Effects of limited access to a fat option on food intake and body composition in female rats

Abstract

Objective The present investigation sought to determine if limiting access to an optional fatty food would induce binge‐type behavior patterns in non–energy‐deprived female rats. Method Four groups of rats had continuous access to a commercial rodent diet throughout the 8‐week study. In addition: (1) the control group had no access to vegetable shortening; (2) the high limitation group had access to shortening for 2 hr for 3 days each week; (3) the low limitation group had access to shortening for 2 hr every day; and (4) the no limitation group had continuous access to shortening. Results As access to the shortening decreased, intake during the 2‐hr access period increased. Total energy intake and body weight did not differ among groups. Body fat was greatest in the rats that ate the most cumulative shortening. Discussion These results indicate that, even under non–energy‐deprived conditions, limiting access to a preferred fatty food can induce binge‐type behavior in female rats. © 2000 by John Wiley & Sons, Inc. Int J Eat Disord 28: 436–445, 2000.

Baclofen, raclopride, and naltrexone differentially reduce solid fat emulsion intake under limited access conditions

“…The large intakes of the 18% and 32% fat emulsions may have been close to the maximum capacity of the rats, thus eliminating the possibility of differential daily and intermittent intakes. This is in contrast to prior studies using a similar rat model of binge-type eating in which rats on an intermittent schedule of access consumed significantly more solid 100% vegetable shortening ("binge") during their brief access period than did rats given daily brief access to the shortening (Corwin, 2004;Corwin et al, 1998;Davis, et al, 2007;Dimitriou et al, 2000;Thomas et al, 2002). The large intakes of the Intermittent groups in the present study would typically be perceived as binge-type eating if not for the concurrently elevated intake in the Daily groups.…”

“…Rats on the Intermittent schedule of access were provided 1-hr of availability to their assigned solid fat emulsion on Mondays, Wednesdays, and Fridays only (I-18%, I-32%, and I-56%, N=10 each). These schedules were chosen based upon studies in which intermittent access induced binge-type consumption of 100% solid vegetable shortening (Corwin, 2004;Corwin, et al, 1998;Dimitriou, et al, 2000;Thomas, et al, 2002;Wojnicki et al, 2006). Rats were then placed on their assigned access schedules for a period of five weeks to establish a baseline before drug dose-effect curves were determined.…”

“…Rats were then placed on their assigned access schedules for a period of five weeks to establish a baseline before drug dose-effect curves were determined. Previous research has shown bingetype behavior to develop and become stable within this time frame (Corwin, 2004;Corwin et al, 1998;Dimitriou, et al, 2000;Thomas, et al, 2002). Chow consumption was monitored in addition to the grams of emulsion consumed during the 1-hr period of availability.…”

“…A behavioral model of binge-type eating in rats has been developed over the past few years in which an Intermittent (Monday, Wednesday, Friday or every third day) schedule of access to 100% vegetable shortening provided during a brief (1-2 hr) period of availability promotes excessive intakes relative to a Daily schedule of access (Corwin, 2004;Corwin and BudaLevin, 2004;Corwin et al, 1998;Davis, et al, 2007;Dimitriou, et al 2000;Thomas, et al, 2002). It has also been shown that under an Intermittent schedule of access rats consume as much shortening during the brief period of availability as is consumed in a 24-hr period when rats have continuous shortening access (24-hr per day -7 days/week) (Dimitriou et al, 2000).…”

“…It has also been shown that under an Intermittent schedule of access rats consume as much shortening during the brief period of availability as is consumed in a 24-hr period when rats have continuous shortening access (24-hr per day -7 days/week) (Dimitriou et al, 2000).…”