天美传媒

Abstract

Binge eating is a core symptom in bulimia nervosa and binge eating disorder. Bingeing episodes are frequently triggered by stress or negative mood and involve intake of highly palatable food. We developed a model of binge eating based on individual sensitivity of female rats to increase sucrose consumption in response to stress. The rats were subjected to unpredictable intermittent 1-h access to 10% sucrose. After stabilization of sucrose intake, the rats were assessed for consistency of higher (for binge-like eating prone, BEP) or lower (for binge-like eating resistant, BER) sucrose intake in response to unpredictable episodes of stress. The BEP rats consumed a larger (20%>BER) amount of sucrose in a discrete (1-h) period of time compared to the BER phenotype in non-stressful conditions and significantly increased sucrose intake (50%>BER) under stress. Analyses of the sucrose licking microstructure revealed that BEP rats had a high motivational drive to consume sucrose in non-stressful condition and an increased hedonic value of sucrose when they were exposed to stressful conditions. BEP rats consumed sucrose much more rapidly under stressful conditions compared to BER rats. In the brain, BEP rats demonstrated strong activation of expression of or exigenic neuropeptide relaxin-3 and its specific receptor RXFP3. Central administration of RXFP3 anagonist prevented stress-induced bingeing on sucrose in BEP rats. . These results highlight the potential role of relaxin-3/RXFP3 system as a novel pharmacological target for the treatment of stress-induced binge eating.

Biography

Email: Elena.Timofeeva@fmed.ulaval.ca