Binge-like palatable food intake in rats reduces preproglucagon in the nucleus tractus solitarius

Publication date: Available online 13 February 2020Source: Physiology & BehaviorAuthor(s): Ashmita Mukherjee, Avery Hum, Tyler J. Gustafson, Elizabeth G. Mietlicki-BaaseAbstractBinge eating involves eating larger than normal quantities of food within a discrete period of time. The neurohormonal controls governing binge-like palatable food intake are not well understood. Glucagon-like peptide-1 (GLP-1), a hormone produced peripherally in the intestine and centrally in the nucleus tractus solitarius (NTS), reduces food intake. Given that the NTS plays a critical role in integrating peripheral and central signals relevant for food intake, as well as the role of GLP-1 in motivated feeding, we tested the hypothesis that expression of the GLP-1 precursor preproglucagon (PPG) would be reduced in the NTS of rats with a history of binge-like palatable food intake. Adult male rats received access to fat for 1h shortly before lights off, either every day (Daily, D) or only 3d/week (Intermittent, INT). INT rats ate significantly more fat than did D rats in sessions where all rats had fat access. After ∼8.5 weeks of diet maintenance, we measured plasma GLP-1 as well as NTS PPG and GLP-1 receptor expression. INT rats had significantly lower NTS PPG mRNA expression compared to D rats. However, plasma GLP-1 was significantly increased in the INT group versus D rats. No significant differences were observed in NTS GLP-1 receptor expression. We also measured plasma insulin levels, fasted blo...
Source: Physiology and Behavior - Category: Physiology Source Type: research