptying from 43% of the test meal to 63 and 73%, respectively. Only CS affected intestinal transit, causing a 12.1% increase of the geometric center when measured 30 min after the test meal. Diazepam (0.5 mg/kg) muscimol (0.5 mg/kg), or propranolol (1 mg/kg) administered intraperitoneally reduced or abolished the effects of AS and CS on both gastric emptying and intestinal transit. In contrast naloxone (0.2 mg/kg im), which increased gastric emptying when injected alone, was unable to affect the AS-induced alterations of gastric emptying but partially reduced those of CS. Intracerebroventricular administration of corticotropin-releasing factor (250 ng/kg) also increased by 52.1% the gastric emptying, whereas the geometric center was not affected. It is concluded that both AS and CS accelerate gastric emptying in mice.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D003080:Cold Temperature; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology; D004064:Digestive System / Q000378:metabolism*; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D013016:Sound; D013268:Stimulation, Chemical; D013312:Stress, Physiological / Q000378:metabolism*
chemical_list: D003346:Corticotropin-Releasing Hormone