Sugar withdrawal induced by fasting in rats

• Published in: Appetite Vol. 49; no. 1; p. 275
• Main Authors: Avena, N.M., Bocarsly, M., Rada, P., Kim, A., Hoebel, B.G.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2007
• ISSN: 0195-6663; 1095-8304
• DOI: 10.1016/j.appet.2007.03.022

Bingeing on sugar results in signs of opiate-like dependence, as indicated by naloxone-induced withdrawal. The present experiment tested whether signs of withdrawal would emerge just by fasting, without naloxone. To induce bingeing, rats were maintained on 12-h deprivation followed by 12-h access to a 10% sucrose solution and chow for 28 days. Withdrawal was instigated by 36 h of fasting. These animals displayed anxiety in an elevated plus-maze, compared with an ad libitum chow group that was similarly deprived as a control. In vivo microdialysis showed a concomitant increase in extracellular acetylcholine and decrease in dopamine release in the nucleus accumbens shell. Hypoglycemia did not account for these results. The signs of anxiety and alterations in accumbens dopamine and acetylcholine balance were similar to those described previously for withdrawal from opiates. This supports the concept of “natural addiction” to sugar. In the present case it was observed in rats given an intermittent, binge-eating schedule followed by fasting. This may be a factor in eating disorders that involve bingeing and fasting. Supported by USPHS Grant MH-65024.