The effects of intermittent dietary supplementation with fish oil on high fat diet‐induced enhanced sensitivity to the behavioral effects of dopaminergic drugs

Eating a high fat diet can lead to obesity, type 2 diabetes, and dopamine system dysfunction. For example, rats eating high fat laboratory chow are more sensitive than rats eating standard chow to the behavioral effects of the dopamine receptor D 2 /D 3 receptor agonist quinpirole. Specifically, quinpirole induces yawning in rats, and quinpirole‐induced yawning is enhanced in rats eating high fat chow as compared to rats eating standard chow. Daily dietary supplementation with 20% (w/w) fish oil prevents this high fat diet‐induced effect; however, for beneficial effects of fish oil in humans, doctors recommend that patients take fish oil only 2–3 times a week. To test the hypothesis that intermittent (e.g., 2/7 days per week) dietary supplementation with fish oil prevents high fat diet‐induced effects (e.g., weight gain and enhanced sensitivity to the behavioral effects of dopaminergic drugs) rats eating standard chow (17% kcal from fat), high fat chow (60% kcal from fat), and rats eating standard or high fat chow with 20% (w/w) intermittent (e.g., 2/7 days per week) dietary fish oil supplementation were tested once weekly with quinpirole (0.0032–0.32 mg/kg, i.p.) using a cumulative dosing procedure. Consistent with previous reports, eating high fat chow enhanced sensitivity of rats to the behavioral effects of quinpirole. That is, the quinpirole‐induced yawning dose‐response curve was shifted significantly to the left for rats eating high fat chow as compared to rats eating standard chow. Intermittent access to fish oil prevented this effect, since quinpirole‐induced yawning was not different among rats eating standard chow and rats eating high fat chow supplemented with fish oil. Future experiments will examine other dopaminergic drugs (e.g., cocaine) and will focus on understanding the mechanism by which fish oil produces these beneficial effects, by examining the specific omega‐3 polyunsaturated fatty acids found in fish oil. Support or Funding Information A portion of this project was supported by R25 GM069621. This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .