Behavioral and neurochemical mechanisms of the action of mild stress in the enhancement of feeding

E O'Hare, David Shaw, KJ Tierney, Eun-Mee Kim, AS Levine, RA Shephard

Research output: Contribution to journalArticle

13 Citations (Scopus)


Rats were trained to respond under a cyclic-ratio schedule of reinforcement composed of an ascending, followed by a descending, sequence of ratio values. Subjects were trained while exposed to 70 dB white noise, then tested while exposed to 70 or 90 dB white noise. Exposure to 90 dB white noise elevated the response function (p < .02). Naloxone was then administered intraperitoneally at 0.3, 1.0, and 3.0 mg/kg under 70 dB and 90 dB white noise. Naloxone administration (1.0 and 3.0 mg/kg) significantly depressed the response function obtained under 90 dB white noise (ps < .01) but did not affect the function obtained under 70 dB white noise. These findings suggest that mild stress increases food intake through a mechanism affecting palatability enhanced by the release of endogenous opioids.
Original languageEnglish
Pages (from-to)173-177
JournalBehavioral Neuroscience
Issue number1
Publication statusPublished - Feb 2004


Cite this