Evidence for the involvement of corticotropin-releasing factor in the gastrointestinal disturbances induced by acoustic and cold stress in mice.

The influence of acoustic (AS) and cold (CS) stress on gastric emptying and intestinal transit were evaluated in mice using a radiolabelled 51chromium test meal. AS was produced by playing music through loudspeakers (less than 86 dB) in a confined box at room temperature (20 degrees C) and CS was obtained by exposure to 10 degrees C. Twenty minutes exposure to AS or CS caused a significant (P less than 0.05) increase in gastric emptying in mice. Intracerebroventricular (i.c.v.) administration of 150 ng of rat corticotropin-releasing factor (rCRF), 30 min before the test meal, also increased gastric emptying but neither intraperitoneal (i.p.) administration of rCRF at the same dosage nor corticosterone (300 ng) and ACTH (375 microU) were able to induce significant changes in gastric emptying. The increase in gastric emptying induced by AS and CS and by i.c.v. injection of rCRF were blocked by previous i.p. administration of an antiserum against rCRF. These findings strongly support the hypothesis that alterations in gastric emptying induced by AS and CS in mice are due to the release of CRF acting directly on central structures involved in the control of gastrointestinal motility.