Dietary supplementation with fish oil prevents high fat diet induced enhancement of sensitivity to the behavioral effects of quinpirole in rats

Eating a high fat diet can lead to negative health consequences, such as obesity and insulin resistance. Eating a high fat diet also enhances sensitivity of rats to the behavioral effects of drugs acting on dopamine systems, including the dopamine D 2 /D 3 receptor agonist, quinpirole. To test the hypothesis that dietary supplementation with fish oil prevents high fat diet‐induced enhanced sensitivity to the behavioral effects of quinpirole (0.0032–0.32 mg/kg), adolescent male rats ate standard laboratory chow (17% kcal from fat), high fat chow (60% kcal from fat), standard chow supplemented with fish oil or high fat chow supplemented with fish oil. Similar to previous reports, after 5 weeks, rats eating high fat chow were more sensitive (e.g., leftward shift of the quinpirole dose‐response curve) than rats eating standard chow, to yawning induced by quinpirole. Dietary supplementation with 20% (w/w) fish oil prevented this effect. That is, quinpirole dose‐response curves were not different between rats eating high fat chow supplemented with fish oil and standard chow‐fed controls. These results suggest that although a high fat diet causes enhanced drug sensitivity to the behavioral effects of quinpirole, fish oil supplementation can prevent this. Further research is being conducted to understand the mechanisms underlying this effect, and to examine whether fish oil will reverse the effects of eating a high fat diet once they have already developed.